linux-stable/drivers/mmc/host/sdhci-brcmstb.c
Al Cooper 2fefc7c5f7 mmc: sdhci-brcmstb: Fix incorrect switch to HS mode
When switching from any MMC speed mode that requires 1.8v
(HS200, HS400 and HS400ES) to High Speed (HS) mode, the system
ends up configured for SDR12 with a 50MHz clock which is an illegal
mode.

This happens because the SDHCI_CTRL_VDD_180 bit in the
SDHCI_HOST_CONTROL2 register is left set and when this bit is
set, the speed mode is controlled by the SDHCI_CTRL_UHS field
in the SDHCI_HOST_CONTROL2 register. The SDHCI_CTRL_UHS field
will end up being set to 0 (SDR12) by sdhci_set_uhs_signaling()
because there is no UHS mode being set.

The fix is to change sdhci_set_uhs_signaling() to set the
SDHCI_CTRL_UHS field to SDR25 (which is the same as HS) for
any switch to HS mode.

This was found on a new eMMC controller that does strict checking
of the speed mode and the corresponding clock rate. It caused the
switch to HS400 mode to fail because part of the sequence to switch
to HS400 requires a switch from HS200 to HS before going to HS400.

This issue was previously fixed by commit c894e33ddc ("mmc: sdhci:
Fix incorrect switch to HS mode") and later removed by commit
07bcc41156 ("Revert \"mmc: sdhci: Fix incorrect switch to HS mode\"")
because it caused failures with some SD cards on AM65X systems. The
fix will now be done in a platform specific callback instead of
common sdhci code.

Signed-off-by: Al Cooper <alcooperx@gmail.com>
Suggested-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20200113210706.11972-7-alcooperx@gmail.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2020-01-20 12:01:19 +01:00

343 lines
8.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* sdhci-brcmstb.c Support for SDHCI on Broadcom BRCMSTB SoC's
*
* Copyright (C) 2015 Broadcom Corporation
*/
#include <linux/io.h>
#include <linux/mmc/host.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/bitops.h>
#include <linux/delay.h>
#include "sdhci-pltfm.h"
#include "cqhci.h"
#define SDHCI_VENDOR 0x78
#define SDHCI_VENDOR_ENHANCED_STRB 0x1
#define BRCMSTB_PRIV_FLAGS_NO_64BIT BIT(0)
#define BRCMSTB_PRIV_FLAGS_BROKEN_TIMEOUT BIT(1)
#define SDHCI_ARASAN_CQE_BASE_ADDR 0x200
struct sdhci_brcmstb_priv {
void __iomem *cfg_regs;
bool has_cqe;
};
struct brcmstb_match_priv {
void (*hs400es)(struct mmc_host *mmc, struct mmc_ios *ios);
struct sdhci_ops *ops;
unsigned int flags;
};
static void sdhci_brcmstb_hs400es(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct sdhci_host *host = mmc_priv(mmc);
u32 reg;
dev_dbg(mmc_dev(mmc), "%s(): Setting HS400-Enhanced-Strobe mode\n",
__func__);
reg = readl(host->ioaddr + SDHCI_VENDOR);
if (ios->enhanced_strobe)
reg |= SDHCI_VENDOR_ENHANCED_STRB;
else
reg &= ~SDHCI_VENDOR_ENHANCED_STRB;
writel(reg, host->ioaddr + SDHCI_VENDOR);
}
static void sdhci_brcmstb_set_clock(struct sdhci_host *host, unsigned int clock)
{
u16 clk;
host->mmc->actual_clock = 0;
clk = sdhci_calc_clk(host, clock, &host->mmc->actual_clock);
sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
if (clock == 0)
return;
sdhci_enable_clk(host, clk);
}
static void sdhci_brcmstb_set_uhs_signaling(struct sdhci_host *host,
unsigned int timing)
{
u16 ctrl_2;
dev_dbg(mmc_dev(host->mmc), "%s: Setting UHS signaling for %d timing\n",
__func__, timing);
ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
/* Select Bus Speed Mode for host */
ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
if ((timing == MMC_TIMING_MMC_HS200) ||
(timing == MMC_TIMING_UHS_SDR104))
ctrl_2 |= SDHCI_CTRL_UHS_SDR104;
else if (timing == MMC_TIMING_UHS_SDR12)
ctrl_2 |= SDHCI_CTRL_UHS_SDR12;
else if (timing == MMC_TIMING_SD_HS ||
timing == MMC_TIMING_MMC_HS ||
timing == MMC_TIMING_UHS_SDR25)
ctrl_2 |= SDHCI_CTRL_UHS_SDR25;
else if (timing == MMC_TIMING_UHS_SDR50)
ctrl_2 |= SDHCI_CTRL_UHS_SDR50;
else if ((timing == MMC_TIMING_UHS_DDR50) ||
(timing == MMC_TIMING_MMC_DDR52))
ctrl_2 |= SDHCI_CTRL_UHS_DDR50;
else if (timing == MMC_TIMING_MMC_HS400)
ctrl_2 |= SDHCI_CTRL_HS400; /* Non-standard */
sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
}
static void sdhci_brcmstb_dumpregs(struct mmc_host *mmc)
{
sdhci_dumpregs(mmc_priv(mmc));
}
static void sdhci_brcmstb_cqe_enable(struct mmc_host *mmc)
{
struct sdhci_host *host = mmc_priv(mmc);
u32 reg;
reg = sdhci_readl(host, SDHCI_PRESENT_STATE);
while (reg & SDHCI_DATA_AVAILABLE) {
sdhci_readl(host, SDHCI_BUFFER);
reg = sdhci_readl(host, SDHCI_PRESENT_STATE);
}
sdhci_cqe_enable(mmc);
}
static const struct cqhci_host_ops sdhci_brcmstb_cqhci_ops = {
.enable = sdhci_brcmstb_cqe_enable,
.disable = sdhci_cqe_disable,
.dumpregs = sdhci_brcmstb_dumpregs,
};
static struct sdhci_ops sdhci_brcmstb_ops = {
.set_clock = sdhci_set_clock,
.set_bus_width = sdhci_set_bus_width,
.reset = sdhci_reset,
.set_uhs_signaling = sdhci_set_uhs_signaling,
};
static struct sdhci_ops sdhci_brcmstb_ops_7216 = {
.set_clock = sdhci_brcmstb_set_clock,
.set_bus_width = sdhci_set_bus_width,
.reset = sdhci_reset,
.set_uhs_signaling = sdhci_brcmstb_set_uhs_signaling,
};
static struct brcmstb_match_priv match_priv_7425 = {
.flags = BRCMSTB_PRIV_FLAGS_NO_64BIT |
BRCMSTB_PRIV_FLAGS_BROKEN_TIMEOUT,
.ops = &sdhci_brcmstb_ops,
};
static struct brcmstb_match_priv match_priv_7445 = {
.flags = BRCMSTB_PRIV_FLAGS_BROKEN_TIMEOUT,
.ops = &sdhci_brcmstb_ops,
};
static const struct brcmstb_match_priv match_priv_7216 = {
.hs400es = sdhci_brcmstb_hs400es,
.ops = &sdhci_brcmstb_ops_7216,
};
static const struct of_device_id sdhci_brcm_of_match[] = {
{ .compatible = "brcm,bcm7425-sdhci", .data = &match_priv_7425 },
{ .compatible = "brcm,bcm7445-sdhci", .data = &match_priv_7445 },
{ .compatible = "brcm,bcm7216-sdhci", .data = &match_priv_7216 },
{},
};
static u32 sdhci_brcmstb_cqhci_irq(struct sdhci_host *host, u32 intmask)
{
int cmd_error = 0;
int data_error = 0;
if (!sdhci_cqe_irq(host, intmask, &cmd_error, &data_error))
return intmask;
cqhci_irq(host->mmc, intmask, cmd_error, data_error);
return 0;
}
static int sdhci_brcmstb_add_host(struct sdhci_host *host,
struct sdhci_brcmstb_priv *priv)
{
struct cqhci_host *cq_host;
bool dma64;
int ret;
if (!priv->has_cqe)
return sdhci_add_host(host);
dev_dbg(mmc_dev(host->mmc), "CQE is enabled\n");
host->mmc->caps2 |= MMC_CAP2_CQE | MMC_CAP2_CQE_DCMD;
ret = sdhci_setup_host(host);
if (ret)
return ret;
cq_host = devm_kzalloc(mmc_dev(host->mmc),
sizeof(*cq_host), GFP_KERNEL);
if (!cq_host) {
ret = -ENOMEM;
goto cleanup;
}
cq_host->mmio = host->ioaddr + SDHCI_ARASAN_CQE_BASE_ADDR;
cq_host->ops = &sdhci_brcmstb_cqhci_ops;
dma64 = host->flags & SDHCI_USE_64_BIT_DMA;
if (dma64) {
dev_dbg(mmc_dev(host->mmc), "Using 64 bit DMA\n");
cq_host->caps |= CQHCI_TASK_DESC_SZ_128;
cq_host->quirks |= CQHCI_QUIRK_SHORT_TXFR_DESC_SZ;
}
ret = cqhci_init(cq_host, host->mmc, dma64);
if (ret)
goto cleanup;
ret = __sdhci_add_host(host);
if (ret)
goto cleanup;
return 0;
cleanup:
sdhci_cleanup_host(host);
return ret;
}
static int sdhci_brcmstb_probe(struct platform_device *pdev)
{
const struct brcmstb_match_priv *match_priv;
struct sdhci_pltfm_data brcmstb_pdata;
struct sdhci_pltfm_host *pltfm_host;
const struct of_device_id *match;
struct sdhci_brcmstb_priv *priv;
struct sdhci_host *host;
struct resource *iomem;
bool has_cqe = false;
struct clk *clk;
int res;
match = of_match_node(sdhci_brcm_of_match, pdev->dev.of_node);
match_priv = match->data;
dev_dbg(&pdev->dev, "Probe found match for %s\n", match->compatible);
clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(clk)) {
if (PTR_ERR(clk) == -EPROBE_DEFER)
return -EPROBE_DEFER;
dev_err(&pdev->dev, "Clock not found in Device Tree\n");
clk = NULL;
}
res = clk_prepare_enable(clk);
if (res)
return res;
memset(&brcmstb_pdata, 0, sizeof(brcmstb_pdata));
if (device_property_read_bool(&pdev->dev, "supports-cqe")) {
has_cqe = true;
match_priv->ops->irq = sdhci_brcmstb_cqhci_irq;
}
brcmstb_pdata.ops = match_priv->ops;
host = sdhci_pltfm_init(pdev, &brcmstb_pdata,
sizeof(struct sdhci_brcmstb_priv));
if (IS_ERR(host)) {
res = PTR_ERR(host);
goto err_clk;
}
pltfm_host = sdhci_priv(host);
priv = sdhci_pltfm_priv(pltfm_host);
priv->has_cqe = has_cqe;
/* Map in the non-standard CFG registers */
iomem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
priv->cfg_regs = devm_ioremap_resource(&pdev->dev, iomem);
if (IS_ERR(priv->cfg_regs)) {
res = PTR_ERR(priv->cfg_regs);
goto err;
}
sdhci_get_of_property(pdev);
res = mmc_of_parse(host->mmc);
if (res)
goto err;
/*
* If the chip has enhanced strobe and it's enabled, add
* callback
*/
if (match_priv->hs400es &&
(host->mmc->caps2 & MMC_CAP2_HS400_ES))
host->mmc_host_ops.hs400_enhanced_strobe = match_priv->hs400es;
/*
* Supply the existing CAPS, but clear the UHS modes. This
* will allow these modes to be specified by device tree
* properties through mmc_of_parse().
*/
host->caps = sdhci_readl(host, SDHCI_CAPABILITIES);
if (match_priv->flags & BRCMSTB_PRIV_FLAGS_NO_64BIT)
host->caps &= ~SDHCI_CAN_64BIT;
host->caps1 = sdhci_readl(host, SDHCI_CAPABILITIES_1);
host->caps1 &= ~(SDHCI_SUPPORT_SDR50 | SDHCI_SUPPORT_SDR104 |
SDHCI_SUPPORT_DDR50);
host->quirks |= SDHCI_QUIRK_MISSING_CAPS;
if (match_priv->flags & BRCMSTB_PRIV_FLAGS_BROKEN_TIMEOUT)
host->quirks |= SDHCI_QUIRK_BROKEN_TIMEOUT_VAL;
res = sdhci_brcmstb_add_host(host, priv);
if (res)
goto err;
pltfm_host->clk = clk;
return res;
err:
sdhci_pltfm_free(pdev);
err_clk:
clk_disable_unprepare(clk);
return res;
}
static void sdhci_brcmstb_shutdown(struct platform_device *pdev)
{
int ret;
ret = sdhci_pltfm_unregister(pdev);
if (ret)
dev_err(&pdev->dev, "failed to shutdown\n");
}
MODULE_DEVICE_TABLE(of, sdhci_brcm_of_match);
static struct platform_driver sdhci_brcmstb_driver = {
.driver = {
.name = "sdhci-brcmstb",
.pm = &sdhci_pltfm_pmops,
.of_match_table = of_match_ptr(sdhci_brcm_of_match),
},
.probe = sdhci_brcmstb_probe,
.remove = sdhci_pltfm_unregister,
.shutdown = sdhci_brcmstb_shutdown,
};
module_platform_driver(sdhci_brcmstb_driver);
MODULE_DESCRIPTION("SDHCI driver for Broadcom BRCMSTB SoCs");
MODULE_AUTHOR("Broadcom");
MODULE_LICENSE("GPL v2");