From 5649d37c2b23ad6545709c976b9abbfa8d5f4e11 Mon Sep 17 00:00:00 2001 From: Jayachandran C Date: Mon, 10 Jun 2013 06:30:04 +0000 Subject: [PATCH] MIPS: Netlogic: COP2 save/restore code Add COP2 register state structure and functions for Netlogic XLP. The RX and TX buffers and status registers are to be saved. Since the registers are 64-bit, do the implementation in inline assembly which works on both 32-bit and 64-bit kernels. Signed-off-by: Jayachandran C Cc: linux-mips@linux-mips.org Cc: ddaney.cavm@gmail.com Patchwork: https://patchwork.linux-mips.org/patch/5413/ Signed-off-by: Ralf Baechle --- arch/mips/include/asm/cop2.h | 10 +++ arch/mips/include/asm/processor.h | 13 ++++ arch/mips/netlogic/xlp/Makefile | 2 +- arch/mips/netlogic/xlp/cop2-ex.c | 118 ++++++++++++++++++++++++++++++ 4 files changed, 142 insertions(+), 1 deletion(-) create mode 100644 arch/mips/netlogic/xlp/cop2-ex.c diff --git a/arch/mips/include/asm/cop2.h b/arch/mips/include/asm/cop2.h index b17f38ee1ed4..c1516cc0285f 100644 --- a/arch/mips/include/asm/cop2.h +++ b/arch/mips/include/asm/cop2.h @@ -22,6 +22,16 @@ extern void octeon_cop2_restore(struct octeon_cop2_state *); #define cop2_present 1 #define cop2_lazy_restore 1 +#elif defined(CONFIG_CPU_XLP) + +extern void nlm_cop2_save(struct nlm_cop2_state *); +extern void nlm_cop2_restore(struct nlm_cop2_state *); +#define cop2_save(r) nlm_cop2_save(r) +#define cop2_restore(r) nlm_cop2_restore(r) + +#define cop2_present 1 +#define cop2_lazy_restore 0 + #else #define cop2_present 0 diff --git a/arch/mips/include/asm/processor.h b/arch/mips/include/asm/processor.h index 7c637a461ced..016dc4bffc80 100644 --- a/arch/mips/include/asm/processor.h +++ b/arch/mips/include/asm/processor.h @@ -190,6 +190,16 @@ struct octeon_cvmseg_state { [cpu_dcache_line_size() / sizeof(unsigned long)]; }; +#elif defined(CONFIG_CPU_XLP) +struct nlm_cop2_state { + u64 rx[4]; + u64 tx[4]; + u32 tx_msg_status; + u32 rx_msg_status; +}; + +#define COP2_INIT \ + .cp2 = {{0}, {0}, 0, 0}, #else #define COP2_INIT #endif @@ -236,6 +246,9 @@ struct thread_struct { #ifdef CONFIG_CPU_CAVIUM_OCTEON struct octeon_cop2_state cp2 __attribute__ ((__aligned__(128))); struct octeon_cvmseg_state cvmseg __attribute__ ((__aligned__(128))); +#endif +#ifdef CONFIG_CPU_XLP + struct nlm_cop2_state cp2; #endif struct mips_abi *abi; }; diff --git a/arch/mips/netlogic/xlp/Makefile b/arch/mips/netlogic/xlp/Makefile index a84d6ed3746c..e8dd14c38cb6 100644 --- a/arch/mips/netlogic/xlp/Makefile +++ b/arch/mips/netlogic/xlp/Makefile @@ -1,3 +1,3 @@ -obj-y += setup.o nlm_hal.o +obj-y += setup.o nlm_hal.o cop2-ex.o obj-$(CONFIG_SMP) += wakeup.o obj-$(CONFIG_USB) += usb-init.o diff --git a/arch/mips/netlogic/xlp/cop2-ex.c b/arch/mips/netlogic/xlp/cop2-ex.c new file mode 100644 index 000000000000..52bc5de42005 --- /dev/null +++ b/arch/mips/netlogic/xlp/cop2-ex.c @@ -0,0 +1,118 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2013 Broadcom Corporation. + * + * based on arch/mips/cavium-octeon/cpu.c + * Copyright (C) 2009 Wind River Systems, + * written by Ralf Baechle + */ +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +#include + +/* + * 64 bit ops are done in inline assembly to support 32 bit + * compilation + */ +void nlm_cop2_save(struct nlm_cop2_state *r) +{ + asm volatile( + ".set push\n" + ".set noat\n" + "dmfc2 $1, $0, 0\n" + "sd $1, 0(%1)\n" + "dmfc2 $1, $0, 1\n" + "sd $1, 8(%1)\n" + "dmfc2 $1, $0, 2\n" + "sd $1, 16(%1)\n" + "dmfc2 $1, $0, 3\n" + "sd $1, 24(%1)\n" + "dmfc2 $1, $1, 0\n" + "sd $1, 0(%2)\n" + "dmfc2 $1, $1, 1\n" + "sd $1, 8(%2)\n" + "dmfc2 $1, $1, 2\n" + "sd $1, 16(%2)\n" + "dmfc2 $1, $1, 3\n" + "sd $1, 24(%2)\n" + ".set pop\n" + : "=m"(*r) + : "r"(r->tx), "r"(r->rx)); + + r->tx_msg_status = __read_32bit_c2_register($2, 0); + r->rx_msg_status = __read_32bit_c2_register($3, 0) & 0x0fffffff; +} + +void nlm_cop2_restore(struct nlm_cop2_state *r) +{ + u32 rstat; + + asm volatile( + ".set push\n" + ".set noat\n" + "ld $1, 0(%1)\n" + "dmtc2 $1, $0, 0\n" + "ld $1, 8(%1)\n" + "dmtc2 $1, $0, 1\n" + "ld $1, 16(%1)\n" + "dmtc2 $1, $0, 2\n" + "ld $1, 24(%1)\n" + "dmtc2 $1, $0, 3\n" + "ld $1, 0(%2)\n" + "dmtc2 $1, $1, 0\n" + "ld $1, 8(%2)\n" + "dmtc2 $1, $1, 1\n" + "ld $1, 16(%2)\n" + "dmtc2 $1, $1, 2\n" + "ld $1, 24(%2)\n" + "dmtc2 $1, $1, 3\n" + ".set pop\n" + : : "m"(*r), "r"(r->tx), "r"(r->rx)); + + __write_32bit_c2_register($2, 0, r->tx_msg_status); + rstat = __read_32bit_c2_register($3, 0) & 0xf0000000u; + __write_32bit_c2_register($3, 0, r->rx_msg_status | rstat); +} + +static int nlm_cu2_call(struct notifier_block *nfb, unsigned long action, + void *data) +{ + unsigned long flags; + unsigned int status; + + switch (action) { + case CU2_EXCEPTION: + if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) + break; + local_irq_save(flags); + KSTK_STATUS(current) |= ST0_CU2; + status = read_c0_status(); + write_c0_status(status | ST0_CU2); + nlm_cop2_restore(&(current->thread.cp2)); + write_c0_status(status & ~ST0_CU2); + local_irq_restore(flags); + pr_info("COP2 access enabled for pid %d (%s)\n", + current->pid, current->comm); + return NOTIFY_BAD; /* Don't call default notifier */ + } + + return NOTIFY_OK; /* Let default notifier send signals */ +} + +static int __init nlm_cu2_setup(void) +{ + return cu2_notifier(nlm_cu2_call, 0); +} +early_initcall(nlm_cu2_setup);