1647 строки
48 KiB
C
1647 строки
48 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright 2016 Broadcom
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*/
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/*
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* Broadcom PDC Mailbox Driver
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* The PDC provides a ring based programming interface to one or more hardware
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* offload engines. For example, the PDC driver works with both SPU-M and SPU2
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* cryptographic offload hardware. In some chips the PDC is referred to as MDE,
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* and in others the FA2/FA+ hardware is used with this PDC driver.
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*
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* The PDC driver registers with the Linux mailbox framework as a mailbox
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* controller, once for each PDC instance. Ring 0 for each PDC is registered as
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* a mailbox channel. The PDC driver uses interrupts to determine when data
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* transfers to and from an offload engine are complete. The PDC driver uses
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* threaded IRQs so that response messages are handled outside of interrupt
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* context.
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*
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* The PDC driver allows multiple messages to be pending in the descriptor
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* rings. The tx_msg_start descriptor index indicates where the last message
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* starts. The txin_numd value at this index indicates how many descriptor
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* indexes make up the message. Similar state is kept on the receive side. When
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* an rx interrupt indicates a response is ready, the PDC driver processes numd
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* descriptors from the tx and rx ring, thus processing one response at a time.
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*/
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#include <linux/errno.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/slab.h>
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#include <linux/debugfs.h>
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#include <linux/interrupt.h>
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#include <linux/wait.h>
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#include <linux/platform_device.h>
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#include <linux/io.h>
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#include <linux/of.h>
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#include <linux/of_device.h>
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#include <linux/of_address.h>
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#include <linux/of_irq.h>
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#include <linux/mailbox_controller.h>
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#include <linux/mailbox/brcm-message.h>
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#include <linux/scatterlist.h>
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#include <linux/dma-direction.h>
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#include <linux/dma-mapping.h>
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#include <linux/dmapool.h>
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#define PDC_SUCCESS 0
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#define RING_ENTRY_SIZE sizeof(struct dma64dd)
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/* # entries in PDC dma ring */
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#define PDC_RING_ENTRIES 512
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/*
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* Minimum number of ring descriptor entries that must be free to tell mailbox
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* framework that it can submit another request
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*/
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#define PDC_RING_SPACE_MIN 15
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#define PDC_RING_SIZE (PDC_RING_ENTRIES * RING_ENTRY_SIZE)
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/* Rings are 8k aligned */
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#define RING_ALIGN_ORDER 13
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#define RING_ALIGN BIT(RING_ALIGN_ORDER)
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#define RX_BUF_ALIGN_ORDER 5
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#define RX_BUF_ALIGN BIT(RX_BUF_ALIGN_ORDER)
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/* descriptor bumping macros */
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#define XXD(x, max_mask) ((x) & (max_mask))
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#define TXD(x, max_mask) XXD((x), (max_mask))
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#define RXD(x, max_mask) XXD((x), (max_mask))
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#define NEXTTXD(i, max_mask) TXD((i) + 1, (max_mask))
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#define PREVTXD(i, max_mask) TXD((i) - 1, (max_mask))
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#define NEXTRXD(i, max_mask) RXD((i) + 1, (max_mask))
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#define PREVRXD(i, max_mask) RXD((i) - 1, (max_mask))
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#define NTXDACTIVE(h, t, max_mask) TXD((t) - (h), (max_mask))
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#define NRXDACTIVE(h, t, max_mask) RXD((t) - (h), (max_mask))
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/* Length of BCM header at start of SPU msg, in bytes */
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#define BCM_HDR_LEN 8
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/*
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* PDC driver reserves ringset 0 on each SPU for its own use. The driver does
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* not currently support use of multiple ringsets on a single PDC engine.
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*/
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#define PDC_RINGSET 0
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/*
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* Interrupt mask and status definitions. Enable interrupts for tx and rx on
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* ring 0
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*/
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#define PDC_RCVINT_0 (16 + PDC_RINGSET)
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#define PDC_RCVINTEN_0 BIT(PDC_RCVINT_0)
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#define PDC_INTMASK (PDC_RCVINTEN_0)
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#define PDC_LAZY_FRAMECOUNT 1
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#define PDC_LAZY_TIMEOUT 10000
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#define PDC_LAZY_INT (PDC_LAZY_TIMEOUT | (PDC_LAZY_FRAMECOUNT << 24))
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#define PDC_INTMASK_OFFSET 0x24
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#define PDC_INTSTATUS_OFFSET 0x20
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#define PDC_RCVLAZY0_OFFSET (0x30 + 4 * PDC_RINGSET)
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#define FA_RCVLAZY0_OFFSET 0x100
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/*
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* For SPU2, configure MDE_CKSUM_CONTROL to write 17 bytes of metadata
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* before frame
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*/
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#define PDC_SPU2_RESP_HDR_LEN 17
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#define PDC_CKSUM_CTRL BIT(27)
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#define PDC_CKSUM_CTRL_OFFSET 0x400
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#define PDC_SPUM_RESP_HDR_LEN 32
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/*
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* Sets the following bits for write to transmit control reg:
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* 11 - PtyChkDisable - parity check is disabled
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* 20:18 - BurstLen = 3 -> 2^7 = 128 byte data reads from memory
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*/
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#define PDC_TX_CTL 0x000C0800
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/* Bit in tx control reg to enable tx channel */
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#define PDC_TX_ENABLE 0x1
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/*
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* Sets the following bits for write to receive control reg:
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* 7:1 - RcvOffset - size in bytes of status region at start of rx frame buf
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* 9 - SepRxHdrDescEn - place start of new frames only in descriptors
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* that have StartOfFrame set
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* 10 - OflowContinue - on rx FIFO overflow, clear rx fifo, discard all
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* remaining bytes in current frame, report error
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* in rx frame status for current frame
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* 11 - PtyChkDisable - parity check is disabled
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* 20:18 - BurstLen = 3 -> 2^7 = 128 byte data reads from memory
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*/
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#define PDC_RX_CTL 0x000C0E00
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/* Bit in rx control reg to enable rx channel */
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#define PDC_RX_ENABLE 0x1
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#define CRYPTO_D64_RS0_CD_MASK ((PDC_RING_ENTRIES * RING_ENTRY_SIZE) - 1)
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/* descriptor flags */
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#define D64_CTRL1_EOT BIT(28) /* end of descriptor table */
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#define D64_CTRL1_IOC BIT(29) /* interrupt on complete */
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#define D64_CTRL1_EOF BIT(30) /* end of frame */
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#define D64_CTRL1_SOF BIT(31) /* start of frame */
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#define RX_STATUS_OVERFLOW 0x00800000
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#define RX_STATUS_LEN 0x0000FFFF
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#define PDC_TXREGS_OFFSET 0x200
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#define PDC_RXREGS_OFFSET 0x220
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/* Maximum size buffer the DMA engine can handle */
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#define PDC_DMA_BUF_MAX 16384
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enum pdc_hw {
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FA_HW, /* FA2/FA+ hardware (i.e. Northstar Plus) */
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PDC_HW /* PDC/MDE hardware (i.e. Northstar 2, Pegasus) */
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};
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struct pdc_dma_map {
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void *ctx; /* opaque context associated with frame */
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};
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/* dma descriptor */
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struct dma64dd {
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u32 ctrl1; /* misc control bits */
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u32 ctrl2; /* buffer count and address extension */
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u32 addrlow; /* memory address of the date buffer, bits 31:0 */
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u32 addrhigh; /* memory address of the date buffer, bits 63:32 */
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};
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/* dma registers per channel(xmt or rcv) */
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struct dma64_regs {
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u32 control; /* enable, et al */
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u32 ptr; /* last descriptor posted to chip */
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u32 addrlow; /* descriptor ring base address low 32-bits */
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u32 addrhigh; /* descriptor ring base address bits 63:32 */
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u32 status0; /* last rx descriptor written by hw */
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u32 status1; /* driver does not use */
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};
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/* cpp contortions to concatenate w/arg prescan */
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#ifndef PAD
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#define _PADLINE(line) pad ## line
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#define _XSTR(line) _PADLINE(line)
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#define PAD _XSTR(__LINE__)
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#endif /* PAD */
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/* dma registers. matches hw layout. */
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struct dma64 {
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struct dma64_regs dmaxmt; /* dma tx */
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u32 PAD[2];
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struct dma64_regs dmarcv; /* dma rx */
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u32 PAD[2];
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};
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/* PDC registers */
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struct pdc_regs {
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u32 devcontrol; /* 0x000 */
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u32 devstatus; /* 0x004 */
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u32 PAD;
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u32 biststatus; /* 0x00c */
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u32 PAD[4];
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u32 intstatus; /* 0x020 */
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u32 intmask; /* 0x024 */
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u32 gptimer; /* 0x028 */
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u32 PAD;
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u32 intrcvlazy_0; /* 0x030 (Only in PDC, not FA2) */
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u32 intrcvlazy_1; /* 0x034 (Only in PDC, not FA2) */
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u32 intrcvlazy_2; /* 0x038 (Only in PDC, not FA2) */
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u32 intrcvlazy_3; /* 0x03c (Only in PDC, not FA2) */
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u32 PAD[48];
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u32 fa_intrecvlazy; /* 0x100 (Only in FA2, not PDC) */
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u32 flowctlthresh; /* 0x104 */
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u32 wrrthresh; /* 0x108 */
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u32 gmac_idle_cnt_thresh; /* 0x10c */
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u32 PAD[4];
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u32 ifioaccessaddr; /* 0x120 */
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u32 ifioaccessbyte; /* 0x124 */
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u32 ifioaccessdata; /* 0x128 */
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u32 PAD[21];
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u32 phyaccess; /* 0x180 */
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u32 PAD;
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u32 phycontrol; /* 0x188 */
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u32 txqctl; /* 0x18c */
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u32 rxqctl; /* 0x190 */
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u32 gpioselect; /* 0x194 */
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u32 gpio_output_en; /* 0x198 */
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u32 PAD; /* 0x19c */
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u32 txq_rxq_mem_ctl; /* 0x1a0 */
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u32 memory_ecc_status; /* 0x1a4 */
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u32 serdes_ctl; /* 0x1a8 */
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u32 serdes_status0; /* 0x1ac */
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u32 serdes_status1; /* 0x1b0 */
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u32 PAD[11]; /* 0x1b4-1dc */
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u32 clk_ctl_st; /* 0x1e0 */
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u32 hw_war; /* 0x1e4 (Only in PDC, not FA2) */
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u32 pwrctl; /* 0x1e8 */
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u32 PAD[5];
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#define PDC_NUM_DMA_RINGS 4
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struct dma64 dmaregs[PDC_NUM_DMA_RINGS]; /* 0x0200 - 0x2fc */
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/* more registers follow, but we don't use them */
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};
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/* structure for allocating/freeing DMA rings */
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struct pdc_ring_alloc {
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dma_addr_t dmabase; /* DMA address of start of ring */
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void *vbase; /* base kernel virtual address of ring */
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u32 size; /* ring allocation size in bytes */
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};
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/*
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* context associated with a receive descriptor.
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* @rxp_ctx: opaque context associated with frame that starts at each
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* rx ring index.
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* @dst_sg: Scatterlist used to form reply frames beginning at a given ring
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* index. Retained in order to unmap each sg after reply is processed.
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* @rxin_numd: Number of rx descriptors associated with the message that starts
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* at a descriptor index. Not set for every index. For example,
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* if descriptor index i points to a scatterlist with 4 entries,
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* then the next three descriptor indexes don't have a value set.
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* @resp_hdr: Virtual address of buffer used to catch DMA rx status
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* @resp_hdr_daddr: physical address of DMA rx status buffer
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*/
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struct pdc_rx_ctx {
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void *rxp_ctx;
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struct scatterlist *dst_sg;
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u32 rxin_numd;
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void *resp_hdr;
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dma_addr_t resp_hdr_daddr;
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};
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/* PDC state structure */
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struct pdc_state {
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/* Index of the PDC whose state is in this structure instance */
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u8 pdc_idx;
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/* Platform device for this PDC instance */
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struct platform_device *pdev;
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/*
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* Each PDC instance has a mailbox controller. PDC receives request
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* messages through mailboxes, and sends response messages through the
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* mailbox framework.
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*/
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struct mbox_controller mbc;
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unsigned int pdc_irq;
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/* tasklet for deferred processing after DMA rx interrupt */
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struct tasklet_struct rx_tasklet;
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/* Number of bytes of receive status prior to each rx frame */
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u32 rx_status_len;
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/* Whether a BCM header is prepended to each frame */
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bool use_bcm_hdr;
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/* Sum of length of BCM header and rx status header */
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u32 pdc_resp_hdr_len;
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/* The base virtual address of DMA hw registers */
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void __iomem *pdc_reg_vbase;
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/* Pool for allocation of DMA rings */
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struct dma_pool *ring_pool;
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/* Pool for allocation of metadata buffers for response messages */
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struct dma_pool *rx_buf_pool;
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/*
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* The base virtual address of DMA tx/rx descriptor rings. Corresponding
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* DMA address and size of ring allocation.
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*/
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struct pdc_ring_alloc tx_ring_alloc;
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struct pdc_ring_alloc rx_ring_alloc;
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struct pdc_regs *regs; /* start of PDC registers */
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struct dma64_regs *txregs_64; /* dma tx engine registers */
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struct dma64_regs *rxregs_64; /* dma rx engine registers */
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/*
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* Arrays of PDC_RING_ENTRIES descriptors
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* To use multiple ringsets, this needs to be extended
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*/
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struct dma64dd *txd_64; /* tx descriptor ring */
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struct dma64dd *rxd_64; /* rx descriptor ring */
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/* descriptor ring sizes */
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u32 ntxd; /* # tx descriptors */
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u32 nrxd; /* # rx descriptors */
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u32 nrxpost; /* # rx buffers to keep posted */
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u32 ntxpost; /* max number of tx buffers that can be posted */
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/*
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* Index of next tx descriptor to reclaim. That is, the descriptor
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* index of the oldest tx buffer for which the host has yet to process
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* the corresponding response.
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*/
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u32 txin;
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/*
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* Index of the first receive descriptor for the sequence of
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* message fragments currently under construction. Used to build up
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* the rxin_numd count for a message. Updated to rxout when the host
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* starts a new sequence of rx buffers for a new message.
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*/
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u32 tx_msg_start;
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/* Index of next tx descriptor to post. */
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u32 txout;
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/*
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* Number of tx descriptors associated with the message that starts
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* at this tx descriptor index.
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*/
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u32 txin_numd[PDC_RING_ENTRIES];
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/*
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* Index of next rx descriptor to reclaim. This is the index of
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* the next descriptor whose data has yet to be processed by the host.
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*/
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u32 rxin;
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/*
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* Index of the first receive descriptor for the sequence of
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* message fragments currently under construction. Used to build up
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* the rxin_numd count for a message. Updated to rxout when the host
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* starts a new sequence of rx buffers for a new message.
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*/
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u32 rx_msg_start;
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/*
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* Saved value of current hardware rx descriptor index.
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* The last rx buffer written by the hw is the index previous to
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* this one.
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*/
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u32 last_rx_curr;
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/* Index of next rx descriptor to post. */
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u32 rxout;
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struct pdc_rx_ctx rx_ctx[PDC_RING_ENTRIES];
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/*
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* Scatterlists used to form request and reply frames beginning at a
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* given ring index. Retained in order to unmap each sg after reply
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* is processed
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*/
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struct scatterlist *src_sg[PDC_RING_ENTRIES];
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/* counters */
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u32 pdc_requests; /* number of request messages submitted */
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u32 pdc_replies; /* number of reply messages received */
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u32 last_tx_not_done; /* too few tx descriptors to indicate done */
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u32 tx_ring_full; /* unable to accept msg because tx ring full */
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u32 rx_ring_full; /* unable to accept msg because rx ring full */
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u32 txnobuf; /* unable to create tx descriptor */
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u32 rxnobuf; /* unable to create rx descriptor */
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u32 rx_oflow; /* count of rx overflows */
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/* hardware type - FA2 or PDC/MDE */
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enum pdc_hw hw_type;
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};
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/* Global variables */
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struct pdc_globals {
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/* Actual number of SPUs in hardware, as reported by device tree */
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u32 num_spu;
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};
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static struct pdc_globals pdcg;
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/* top level debug FS directory for PDC driver */
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static struct dentry *debugfs_dir;
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static ssize_t pdc_debugfs_read(struct file *filp, char __user *ubuf,
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size_t count, loff_t *offp)
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{
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struct pdc_state *pdcs;
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char *buf;
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ssize_t ret, out_offset, out_count;
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out_count = 512;
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buf = kmalloc(out_count, GFP_KERNEL);
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if (!buf)
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return -ENOMEM;
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pdcs = filp->private_data;
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out_offset = 0;
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"SPU %u stats:\n", pdcs->pdc_idx);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"PDC requests....................%u\n",
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pdcs->pdc_requests);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"PDC responses...................%u\n",
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pdcs->pdc_replies);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"Tx not done.....................%u\n",
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pdcs->last_tx_not_done);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"Tx ring full....................%u\n",
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pdcs->tx_ring_full);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"Rx ring full....................%u\n",
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pdcs->rx_ring_full);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"Tx desc write fail. Ring full...%u\n",
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pdcs->txnobuf);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"Rx desc write fail. Ring full...%u\n",
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pdcs->rxnobuf);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"Receive overflow................%u\n",
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pdcs->rx_oflow);
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out_offset += scnprintf(buf + out_offset, out_count - out_offset,
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"Num frags in rx ring............%u\n",
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NRXDACTIVE(pdcs->rxin, pdcs->last_rx_curr,
|
|
pdcs->nrxpost));
|
|
|
|
if (out_offset > out_count)
|
|
out_offset = out_count;
|
|
|
|
ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
|
|
kfree(buf);
|
|
return ret;
|
|
}
|
|
|
|
static const struct file_operations pdc_debugfs_stats = {
|
|
.owner = THIS_MODULE,
|
|
.open = simple_open,
|
|
.read = pdc_debugfs_read,
|
|
};
|
|
|
|
/**
|
|
* pdc_setup_debugfs() - Create the debug FS directories. If the top-level
|
|
* directory has not yet been created, create it now. Create a stats file in
|
|
* this directory for a SPU.
|
|
* @pdcs: PDC state structure
|
|
*/
|
|
static void pdc_setup_debugfs(struct pdc_state *pdcs)
|
|
{
|
|
char spu_stats_name[16];
|
|
|
|
if (!debugfs_initialized())
|
|
return;
|
|
|
|
snprintf(spu_stats_name, 16, "pdc%d_stats", pdcs->pdc_idx);
|
|
if (!debugfs_dir)
|
|
debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
|
|
|
|
/* S_IRUSR == 0400 */
|
|
debugfs_create_file(spu_stats_name, 0400, debugfs_dir, pdcs,
|
|
&pdc_debugfs_stats);
|
|
}
|
|
|
|
static void pdc_free_debugfs(void)
|
|
{
|
|
debugfs_remove_recursive(debugfs_dir);
|
|
debugfs_dir = NULL;
|
|
}
|
|
|
|
/**
|
|
* pdc_build_rxd() - Build DMA descriptor to receive SPU result.
|
|
* @pdcs: PDC state for SPU that will generate result
|
|
* @dma_addr: DMA address of buffer that descriptor is being built for
|
|
* @buf_len: Length of the receive buffer, in bytes
|
|
* @flags: Flags to be stored in descriptor
|
|
*/
|
|
static inline void
|
|
pdc_build_rxd(struct pdc_state *pdcs, dma_addr_t dma_addr,
|
|
u32 buf_len, u32 flags)
|
|
{
|
|
struct device *dev = &pdcs->pdev->dev;
|
|
struct dma64dd *rxd = &pdcs->rxd_64[pdcs->rxout];
|
|
|
|
dev_dbg(dev,
|
|
"Writing rx descriptor for PDC %u at index %u with length %u. flags %#x\n",
|
|
pdcs->pdc_idx, pdcs->rxout, buf_len, flags);
|
|
|
|
rxd->addrlow = cpu_to_le32(lower_32_bits(dma_addr));
|
|
rxd->addrhigh = cpu_to_le32(upper_32_bits(dma_addr));
|
|
rxd->ctrl1 = cpu_to_le32(flags);
|
|
rxd->ctrl2 = cpu_to_le32(buf_len);
|
|
|
|
/* bump ring index and return */
|
|
pdcs->rxout = NEXTRXD(pdcs->rxout, pdcs->nrxpost);
|
|
}
|
|
|
|
/**
|
|
* pdc_build_txd() - Build a DMA descriptor to transmit a SPU request to
|
|
* hardware.
|
|
* @pdcs: PDC state for the SPU that will process this request
|
|
* @dma_addr: DMA address of packet to be transmitted
|
|
* @buf_len: Length of tx buffer, in bytes
|
|
* @flags: Flags to be stored in descriptor
|
|
*/
|
|
static inline void
|
|
pdc_build_txd(struct pdc_state *pdcs, dma_addr_t dma_addr, u32 buf_len,
|
|
u32 flags)
|
|
{
|
|
struct device *dev = &pdcs->pdev->dev;
|
|
struct dma64dd *txd = &pdcs->txd_64[pdcs->txout];
|
|
|
|
dev_dbg(dev,
|
|
"Writing tx descriptor for PDC %u at index %u with length %u, flags %#x\n",
|
|
pdcs->pdc_idx, pdcs->txout, buf_len, flags);
|
|
|
|
txd->addrlow = cpu_to_le32(lower_32_bits(dma_addr));
|
|
txd->addrhigh = cpu_to_le32(upper_32_bits(dma_addr));
|
|
txd->ctrl1 = cpu_to_le32(flags);
|
|
txd->ctrl2 = cpu_to_le32(buf_len);
|
|
|
|
/* bump ring index and return */
|
|
pdcs->txout = NEXTTXD(pdcs->txout, pdcs->ntxpost);
|
|
}
|
|
|
|
/**
|
|
* pdc_receive_one() - Receive a response message from a given SPU.
|
|
* @pdcs: PDC state for the SPU to receive from
|
|
*
|
|
* When the return code indicates success, the response message is available in
|
|
* the receive buffers provided prior to submission of the request.
|
|
*
|
|
* Return: PDC_SUCCESS if one or more receive descriptors was processed
|
|
* -EAGAIN indicates that no response message is available
|
|
* -EIO an error occurred
|
|
*/
|
|
static int
|
|
pdc_receive_one(struct pdc_state *pdcs)
|
|
{
|
|
struct device *dev = &pdcs->pdev->dev;
|
|
struct mbox_controller *mbc;
|
|
struct mbox_chan *chan;
|
|
struct brcm_message mssg;
|
|
u32 len, rx_status;
|
|
u32 num_frags;
|
|
u8 *resp_hdr; /* virtual addr of start of resp message DMA header */
|
|
u32 frags_rdy; /* number of fragments ready to read */
|
|
u32 rx_idx; /* ring index of start of receive frame */
|
|
dma_addr_t resp_hdr_daddr;
|
|
struct pdc_rx_ctx *rx_ctx;
|
|
|
|
mbc = &pdcs->mbc;
|
|
chan = &mbc->chans[0];
|
|
mssg.type = BRCM_MESSAGE_SPU;
|
|
|
|
/*
|
|
* return if a complete response message is not yet ready.
|
|
* rxin_numd[rxin] is the number of fragments in the next msg
|
|
* to read.
|
|
*/
|
|
frags_rdy = NRXDACTIVE(pdcs->rxin, pdcs->last_rx_curr, pdcs->nrxpost);
|
|
if ((frags_rdy == 0) ||
|
|
(frags_rdy < pdcs->rx_ctx[pdcs->rxin].rxin_numd))
|
|
/* No response ready */
|
|
return -EAGAIN;
|
|
|
|
num_frags = pdcs->txin_numd[pdcs->txin];
|
|
WARN_ON(num_frags == 0);
|
|
|
|
dma_unmap_sg(dev, pdcs->src_sg[pdcs->txin],
|
|
sg_nents(pdcs->src_sg[pdcs->txin]), DMA_TO_DEVICE);
|
|
|
|
pdcs->txin = (pdcs->txin + num_frags) & pdcs->ntxpost;
|
|
|
|
dev_dbg(dev, "PDC %u reclaimed %d tx descriptors",
|
|
pdcs->pdc_idx, num_frags);
|
|
|
|
rx_idx = pdcs->rxin;
|
|
rx_ctx = &pdcs->rx_ctx[rx_idx];
|
|
num_frags = rx_ctx->rxin_numd;
|
|
/* Return opaque context with result */
|
|
mssg.ctx = rx_ctx->rxp_ctx;
|
|
rx_ctx->rxp_ctx = NULL;
|
|
resp_hdr = rx_ctx->resp_hdr;
|
|
resp_hdr_daddr = rx_ctx->resp_hdr_daddr;
|
|
dma_unmap_sg(dev, rx_ctx->dst_sg, sg_nents(rx_ctx->dst_sg),
|
|
DMA_FROM_DEVICE);
|
|
|
|
pdcs->rxin = (pdcs->rxin + num_frags) & pdcs->nrxpost;
|
|
|
|
dev_dbg(dev, "PDC %u reclaimed %d rx descriptors",
|
|
pdcs->pdc_idx, num_frags);
|
|
|
|
dev_dbg(dev,
|
|
"PDC %u txin %u, txout %u, rxin %u, rxout %u, last_rx_curr %u\n",
|
|
pdcs->pdc_idx, pdcs->txin, pdcs->txout, pdcs->rxin,
|
|
pdcs->rxout, pdcs->last_rx_curr);
|
|
|
|
if (pdcs->pdc_resp_hdr_len == PDC_SPUM_RESP_HDR_LEN) {
|
|
/*
|
|
* For SPU-M, get length of response msg and rx overflow status.
|
|
*/
|
|
rx_status = *((u32 *)resp_hdr);
|
|
len = rx_status & RX_STATUS_LEN;
|
|
dev_dbg(dev,
|
|
"SPU response length %u bytes", len);
|
|
if (unlikely(((rx_status & RX_STATUS_OVERFLOW) || (!len)))) {
|
|
if (rx_status & RX_STATUS_OVERFLOW) {
|
|
dev_err_ratelimited(dev,
|
|
"crypto receive overflow");
|
|
pdcs->rx_oflow++;
|
|
} else {
|
|
dev_info_ratelimited(dev, "crypto rx len = 0");
|
|
}
|
|
return -EIO;
|
|
}
|
|
}
|
|
|
|
dma_pool_free(pdcs->rx_buf_pool, resp_hdr, resp_hdr_daddr);
|
|
|
|
mbox_chan_received_data(chan, &mssg);
|
|
|
|
pdcs->pdc_replies++;
|
|
return PDC_SUCCESS;
|
|
}
|
|
|
|
/**
|
|
* pdc_receive() - Process as many responses as are available in the rx ring.
|
|
* @pdcs: PDC state
|
|
*
|
|
* Called within the hard IRQ.
|
|
* Return:
|
|
*/
|
|
static int
|
|
pdc_receive(struct pdc_state *pdcs)
|
|
{
|
|
int rx_status;
|
|
|
|
/* read last_rx_curr from register once */
|
|
pdcs->last_rx_curr =
|
|
(ioread32((const void __iomem *)&pdcs->rxregs_64->status0) &
|
|
CRYPTO_D64_RS0_CD_MASK) / RING_ENTRY_SIZE;
|
|
|
|
do {
|
|
/* Could be many frames ready */
|
|
rx_status = pdc_receive_one(pdcs);
|
|
} while (rx_status == PDC_SUCCESS);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* pdc_tx_list_sg_add() - Add the buffers in a scatterlist to the transmit
|
|
* descriptors for a given SPU. The scatterlist buffers contain the data for a
|
|
* SPU request message.
|
|
* @spu_idx: The index of the SPU to submit the request to, [0, max_spu)
|
|
* @sg: Scatterlist whose buffers contain part of the SPU request
|
|
*
|
|
* If a scatterlist buffer is larger than PDC_DMA_BUF_MAX, multiple descriptors
|
|
* are written for that buffer, each <= PDC_DMA_BUF_MAX byte in length.
|
|
*
|
|
* Return: PDC_SUCCESS if successful
|
|
* < 0 otherwise
|
|
*/
|
|
static int pdc_tx_list_sg_add(struct pdc_state *pdcs, struct scatterlist *sg)
|
|
{
|
|
u32 flags = 0;
|
|
u32 eot;
|
|
u32 tx_avail;
|
|
|
|
/*
|
|
* Num descriptors needed. Conservatively assume we need a descriptor
|
|
* for every entry in sg.
|
|
*/
|
|
u32 num_desc;
|
|
u32 desc_w = 0; /* Number of tx descriptors written */
|
|
u32 bufcnt; /* Number of bytes of buffer pointed to by descriptor */
|
|
dma_addr_t databufptr; /* DMA address to put in descriptor */
|
|
|
|
num_desc = (u32)sg_nents(sg);
|
|
|
|
/* check whether enough tx descriptors are available */
|
|
tx_avail = pdcs->ntxpost - NTXDACTIVE(pdcs->txin, pdcs->txout,
|
|
pdcs->ntxpost);
|
|
if (unlikely(num_desc > tx_avail)) {
|
|
pdcs->txnobuf++;
|
|
return -ENOSPC;
|
|
}
|
|
|
|
/* build tx descriptors */
|
|
if (pdcs->tx_msg_start == pdcs->txout) {
|
|
/* Start of frame */
|
|
pdcs->txin_numd[pdcs->tx_msg_start] = 0;
|
|
pdcs->src_sg[pdcs->txout] = sg;
|
|
flags = D64_CTRL1_SOF;
|
|
}
|
|
|
|
while (sg) {
|
|
if (unlikely(pdcs->txout == (pdcs->ntxd - 1)))
|
|
eot = D64_CTRL1_EOT;
|
|
else
|
|
eot = 0;
|
|
|
|
/*
|
|
* If sg buffer larger than PDC limit, split across
|
|
* multiple descriptors
|
|
*/
|
|
bufcnt = sg_dma_len(sg);
|
|
databufptr = sg_dma_address(sg);
|
|
while (bufcnt > PDC_DMA_BUF_MAX) {
|
|
pdc_build_txd(pdcs, databufptr, PDC_DMA_BUF_MAX,
|
|
flags | eot);
|
|
desc_w++;
|
|
bufcnt -= PDC_DMA_BUF_MAX;
|
|
databufptr += PDC_DMA_BUF_MAX;
|
|
if (unlikely(pdcs->txout == (pdcs->ntxd - 1)))
|
|
eot = D64_CTRL1_EOT;
|
|
else
|
|
eot = 0;
|
|
}
|
|
sg = sg_next(sg);
|
|
if (!sg)
|
|
/* Writing last descriptor for frame */
|
|
flags |= (D64_CTRL1_EOF | D64_CTRL1_IOC);
|
|
pdc_build_txd(pdcs, databufptr, bufcnt, flags | eot);
|
|
desc_w++;
|
|
/* Clear start of frame after first descriptor */
|
|
flags &= ~D64_CTRL1_SOF;
|
|
}
|
|
pdcs->txin_numd[pdcs->tx_msg_start] += desc_w;
|
|
|
|
return PDC_SUCCESS;
|
|
}
|
|
|
|
/**
|
|
* pdc_tx_list_final() - Initiate DMA transfer of last frame written to tx
|
|
* ring.
|
|
* @pdcs: PDC state for SPU to process the request
|
|
*
|
|
* Sets the index of the last descriptor written in both the rx and tx ring.
|
|
*
|
|
* Return: PDC_SUCCESS
|
|
*/
|
|
static int pdc_tx_list_final(struct pdc_state *pdcs)
|
|
{
|
|
/*
|
|
* write barrier to ensure all register writes are complete
|
|
* before chip starts to process new request
|
|
*/
|
|
wmb();
|
|
iowrite32(pdcs->rxout << 4, &pdcs->rxregs_64->ptr);
|
|
iowrite32(pdcs->txout << 4, &pdcs->txregs_64->ptr);
|
|
pdcs->pdc_requests++;
|
|
|
|
return PDC_SUCCESS;
|
|
}
|
|
|
|
/**
|
|
* pdc_rx_list_init() - Start a new receive descriptor list for a given PDC.
|
|
* @pdcs: PDC state for SPU handling request
|
|
* @dst_sg: scatterlist providing rx buffers for response to be returned to
|
|
* mailbox client
|
|
* @ctx: Opaque context for this request
|
|
*
|
|
* Posts a single receive descriptor to hold the metadata that precedes a
|
|
* response. For example, with SPU-M, the metadata is a 32-byte DMA header and
|
|
* an 8-byte BCM header. Moves the msg_start descriptor indexes for both tx and
|
|
* rx to indicate the start of a new message.
|
|
*
|
|
* Return: PDC_SUCCESS if successful
|
|
* < 0 if an error (e.g., rx ring is full)
|
|
*/
|
|
static int pdc_rx_list_init(struct pdc_state *pdcs, struct scatterlist *dst_sg,
|
|
void *ctx)
|
|
{
|
|
u32 flags = 0;
|
|
u32 rx_avail;
|
|
u32 rx_pkt_cnt = 1; /* Adding a single rx buffer */
|
|
dma_addr_t daddr;
|
|
void *vaddr;
|
|
struct pdc_rx_ctx *rx_ctx;
|
|
|
|
rx_avail = pdcs->nrxpost - NRXDACTIVE(pdcs->rxin, pdcs->rxout,
|
|
pdcs->nrxpost);
|
|
if (unlikely(rx_pkt_cnt > rx_avail)) {
|
|
pdcs->rxnobuf++;
|
|
return -ENOSPC;
|
|
}
|
|
|
|
/* allocate a buffer for the dma rx status */
|
|
vaddr = dma_pool_zalloc(pdcs->rx_buf_pool, GFP_ATOMIC, &daddr);
|
|
if (unlikely(!vaddr))
|
|
return -ENOMEM;
|
|
|
|
/*
|
|
* Update msg_start indexes for both tx and rx to indicate the start
|
|
* of a new sequence of descriptor indexes that contain the fragments
|
|
* of the same message.
|
|
*/
|
|
pdcs->rx_msg_start = pdcs->rxout;
|
|
pdcs->tx_msg_start = pdcs->txout;
|
|
|
|
/* This is always the first descriptor in the receive sequence */
|
|
flags = D64_CTRL1_SOF;
|
|
pdcs->rx_ctx[pdcs->rx_msg_start].rxin_numd = 1;
|
|
|
|
if (unlikely(pdcs->rxout == (pdcs->nrxd - 1)))
|
|
flags |= D64_CTRL1_EOT;
|
|
|
|
rx_ctx = &pdcs->rx_ctx[pdcs->rxout];
|
|
rx_ctx->rxp_ctx = ctx;
|
|
rx_ctx->dst_sg = dst_sg;
|
|
rx_ctx->resp_hdr = vaddr;
|
|
rx_ctx->resp_hdr_daddr = daddr;
|
|
pdc_build_rxd(pdcs, daddr, pdcs->pdc_resp_hdr_len, flags);
|
|
return PDC_SUCCESS;
|
|
}
|
|
|
|
/**
|
|
* pdc_rx_list_sg_add() - Add the buffers in a scatterlist to the receive
|
|
* descriptors for a given SPU. The caller must have already DMA mapped the
|
|
* scatterlist.
|
|
* @spu_idx: Indicates which SPU the buffers are for
|
|
* @sg: Scatterlist whose buffers are added to the receive ring
|
|
*
|
|
* If a receive buffer in the scatterlist is larger than PDC_DMA_BUF_MAX,
|
|
* multiple receive descriptors are written, each with a buffer <=
|
|
* PDC_DMA_BUF_MAX.
|
|
*
|
|
* Return: PDC_SUCCESS if successful
|
|
* < 0 otherwise (e.g., receive ring is full)
|
|
*/
|
|
static int pdc_rx_list_sg_add(struct pdc_state *pdcs, struct scatterlist *sg)
|
|
{
|
|
u32 flags = 0;
|
|
u32 rx_avail;
|
|
|
|
/*
|
|
* Num descriptors needed. Conservatively assume we need a descriptor
|
|
* for every entry from our starting point in the scatterlist.
|
|
*/
|
|
u32 num_desc;
|
|
u32 desc_w = 0; /* Number of tx descriptors written */
|
|
u32 bufcnt; /* Number of bytes of buffer pointed to by descriptor */
|
|
dma_addr_t databufptr; /* DMA address to put in descriptor */
|
|
|
|
num_desc = (u32)sg_nents(sg);
|
|
|
|
rx_avail = pdcs->nrxpost - NRXDACTIVE(pdcs->rxin, pdcs->rxout,
|
|
pdcs->nrxpost);
|
|
if (unlikely(num_desc > rx_avail)) {
|
|
pdcs->rxnobuf++;
|
|
return -ENOSPC;
|
|
}
|
|
|
|
while (sg) {
|
|
if (unlikely(pdcs->rxout == (pdcs->nrxd - 1)))
|
|
flags = D64_CTRL1_EOT;
|
|
else
|
|
flags = 0;
|
|
|
|
/*
|
|
* If sg buffer larger than PDC limit, split across
|
|
* multiple descriptors
|
|
*/
|
|
bufcnt = sg_dma_len(sg);
|
|
databufptr = sg_dma_address(sg);
|
|
while (bufcnt > PDC_DMA_BUF_MAX) {
|
|
pdc_build_rxd(pdcs, databufptr, PDC_DMA_BUF_MAX, flags);
|
|
desc_w++;
|
|
bufcnt -= PDC_DMA_BUF_MAX;
|
|
databufptr += PDC_DMA_BUF_MAX;
|
|
if (unlikely(pdcs->rxout == (pdcs->nrxd - 1)))
|
|
flags = D64_CTRL1_EOT;
|
|
else
|
|
flags = 0;
|
|
}
|
|
pdc_build_rxd(pdcs, databufptr, bufcnt, flags);
|
|
desc_w++;
|
|
sg = sg_next(sg);
|
|
}
|
|
pdcs->rx_ctx[pdcs->rx_msg_start].rxin_numd += desc_w;
|
|
|
|
return PDC_SUCCESS;
|
|
}
|
|
|
|
/**
|
|
* pdc_irq_handler() - Interrupt handler called in interrupt context.
|
|
* @irq: Interrupt number that has fired
|
|
* @data: device struct for DMA engine that generated the interrupt
|
|
*
|
|
* We have to clear the device interrupt status flags here. So cache the
|
|
* status for later use in the thread function. Other than that, just return
|
|
* WAKE_THREAD to invoke the thread function.
|
|
*
|
|
* Return: IRQ_WAKE_THREAD if interrupt is ours
|
|
* IRQ_NONE otherwise
|
|
*/
|
|
static irqreturn_t pdc_irq_handler(int irq, void *data)
|
|
{
|
|
struct device *dev = (struct device *)data;
|
|
struct pdc_state *pdcs = dev_get_drvdata(dev);
|
|
u32 intstatus = ioread32(pdcs->pdc_reg_vbase + PDC_INTSTATUS_OFFSET);
|
|
|
|
if (unlikely(intstatus == 0))
|
|
return IRQ_NONE;
|
|
|
|
/* Disable interrupts until soft handler runs */
|
|
iowrite32(0, pdcs->pdc_reg_vbase + PDC_INTMASK_OFFSET);
|
|
|
|
/* Clear interrupt flags in device */
|
|
iowrite32(intstatus, pdcs->pdc_reg_vbase + PDC_INTSTATUS_OFFSET);
|
|
|
|
/* Wakeup IRQ thread */
|
|
tasklet_schedule(&pdcs->rx_tasklet);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/**
|
|
* pdc_tasklet_cb() - Tasklet callback that runs the deferred processing after
|
|
* a DMA receive interrupt. Reenables the receive interrupt.
|
|
* @data: PDC state structure
|
|
*/
|
|
static void pdc_tasklet_cb(struct tasklet_struct *t)
|
|
{
|
|
struct pdc_state *pdcs = from_tasklet(pdcs, t, rx_tasklet);
|
|
|
|
pdc_receive(pdcs);
|
|
|
|
/* reenable interrupts */
|
|
iowrite32(PDC_INTMASK, pdcs->pdc_reg_vbase + PDC_INTMASK_OFFSET);
|
|
}
|
|
|
|
/**
|
|
* pdc_ring_init() - Allocate DMA rings and initialize constant fields of
|
|
* descriptors in one ringset.
|
|
* @pdcs: PDC instance state
|
|
* @ringset: index of ringset being used
|
|
*
|
|
* Return: PDC_SUCCESS if ring initialized
|
|
* < 0 otherwise
|
|
*/
|
|
static int pdc_ring_init(struct pdc_state *pdcs, int ringset)
|
|
{
|
|
int i;
|
|
int err = PDC_SUCCESS;
|
|
struct dma64 *dma_reg;
|
|
struct device *dev = &pdcs->pdev->dev;
|
|
struct pdc_ring_alloc tx;
|
|
struct pdc_ring_alloc rx;
|
|
|
|
/* Allocate tx ring */
|
|
tx.vbase = dma_pool_zalloc(pdcs->ring_pool, GFP_KERNEL, &tx.dmabase);
|
|
if (unlikely(!tx.vbase)) {
|
|
err = -ENOMEM;
|
|
goto done;
|
|
}
|
|
|
|
/* Allocate rx ring */
|
|
rx.vbase = dma_pool_zalloc(pdcs->ring_pool, GFP_KERNEL, &rx.dmabase);
|
|
if (unlikely(!rx.vbase)) {
|
|
err = -ENOMEM;
|
|
goto fail_dealloc;
|
|
}
|
|
|
|
dev_dbg(dev, " - base DMA addr of tx ring %pad", &tx.dmabase);
|
|
dev_dbg(dev, " - base virtual addr of tx ring %p", tx.vbase);
|
|
dev_dbg(dev, " - base DMA addr of rx ring %pad", &rx.dmabase);
|
|
dev_dbg(dev, " - base virtual addr of rx ring %p", rx.vbase);
|
|
|
|
memcpy(&pdcs->tx_ring_alloc, &tx, sizeof(tx));
|
|
memcpy(&pdcs->rx_ring_alloc, &rx, sizeof(rx));
|
|
|
|
pdcs->rxin = 0;
|
|
pdcs->rx_msg_start = 0;
|
|
pdcs->last_rx_curr = 0;
|
|
pdcs->rxout = 0;
|
|
pdcs->txin = 0;
|
|
pdcs->tx_msg_start = 0;
|
|
pdcs->txout = 0;
|
|
|
|
/* Set descriptor array base addresses */
|
|
pdcs->txd_64 = (struct dma64dd *)pdcs->tx_ring_alloc.vbase;
|
|
pdcs->rxd_64 = (struct dma64dd *)pdcs->rx_ring_alloc.vbase;
|
|
|
|
/* Tell device the base DMA address of each ring */
|
|
dma_reg = &pdcs->regs->dmaregs[ringset];
|
|
|
|
/* But first disable DMA and set curptr to 0 for both TX & RX */
|
|
iowrite32(PDC_TX_CTL, &dma_reg->dmaxmt.control);
|
|
iowrite32((PDC_RX_CTL + (pdcs->rx_status_len << 1)),
|
|
&dma_reg->dmarcv.control);
|
|
iowrite32(0, &dma_reg->dmaxmt.ptr);
|
|
iowrite32(0, &dma_reg->dmarcv.ptr);
|
|
|
|
/* Set base DMA addresses */
|
|
iowrite32(lower_32_bits(pdcs->tx_ring_alloc.dmabase),
|
|
&dma_reg->dmaxmt.addrlow);
|
|
iowrite32(upper_32_bits(pdcs->tx_ring_alloc.dmabase),
|
|
&dma_reg->dmaxmt.addrhigh);
|
|
|
|
iowrite32(lower_32_bits(pdcs->rx_ring_alloc.dmabase),
|
|
&dma_reg->dmarcv.addrlow);
|
|
iowrite32(upper_32_bits(pdcs->rx_ring_alloc.dmabase),
|
|
&dma_reg->dmarcv.addrhigh);
|
|
|
|
/* Re-enable DMA */
|
|
iowrite32(PDC_TX_CTL | PDC_TX_ENABLE, &dma_reg->dmaxmt.control);
|
|
iowrite32((PDC_RX_CTL | PDC_RX_ENABLE | (pdcs->rx_status_len << 1)),
|
|
&dma_reg->dmarcv.control);
|
|
|
|
/* Initialize descriptors */
|
|
for (i = 0; i < PDC_RING_ENTRIES; i++) {
|
|
/* Every tx descriptor can be used for start of frame. */
|
|
if (i != pdcs->ntxpost) {
|
|
iowrite32(D64_CTRL1_SOF | D64_CTRL1_EOF,
|
|
&pdcs->txd_64[i].ctrl1);
|
|
} else {
|
|
/* Last descriptor in ringset. Set End of Table. */
|
|
iowrite32(D64_CTRL1_SOF | D64_CTRL1_EOF |
|
|
D64_CTRL1_EOT, &pdcs->txd_64[i].ctrl1);
|
|
}
|
|
|
|
/* Every rx descriptor can be used for start of frame */
|
|
if (i != pdcs->nrxpost) {
|
|
iowrite32(D64_CTRL1_SOF,
|
|
&pdcs->rxd_64[i].ctrl1);
|
|
} else {
|
|
/* Last descriptor in ringset. Set End of Table. */
|
|
iowrite32(D64_CTRL1_SOF | D64_CTRL1_EOT,
|
|
&pdcs->rxd_64[i].ctrl1);
|
|
}
|
|
}
|
|
return PDC_SUCCESS;
|
|
|
|
fail_dealloc:
|
|
dma_pool_free(pdcs->ring_pool, tx.vbase, tx.dmabase);
|
|
done:
|
|
return err;
|
|
}
|
|
|
|
static void pdc_ring_free(struct pdc_state *pdcs)
|
|
{
|
|
if (pdcs->tx_ring_alloc.vbase) {
|
|
dma_pool_free(pdcs->ring_pool, pdcs->tx_ring_alloc.vbase,
|
|
pdcs->tx_ring_alloc.dmabase);
|
|
pdcs->tx_ring_alloc.vbase = NULL;
|
|
}
|
|
|
|
if (pdcs->rx_ring_alloc.vbase) {
|
|
dma_pool_free(pdcs->ring_pool, pdcs->rx_ring_alloc.vbase,
|
|
pdcs->rx_ring_alloc.dmabase);
|
|
pdcs->rx_ring_alloc.vbase = NULL;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* pdc_desc_count() - Count the number of DMA descriptors that will be required
|
|
* for a given scatterlist. Account for the max length of a DMA buffer.
|
|
* @sg: Scatterlist to be DMA'd
|
|
* Return: Number of descriptors required
|
|
*/
|
|
static u32 pdc_desc_count(struct scatterlist *sg)
|
|
{
|
|
u32 cnt = 0;
|
|
|
|
while (sg) {
|
|
cnt += ((sg->length / PDC_DMA_BUF_MAX) + 1);
|
|
sg = sg_next(sg);
|
|
}
|
|
return cnt;
|
|
}
|
|
|
|
/**
|
|
* pdc_rings_full() - Check whether the tx ring has room for tx_cnt descriptors
|
|
* and the rx ring has room for rx_cnt descriptors.
|
|
* @pdcs: PDC state
|
|
* @tx_cnt: The number of descriptors required in the tx ring
|
|
* @rx_cnt: The number of descriptors required i the rx ring
|
|
*
|
|
* Return: true if one of the rings does not have enough space
|
|
* false if sufficient space is available in both rings
|
|
*/
|
|
static bool pdc_rings_full(struct pdc_state *pdcs, int tx_cnt, int rx_cnt)
|
|
{
|
|
u32 rx_avail;
|
|
u32 tx_avail;
|
|
bool full = false;
|
|
|
|
/* Check if the tx and rx rings are likely to have enough space */
|
|
rx_avail = pdcs->nrxpost - NRXDACTIVE(pdcs->rxin, pdcs->rxout,
|
|
pdcs->nrxpost);
|
|
if (unlikely(rx_cnt > rx_avail)) {
|
|
pdcs->rx_ring_full++;
|
|
full = true;
|
|
}
|
|
|
|
if (likely(!full)) {
|
|
tx_avail = pdcs->ntxpost - NTXDACTIVE(pdcs->txin, pdcs->txout,
|
|
pdcs->ntxpost);
|
|
if (unlikely(tx_cnt > tx_avail)) {
|
|
pdcs->tx_ring_full++;
|
|
full = true;
|
|
}
|
|
}
|
|
return full;
|
|
}
|
|
|
|
/**
|
|
* pdc_last_tx_done() - If both the tx and rx rings have at least
|
|
* PDC_RING_SPACE_MIN descriptors available, then indicate that the mailbox
|
|
* framework can submit another message.
|
|
* @chan: mailbox channel to check
|
|
* Return: true if PDC can accept another message on this channel
|
|
*/
|
|
static bool pdc_last_tx_done(struct mbox_chan *chan)
|
|
{
|
|
struct pdc_state *pdcs = chan->con_priv;
|
|
bool ret;
|
|
|
|
if (unlikely(pdc_rings_full(pdcs, PDC_RING_SPACE_MIN,
|
|
PDC_RING_SPACE_MIN))) {
|
|
pdcs->last_tx_not_done++;
|
|
ret = false;
|
|
} else {
|
|
ret = true;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* pdc_send_data() - mailbox send_data function
|
|
* @chan: The mailbox channel on which the data is sent. The channel
|
|
* corresponds to a DMA ringset.
|
|
* @data: The mailbox message to be sent. The message must be a
|
|
* brcm_message structure.
|
|
*
|
|
* This function is registered as the send_data function for the mailbox
|
|
* controller. From the destination scatterlist in the mailbox message, it
|
|
* creates a sequence of receive descriptors in the rx ring. From the source
|
|
* scatterlist, it creates a sequence of transmit descriptors in the tx ring.
|
|
* After creating the descriptors, it writes the rx ptr and tx ptr registers to
|
|
* initiate the DMA transfer.
|
|
*
|
|
* This function does the DMA map and unmap of the src and dst scatterlists in
|
|
* the mailbox message.
|
|
*
|
|
* Return: 0 if successful
|
|
* -ENOTSUPP if the mailbox message is a type this driver does not
|
|
* support
|
|
* < 0 if an error
|
|
*/
|
|
static int pdc_send_data(struct mbox_chan *chan, void *data)
|
|
{
|
|
struct pdc_state *pdcs = chan->con_priv;
|
|
struct device *dev = &pdcs->pdev->dev;
|
|
struct brcm_message *mssg = data;
|
|
int err = PDC_SUCCESS;
|
|
int src_nent;
|
|
int dst_nent;
|
|
int nent;
|
|
u32 tx_desc_req;
|
|
u32 rx_desc_req;
|
|
|
|
if (unlikely(mssg->type != BRCM_MESSAGE_SPU))
|
|
return -ENOTSUPP;
|
|
|
|
src_nent = sg_nents(mssg->spu.src);
|
|
if (likely(src_nent)) {
|
|
nent = dma_map_sg(dev, mssg->spu.src, src_nent, DMA_TO_DEVICE);
|
|
if (unlikely(nent == 0))
|
|
return -EIO;
|
|
}
|
|
|
|
dst_nent = sg_nents(mssg->spu.dst);
|
|
if (likely(dst_nent)) {
|
|
nent = dma_map_sg(dev, mssg->spu.dst, dst_nent,
|
|
DMA_FROM_DEVICE);
|
|
if (unlikely(nent == 0)) {
|
|
dma_unmap_sg(dev, mssg->spu.src, src_nent,
|
|
DMA_TO_DEVICE);
|
|
return -EIO;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Check if the tx and rx rings have enough space. Do this prior to
|
|
* writing any tx or rx descriptors. Need to ensure that we do not write
|
|
* a partial set of descriptors, or write just rx descriptors but
|
|
* corresponding tx descriptors don't fit. Note that we want this check
|
|
* and the entire sequence of descriptor to happen without another
|
|
* thread getting in. The channel spin lock in the mailbox framework
|
|
* ensures this.
|
|
*/
|
|
tx_desc_req = pdc_desc_count(mssg->spu.src);
|
|
rx_desc_req = pdc_desc_count(mssg->spu.dst);
|
|
if (unlikely(pdc_rings_full(pdcs, tx_desc_req, rx_desc_req + 1)))
|
|
return -ENOSPC;
|
|
|
|
/* Create rx descriptors to SPU catch response */
|
|
err = pdc_rx_list_init(pdcs, mssg->spu.dst, mssg->ctx);
|
|
err |= pdc_rx_list_sg_add(pdcs, mssg->spu.dst);
|
|
|
|
/* Create tx descriptors to submit SPU request */
|
|
err |= pdc_tx_list_sg_add(pdcs, mssg->spu.src);
|
|
err |= pdc_tx_list_final(pdcs); /* initiate transfer */
|
|
|
|
if (unlikely(err))
|
|
dev_err(&pdcs->pdev->dev,
|
|
"%s failed with error %d", __func__, err);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int pdc_startup(struct mbox_chan *chan)
|
|
{
|
|
return pdc_ring_init(chan->con_priv, PDC_RINGSET);
|
|
}
|
|
|
|
static void pdc_shutdown(struct mbox_chan *chan)
|
|
{
|
|
struct pdc_state *pdcs = chan->con_priv;
|
|
|
|
if (!pdcs)
|
|
return;
|
|
|
|
dev_dbg(&pdcs->pdev->dev,
|
|
"Shutdown mailbox channel for PDC %u", pdcs->pdc_idx);
|
|
pdc_ring_free(pdcs);
|
|
}
|
|
|
|
/**
|
|
* pdc_hw_init() - Use the given initialization parameters to initialize the
|
|
* state for one of the PDCs.
|
|
* @pdcs: state of the PDC
|
|
*/
|
|
static
|
|
void pdc_hw_init(struct pdc_state *pdcs)
|
|
{
|
|
struct platform_device *pdev;
|
|
struct device *dev;
|
|
struct dma64 *dma_reg;
|
|
int ringset = PDC_RINGSET;
|
|
|
|
pdev = pdcs->pdev;
|
|
dev = &pdev->dev;
|
|
|
|
dev_dbg(dev, "PDC %u initial values:", pdcs->pdc_idx);
|
|
dev_dbg(dev, "state structure: %p",
|
|
pdcs);
|
|
dev_dbg(dev, " - base virtual addr of hw regs %p",
|
|
pdcs->pdc_reg_vbase);
|
|
|
|
/* initialize data structures */
|
|
pdcs->regs = (struct pdc_regs *)pdcs->pdc_reg_vbase;
|
|
pdcs->txregs_64 = (struct dma64_regs *)
|
|
(((u8 *)pdcs->pdc_reg_vbase) +
|
|
PDC_TXREGS_OFFSET + (sizeof(struct dma64) * ringset));
|
|
pdcs->rxregs_64 = (struct dma64_regs *)
|
|
(((u8 *)pdcs->pdc_reg_vbase) +
|
|
PDC_RXREGS_OFFSET + (sizeof(struct dma64) * ringset));
|
|
|
|
pdcs->ntxd = PDC_RING_ENTRIES;
|
|
pdcs->nrxd = PDC_RING_ENTRIES;
|
|
pdcs->ntxpost = PDC_RING_ENTRIES - 1;
|
|
pdcs->nrxpost = PDC_RING_ENTRIES - 1;
|
|
iowrite32(0, &pdcs->regs->intmask);
|
|
|
|
dma_reg = &pdcs->regs->dmaregs[ringset];
|
|
|
|
/* Configure DMA but will enable later in pdc_ring_init() */
|
|
iowrite32(PDC_TX_CTL, &dma_reg->dmaxmt.control);
|
|
|
|
iowrite32(PDC_RX_CTL + (pdcs->rx_status_len << 1),
|
|
&dma_reg->dmarcv.control);
|
|
|
|
/* Reset current index pointers after making sure DMA is disabled */
|
|
iowrite32(0, &dma_reg->dmaxmt.ptr);
|
|
iowrite32(0, &dma_reg->dmarcv.ptr);
|
|
|
|
if (pdcs->pdc_resp_hdr_len == PDC_SPU2_RESP_HDR_LEN)
|
|
iowrite32(PDC_CKSUM_CTRL,
|
|
pdcs->pdc_reg_vbase + PDC_CKSUM_CTRL_OFFSET);
|
|
}
|
|
|
|
/**
|
|
* pdc_hw_disable() - Disable the tx and rx control in the hw.
|
|
* @pdcs: PDC state structure
|
|
*
|
|
*/
|
|
static void pdc_hw_disable(struct pdc_state *pdcs)
|
|
{
|
|
struct dma64 *dma_reg;
|
|
|
|
dma_reg = &pdcs->regs->dmaregs[PDC_RINGSET];
|
|
iowrite32(PDC_TX_CTL, &dma_reg->dmaxmt.control);
|
|
iowrite32(PDC_RX_CTL + (pdcs->rx_status_len << 1),
|
|
&dma_reg->dmarcv.control);
|
|
}
|
|
|
|
/**
|
|
* pdc_rx_buf_pool_create() - Pool of receive buffers used to catch the metadata
|
|
* header returned with each response message.
|
|
* @pdcs: PDC state structure
|
|
*
|
|
* The metadata is not returned to the mailbox client. So the PDC driver
|
|
* manages these buffers.
|
|
*
|
|
* Return: PDC_SUCCESS
|
|
* -ENOMEM if pool creation fails
|
|
*/
|
|
static int pdc_rx_buf_pool_create(struct pdc_state *pdcs)
|
|
{
|
|
struct platform_device *pdev;
|
|
struct device *dev;
|
|
|
|
pdev = pdcs->pdev;
|
|
dev = &pdev->dev;
|
|
|
|
pdcs->pdc_resp_hdr_len = pdcs->rx_status_len;
|
|
if (pdcs->use_bcm_hdr)
|
|
pdcs->pdc_resp_hdr_len += BCM_HDR_LEN;
|
|
|
|
pdcs->rx_buf_pool = dma_pool_create("pdc rx bufs", dev,
|
|
pdcs->pdc_resp_hdr_len,
|
|
RX_BUF_ALIGN, 0);
|
|
if (!pdcs->rx_buf_pool)
|
|
return -ENOMEM;
|
|
|
|
return PDC_SUCCESS;
|
|
}
|
|
|
|
/**
|
|
* pdc_interrupts_init() - Initialize the interrupt configuration for a PDC and
|
|
* specify a threaded IRQ handler for deferred handling of interrupts outside of
|
|
* interrupt context.
|
|
* @pdcs: PDC state
|
|
*
|
|
* Set the interrupt mask for transmit and receive done.
|
|
* Set the lazy interrupt frame count to generate an interrupt for just one pkt.
|
|
*
|
|
* Return: PDC_SUCCESS
|
|
* <0 if threaded irq request fails
|
|
*/
|
|
static int pdc_interrupts_init(struct pdc_state *pdcs)
|
|
{
|
|
struct platform_device *pdev = pdcs->pdev;
|
|
struct device *dev = &pdev->dev;
|
|
struct device_node *dn = pdev->dev.of_node;
|
|
int err;
|
|
|
|
/* interrupt configuration */
|
|
iowrite32(PDC_INTMASK, pdcs->pdc_reg_vbase + PDC_INTMASK_OFFSET);
|
|
|
|
if (pdcs->hw_type == FA_HW)
|
|
iowrite32(PDC_LAZY_INT, pdcs->pdc_reg_vbase +
|
|
FA_RCVLAZY0_OFFSET);
|
|
else
|
|
iowrite32(PDC_LAZY_INT, pdcs->pdc_reg_vbase +
|
|
PDC_RCVLAZY0_OFFSET);
|
|
|
|
/* read irq from device tree */
|
|
pdcs->pdc_irq = irq_of_parse_and_map(dn, 0);
|
|
dev_dbg(dev, "pdc device %s irq %u for pdcs %p",
|
|
dev_name(dev), pdcs->pdc_irq, pdcs);
|
|
|
|
err = devm_request_irq(dev, pdcs->pdc_irq, pdc_irq_handler, 0,
|
|
dev_name(dev), dev);
|
|
if (err) {
|
|
dev_err(dev, "IRQ %u request failed with err %d\n",
|
|
pdcs->pdc_irq, err);
|
|
return err;
|
|
}
|
|
return PDC_SUCCESS;
|
|
}
|
|
|
|
static const struct mbox_chan_ops pdc_mbox_chan_ops = {
|
|
.send_data = pdc_send_data,
|
|
.last_tx_done = pdc_last_tx_done,
|
|
.startup = pdc_startup,
|
|
.shutdown = pdc_shutdown
|
|
};
|
|
|
|
/**
|
|
* pdc_mb_init() - Initialize the mailbox controller.
|
|
* @pdcs: PDC state
|
|
*
|
|
* Each PDC is a mailbox controller. Each ringset is a mailbox channel. Kernel
|
|
* driver only uses one ringset and thus one mb channel. PDC uses the transmit
|
|
* complete interrupt to determine when a mailbox message has successfully been
|
|
* transmitted.
|
|
*
|
|
* Return: 0 on success
|
|
* < 0 if there is an allocation or registration failure
|
|
*/
|
|
static int pdc_mb_init(struct pdc_state *pdcs)
|
|
{
|
|
struct device *dev = &pdcs->pdev->dev;
|
|
struct mbox_controller *mbc;
|
|
int chan_index;
|
|
int err;
|
|
|
|
mbc = &pdcs->mbc;
|
|
mbc->dev = dev;
|
|
mbc->ops = &pdc_mbox_chan_ops;
|
|
mbc->num_chans = 1;
|
|
mbc->chans = devm_kcalloc(dev, mbc->num_chans, sizeof(*mbc->chans),
|
|
GFP_KERNEL);
|
|
if (!mbc->chans)
|
|
return -ENOMEM;
|
|
|
|
mbc->txdone_irq = false;
|
|
mbc->txdone_poll = true;
|
|
mbc->txpoll_period = 1;
|
|
for (chan_index = 0; chan_index < mbc->num_chans; chan_index++)
|
|
mbc->chans[chan_index].con_priv = pdcs;
|
|
|
|
/* Register mailbox controller */
|
|
err = devm_mbox_controller_register(dev, mbc);
|
|
if (err) {
|
|
dev_crit(dev,
|
|
"Failed to register PDC mailbox controller. Error %d.",
|
|
err);
|
|
return err;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* Device tree API */
|
|
static const int pdc_hw = PDC_HW;
|
|
static const int fa_hw = FA_HW;
|
|
|
|
static const struct of_device_id pdc_mbox_of_match[] = {
|
|
{.compatible = "brcm,iproc-pdc-mbox", .data = &pdc_hw},
|
|
{.compatible = "brcm,iproc-fa2-mbox", .data = &fa_hw},
|
|
{ /* sentinel */ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, pdc_mbox_of_match);
|
|
|
|
/**
|
|
* pdc_dt_read() - Read application-specific data from device tree.
|
|
* @pdev: Platform device
|
|
* @pdcs: PDC state
|
|
*
|
|
* Reads the number of bytes of receive status that precede each received frame.
|
|
* Reads whether transmit and received frames should be preceded by an 8-byte
|
|
* BCM header.
|
|
*
|
|
* Return: 0 if successful
|
|
* -ENODEV if device not available
|
|
*/
|
|
static int pdc_dt_read(struct platform_device *pdev, struct pdc_state *pdcs)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct device_node *dn = pdev->dev.of_node;
|
|
const struct of_device_id *match;
|
|
const int *hw_type;
|
|
int err;
|
|
|
|
err = of_property_read_u32(dn, "brcm,rx-status-len",
|
|
&pdcs->rx_status_len);
|
|
if (err < 0)
|
|
dev_err(dev,
|
|
"%s failed to get DMA receive status length from device tree",
|
|
__func__);
|
|
|
|
pdcs->use_bcm_hdr = of_property_read_bool(dn, "brcm,use-bcm-hdr");
|
|
|
|
pdcs->hw_type = PDC_HW;
|
|
|
|
match = of_match_device(of_match_ptr(pdc_mbox_of_match), dev);
|
|
if (match != NULL) {
|
|
hw_type = match->data;
|
|
pdcs->hw_type = *hw_type;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* pdc_probe() - Probe function for PDC driver.
|
|
* @pdev: PDC platform device
|
|
*
|
|
* Reserve and map register regions defined in device tree.
|
|
* Allocate and initialize tx and rx DMA rings.
|
|
* Initialize a mailbox controller for each PDC.
|
|
*
|
|
* Return: 0 if successful
|
|
* < 0 if an error
|
|
*/
|
|
static int pdc_probe(struct platform_device *pdev)
|
|
{
|
|
int err = 0;
|
|
struct device *dev = &pdev->dev;
|
|
struct resource *pdc_regs;
|
|
struct pdc_state *pdcs;
|
|
|
|
/* PDC state for one SPU */
|
|
pdcs = devm_kzalloc(dev, sizeof(*pdcs), GFP_KERNEL);
|
|
if (!pdcs) {
|
|
err = -ENOMEM;
|
|
goto cleanup;
|
|
}
|
|
|
|
pdcs->pdev = pdev;
|
|
platform_set_drvdata(pdev, pdcs);
|
|
pdcs->pdc_idx = pdcg.num_spu;
|
|
pdcg.num_spu++;
|
|
|
|
err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(39));
|
|
if (err) {
|
|
dev_warn(dev, "PDC device cannot perform DMA. Error %d.", err);
|
|
goto cleanup;
|
|
}
|
|
|
|
/* Create DMA pool for tx ring */
|
|
pdcs->ring_pool = dma_pool_create("pdc rings", dev, PDC_RING_SIZE,
|
|
RING_ALIGN, 0);
|
|
if (!pdcs->ring_pool) {
|
|
err = -ENOMEM;
|
|
goto cleanup;
|
|
}
|
|
|
|
err = pdc_dt_read(pdev, pdcs);
|
|
if (err)
|
|
goto cleanup_ring_pool;
|
|
|
|
pdc_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
if (!pdc_regs) {
|
|
err = -ENODEV;
|
|
goto cleanup_ring_pool;
|
|
}
|
|
dev_dbg(dev, "PDC register region res.start = %pa, res.end = %pa",
|
|
&pdc_regs->start, &pdc_regs->end);
|
|
|
|
pdcs->pdc_reg_vbase = devm_ioremap_resource(&pdev->dev, pdc_regs);
|
|
if (IS_ERR(pdcs->pdc_reg_vbase)) {
|
|
err = PTR_ERR(pdcs->pdc_reg_vbase);
|
|
dev_err(&pdev->dev, "Failed to map registers: %d\n", err);
|
|
goto cleanup_ring_pool;
|
|
}
|
|
|
|
/* create rx buffer pool after dt read to know how big buffers are */
|
|
err = pdc_rx_buf_pool_create(pdcs);
|
|
if (err)
|
|
goto cleanup_ring_pool;
|
|
|
|
pdc_hw_init(pdcs);
|
|
|
|
/* Init tasklet for deferred DMA rx processing */
|
|
tasklet_setup(&pdcs->rx_tasklet, pdc_tasklet_cb);
|
|
|
|
err = pdc_interrupts_init(pdcs);
|
|
if (err)
|
|
goto cleanup_buf_pool;
|
|
|
|
/* Initialize mailbox controller */
|
|
err = pdc_mb_init(pdcs);
|
|
if (err)
|
|
goto cleanup_buf_pool;
|
|
|
|
pdc_setup_debugfs(pdcs);
|
|
|
|
dev_dbg(dev, "pdc_probe() successful");
|
|
return PDC_SUCCESS;
|
|
|
|
cleanup_buf_pool:
|
|
tasklet_kill(&pdcs->rx_tasklet);
|
|
dma_pool_destroy(pdcs->rx_buf_pool);
|
|
|
|
cleanup_ring_pool:
|
|
dma_pool_destroy(pdcs->ring_pool);
|
|
|
|
cleanup:
|
|
return err;
|
|
}
|
|
|
|
static int pdc_remove(struct platform_device *pdev)
|
|
{
|
|
struct pdc_state *pdcs = platform_get_drvdata(pdev);
|
|
|
|
pdc_free_debugfs();
|
|
|
|
tasklet_kill(&pdcs->rx_tasklet);
|
|
|
|
pdc_hw_disable(pdcs);
|
|
|
|
dma_pool_destroy(pdcs->rx_buf_pool);
|
|
dma_pool_destroy(pdcs->ring_pool);
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver pdc_mbox_driver = {
|
|
.probe = pdc_probe,
|
|
.remove = pdc_remove,
|
|
.driver = {
|
|
.name = "brcm-iproc-pdc-mbox",
|
|
.of_match_table = of_match_ptr(pdc_mbox_of_match),
|
|
},
|
|
};
|
|
module_platform_driver(pdc_mbox_driver);
|
|
|
|
MODULE_AUTHOR("Rob Rice <rob.rice@broadcom.com>");
|
|
MODULE_DESCRIPTION("Broadcom PDC mailbox driver");
|
|
MODULE_LICENSE("GPL v2");
|