MIPS: Octeon: Improve USB reset code for OCTEON II.

At boot time, do a better job of resetting the USB host controller
to make the frequency "eye" diagram more compliant with the USB
standard while making the controller more reliable.

Signed-off-by: Steven J. Hill <steven.hill@cavium.com>
Acked-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13831/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Steven J. Hill 2016-07-26 10:26:26 -05:00 коммит произвёл Ralf Baechle
Родитель 8552b5b4da
Коммит 7e78db9975
1 изменённых файлов: 60 добавлений и 48 удалений

Просмотреть файл

@ -3,33 +3,27 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2004-2011 Cavium Networks
* Copyright (C) 2004-2016 Cavium Networks
* Copyright (C) 2008 Wind River Systems
*/
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/i2c.h>
#include <linux/usb.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
#include <linux/etherdevice.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/of_platform.h>
#include <linux/of_fdt.h>
#include <linux/libfdt.h>
#include <linux/usb/ehci_def.h>
#include <linux/usb/ehci_pdriver.h>
#include <linux/usb/ohci_pdriver.h>
#include <asm/octeon/octeon.h>
#include <asm/octeon/cvmx-rnm-defs.h>
#include <asm/octeon/cvmx-helper.h>
#include <asm/octeon/cvmx-helper-board.h>
#include <asm/octeon/cvmx-uctlx-defs.h>
#define CVMX_UAHCX_EHCI_USBCMD (CVMX_ADD_IO_SEG(0x00016F0000000010ull))
#define CVMX_UAHCX_OHCI_USBCMD (CVMX_ADD_IO_SEG(0x00016F0000000408ull))
/* Octeon Random Number Generator. */
static int __init octeon_rng_device_init(void)
{
@ -78,12 +72,36 @@ static DEFINE_MUTEX(octeon2_usb_clocks_mutex);
static int octeon2_usb_clock_start_cnt;
static int __init octeon2_usb_reset(void)
{
union cvmx_uctlx_clk_rst_ctl clk_rst_ctl;
u32 ucmd;
if (!OCTEON_IS_OCTEON2())
return 0;
clk_rst_ctl.u64 = cvmx_read_csr(CVMX_UCTLX_CLK_RST_CTL(0));
if (clk_rst_ctl.s.hrst) {
ucmd = cvmx_read64_uint32(CVMX_UAHCX_EHCI_USBCMD);
ucmd &= ~CMD_RUN;
cvmx_write64_uint32(CVMX_UAHCX_EHCI_USBCMD, ucmd);
mdelay(2);
ucmd |= CMD_RESET;
cvmx_write64_uint32(CVMX_UAHCX_EHCI_USBCMD, ucmd);
ucmd = cvmx_read64_uint32(CVMX_UAHCX_OHCI_USBCMD);
ucmd |= CMD_RUN;
cvmx_write64_uint32(CVMX_UAHCX_OHCI_USBCMD, ucmd);
}
return 0;
}
arch_initcall(octeon2_usb_reset);
static void octeon2_usb_clocks_start(struct device *dev)
{
u64 div;
union cvmx_uctlx_if_ena if_ena;
union cvmx_uctlx_clk_rst_ctl clk_rst_ctl;
union cvmx_uctlx_uphy_ctl_status uphy_ctl_status;
union cvmx_uctlx_uphy_portx_ctl_status port_ctl_status;
int i;
unsigned long io_clk_64_to_ns;
@ -131,6 +149,17 @@ static void octeon2_usb_clocks_start(struct device *dev)
if_ena.s.en = 1;
cvmx_write_csr(CVMX_UCTLX_IF_ENA(0), if_ena.u64);
for (i = 0; i <= 1; i++) {
port_ctl_status.u64 =
cvmx_read_csr(CVMX_UCTLX_UPHY_PORTX_CTL_STATUS(i, 0));
/* Set txvreftune to 15 to obtain compliant 'eye' diagram. */
port_ctl_status.s.txvreftune = 15;
port_ctl_status.s.txrisetune = 1;
port_ctl_status.s.txpreemphasistune = 1;
cvmx_write_csr(CVMX_UCTLX_UPHY_PORTX_CTL_STATUS(i, 0),
port_ctl_status.u64);
}
/* Step 3: Configure the reference clock, PHY, and HCLK */
clk_rst_ctl.u64 = cvmx_read_csr(CVMX_UCTLX_CLK_RST_CTL(0));
@ -218,29 +247,10 @@ static void octeon2_usb_clocks_start(struct device *dev)
clk_rst_ctl.s.p_por = 0;
cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
/* Step 5: Wait 1 ms for the PHY clock to start. */
mdelay(1);
/* Step 5: Wait 3 ms for the PHY clock to start. */
mdelay(3);
/*
* Step 6: Program the reset input from automatic test
* equipment field in the UPHY CSR
*/
uphy_ctl_status.u64 = cvmx_read_csr(CVMX_UCTLX_UPHY_CTL_STATUS(0));
uphy_ctl_status.s.ate_reset = 1;
cvmx_write_csr(CVMX_UCTLX_UPHY_CTL_STATUS(0), uphy_ctl_status.u64);
/* Step 7: Wait for at least 10ns. */
ndelay(10);
/* Step 8: Clear the ATE_RESET field in the UPHY CSR. */
uphy_ctl_status.s.ate_reset = 0;
cvmx_write_csr(CVMX_UCTLX_UPHY_CTL_STATUS(0), uphy_ctl_status.u64);
/*
* Step 9: Wait for at least 20ns for UPHY to output PHY clock
* signals and OHCI_CLK48
*/
ndelay(20);
/* Steps 6..9 for ATE only, are skipped. */
/* Step 10: Configure the OHCI_CLK48 and OHCI_CLK12 clocks. */
/* 10a */
@ -261,6 +271,20 @@ static void octeon2_usb_clocks_start(struct device *dev)
clk_rst_ctl.s.p_prst = 1;
cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
/* Step 11b */
udelay(1);
/* Step 11c */
clk_rst_ctl.s.p_prst = 0;
cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
/* Step 11d */
mdelay(1);
/* Step 11e */
clk_rst_ctl.s.p_prst = 1;
cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
/* Step 12: Wait 1 uS. */
udelay(1);
@ -269,21 +293,9 @@ static void octeon2_usb_clocks_start(struct device *dev)
cvmx_write_csr(CVMX_UCTLX_CLK_RST_CTL(0), clk_rst_ctl.u64);
end_clock:
/* Now we can set some other registers. */
for (i = 0; i <= 1; i++) {
port_ctl_status.u64 =
cvmx_read_csr(CVMX_UCTLX_UPHY_PORTX_CTL_STATUS(i, 0));
/* Set txvreftune to 15 to obtain compliant 'eye' diagram. */
port_ctl_status.s.txvreftune = 15;
port_ctl_status.s.txrisetune = 1;
port_ctl_status.s.txpreemphasistune = 1;
cvmx_write_csr(CVMX_UCTLX_UPHY_PORTX_CTL_STATUS(i, 0),
port_ctl_status.u64);
}
/* Set uSOF cycle period to 60,000 bits. */
cvmx_write_csr(CVMX_UCTLX_EHCI_FLA(0), 0x20ull);
exit:
mutex_unlock(&octeon2_usb_clocks_mutex);
}