linux/drivers/mmc/host/tmio_mmc.c

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// SPDX-License-Identifier: GPL-2.0
/*
* Driver for the MMC / SD / SDIO cell found in:
*
* TC6393XB TC6391XB TC6387XB T7L66XB ASIC3
*
* Copyright (C) 2017 Renesas Electronics Corporation
* Copyright (C) 2017 Horms Solutions, Simon Horman
* Copyright (C) 2007 Ian Molton
* Copyright (C) 2004 Ian Molton
*/
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/mfd/core.h>
#include <linux/mfd/tmio.h>
#include <linux/mmc/host.h>
#include <linux/module.h>
#include <linux/pagemap.h>
#include <linux/scatterlist.h>
mmc: tmio_mmc: handle missing HW interrupts When doing excessive hotplug, e.g., repeated insert/eject operations, the hardware may get confused to a point where no CMDTIMEOUT/CMDRESPEND interrupts are generated any more. As a result requests get stuck, e.g.: [ 360.351562] INFO: task kworker/u:0:5 blocked for more than 120 seconds. [ 360.351562] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 360.359375] kworker/u:0 D c020c2b4 0 5 2 0x00000000 [ 360.367187] Backtrace: [ 360.367187] [<c020bfb0>] (schedule+0x0/0x340) from [<c020c480>] (schedule_timeout+0x20/0x190) [ 360.375000] r8:c702fd70 r7:00000002 r6:c702e000 r5:c702fdc4 r4:7fffffff [ 360.375000] r3:c701e040 [ 360.382812] [<c020c460>] (schedule_timeout+0x0/0x190) from [<c020be78>] (wait_for_common+0xc4/0x150) [ 360.390625] r6:c702e000 r5:c702fdc4 r4:7fffffff [ 360.390625] [<c020bdb4>] (wait_for_common+0x0/0x150) from [<c020bfac>] (wait_for_completion+0x18/0x1c) [ 360.398437] [<c020bf94>] (wait_for_completion+0x0/0x1c) from [<c0185590>] (mmc_wait_for_req+0x214/0x234) [ 360.406250] [<c018537c>] (mmc_wait_for_req+0x0/0x234) from [<c01889d0>] (mmc_sd_switch+0xfc/0x114) [ 360.414062] r7:c702fe4c r6:c702fe20 r5:c7179800 r4:00fffff0 [ 360.421875] [<c01888d4>] (mmc_sd_switch+0x0/0x114) from [<c0187f70>] (mmc_sd_setup_card+0x260/0x384) [ 360.429687] [<c0187d10>] (mmc_sd_setup_card+0x0/0x384) from [<c01885e0>] (mmc_sd_init_card+0x13c/0x1e0) [ 360.437500] [<c01884a4>] (mmc_sd_init_card+0x0/0x1e0) from [<c01887a8>] (mmc_attach_sd+0x124/0x1a8) [ 360.445312] r8:c02db404 r7:ffffff92 r6:c702ff34 r5:c6007da8 r4:c6007c00 [ 360.453125] [<c0188684>] (mmc_attach_sd+0x0/0x1a8) from [<c0185140>] (mmc_rescan+0x248/0x2f0) [ 360.460937] r5:c6007da8 r4:c6007c00 [ 360.468750] [<c0184ef8>] (mmc_rescan+0x0/0x2f0) from [<c00467f0>] (process_one_work+0x1ec/0x318) [ 360.476562] r7:c6007da8 r6:00000000 r5:c710ec00 r4:c701bde0 [ 360.484375] [<c0046604>] (process_one_work+0x0/0x318) from [<c0047fb0>] (worker_thread+0x1b0/0x2cc) [ 360.492187] [<c0047e00>] (worker_thread+0x0/0x2cc) from [<c004b338>] (kthread+0x8c/0x94) [ 360.500000] [<c004b2ac>] (kthread+0x0/0x94) from [<c0037fc4>] (do_exit+0x0/0x590) [ 360.507812] r7:00000013 r6:c0037fc4 r5:c004b2ac r4:c7021f00 This patch addresses this problem by introducing timeouts for outstanding interrupts. If a hardware interrupt is missing, a soft reset will be performed to bring the hardware back to a working state. Tested with the SDHI hardware block in sh7372 / AP4EVB. Signed-off-by: Arnd Hannemann <arnd@arndnet.de> Signed-off-by: Chris Ball <cjb@laptop.org>
2011-01-05 22:36:14 +00:00
#include "tmio_mmc.h"
/* Registers specific to this variant */
#define CTL_SDIO_REGS 0x100
#define CTL_CLK_AND_WAIT_CTL 0x138
#define CTL_RESET_SDIO 0x1e0
static void tmio_mmc_clk_start(struct tmio_mmc_host *host)
{
sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, CLK_CTL_SCLKEN |
sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
usleep_range(10000, 11000);
sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0100);
usleep_range(10000, 11000);
}
static void tmio_mmc_clk_stop(struct tmio_mmc_host *host)
{
sd_ctrl_write16(host, CTL_CLK_AND_WAIT_CTL, 0x0000);
usleep_range(10000, 11000);
sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
usleep_range(10000, 11000);
}
static void tmio_mmc_set_clock(struct tmio_mmc_host *host,
unsigned int new_clock)
{
unsigned int divisor;
u32 clk = 0;
int clk_sel;
if (new_clock == 0) {
tmio_mmc_clk_stop(host);
return;
}
divisor = host->pdata->hclk / new_clock;
/* bit7 set: 1/512, ... bit0 set: 1/4, all bits clear: 1/2 */
clk_sel = (divisor <= 1);
clk = clk_sel ? 0 : (roundup_pow_of_two(divisor) >> 2);
host->pdata->set_clk_div(host->pdev, clk_sel);
sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, ~CLK_CTL_SCLKEN &
sd_ctrl_read16(host, CTL_SD_CARD_CLK_CTL));
sd_ctrl_write16(host, CTL_SD_CARD_CLK_CTL, clk & CLK_CTL_DIV_MASK);
usleep_range(10000, 11000);
tmio_mmc_clk_start(host);
}
static void tmio_mmc_reset(struct tmio_mmc_host *host)
{
/* FIXME - should we set stop clock reg here */
sd_ctrl_write16(host, CTL_RESET_SD, 0x0000);
sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0000);
usleep_range(10000, 11000);
sd_ctrl_write16(host, CTL_RESET_SD, 0x0001);
sd_ctrl_write16(host, CTL_RESET_SDIO, 0x0001);
usleep_range(10000, 11000);
if (host->pdata->flags & TMIO_MMC_SDIO_IRQ) {
sd_ctrl_write16(host, CTL_SDIO_IRQ_MASK, host->sdio_irq_mask);
sd_ctrl_write16(host, CTL_TRANSACTION_CTL, 0x0001);
}
}
#ifdef CONFIG_PM_SLEEP
static int tmio_mmc_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
const struct mfd_cell *cell = mfd_get_cell(pdev);
int ret;
ret = pm_runtime_force_suspend(dev);
/* Tell MFD core it can disable us now.*/
if (!ret && cell->disable)
cell->disable(pdev);
return ret;
}
static int tmio_mmc_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
const struct mfd_cell *cell = mfd_get_cell(pdev);
int ret = 0;
/* Tell the MFD core we are ready to be enabled */
if (cell->resume)
ret = cell->resume(pdev);
if (!ret)
ret = pm_runtime_force_resume(dev);
return ret;
}
#endif
static int tmio_mmc_probe(struct platform_device *pdev)
{
const struct mfd_cell *cell = mfd_get_cell(pdev);
struct tmio_mmc_data *pdata;
struct tmio_mmc_host *host;
struct resource *res;
int ret = -EINVAL, irq;
if (pdev->num_resources != 2)
goto out;
pdata = pdev->dev.platform_data;
if (!pdata || !pdata->hclk)
goto out;
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
ret = irq;
goto out;
}
/* Tell the MFD core we are ready to be enabled */
if (cell->enable) {
ret = cell->enable(pdev);
if (ret)
goto out;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
ret = -EINVAL;
goto cell_disable;
}
host = tmio_mmc_host_alloc(pdev, pdata);
if (IS_ERR(host)) {
ret = PTR_ERR(host);
goto cell_disable;
}
/* SD control register space size is 0x200, 0x400 for bus_shift=1 */
host->bus_shift = resource_size(res) >> 10;
host->set_clock = tmio_mmc_set_clock;
host->reset = tmio_mmc_reset;
host->mmc->f_max = pdata->hclk;
host->mmc->f_min = pdata->hclk / 512;
ret = tmio_mmc_host_probe(host);
if (ret)
goto host_free;
ret = devm_request_irq(&pdev->dev, irq, tmio_mmc_irq,
IRQF_TRIGGER_FALLING,
dev_name(&pdev->dev), host);
if (ret)
goto host_remove;
pr_info("%s at 0x%08lx irq %d\n", mmc_hostname(host->mmc),
(unsigned long)host->ctl, irq);
return 0;
host_remove:
tmio_mmc_host_remove(host);
host_free:
tmio_mmc_host_free(host);
cell_disable:
if (cell->disable)
cell->disable(pdev);
out:
return ret;
}
static int tmio_mmc_remove(struct platform_device *pdev)
{
const struct mfd_cell *cell = mfd_get_cell(pdev);
struct tmio_mmc_host *host = platform_get_drvdata(pdev);
tmio_mmc_host_remove(host);
if (cell->disable)
cell->disable(pdev);
return 0;
}
/* ------------------- device registration ----------------------- */
static const struct dev_pm_ops tmio_mmc_dev_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(tmio_mmc_suspend, tmio_mmc_resume)
SET_RUNTIME_PM_OPS(tmio_mmc_host_runtime_suspend,
tmio_mmc_host_runtime_resume, NULL)
};
static struct platform_driver tmio_mmc_driver = {
.driver = {
.name = "tmio-mmc",
.pm = &tmio_mmc_dev_pm_ops,
},
.probe = tmio_mmc_probe,
.remove = tmio_mmc_remove,
};
module_platform_driver(tmio_mmc_driver);
MODULE_DESCRIPTION("Toshiba TMIO SD/MMC driver");
MODULE_AUTHOR("Ian Molton <spyro@f2s.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:tmio-mmc");