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sdhci: tegra: Add missing TMCLK for data timeout

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commit b5a84ecf02 ("mmc: tegra: Add Tegra210 support")

Tegra210 and later has a separate sdmmc_legacy_tm (TMCLK) used by Tegra
SDMMC hawdware for data timeout to achive better timeout than using
SDCLK and using TMCLK is recommended.

USE_TMCLK_FOR_DATA_TIMEOUT bit in Tegra SDMMC register
SDHCI_TEGRA_VENDOR_SYS_SW_CTRL can be used to choose either TMCLK or
SDCLK for data timeout.

Default USE_TMCLK_FOR_DATA_TIMEOUT bit is set to 1 and TMCLK is used
for data timeout by Tegra SDMMC hardware and having TMCLK not enabled
is not recommended.

So, this patch adds quirk NVQUIRK_HAS_TMCLK for SoC having separate
timeout clock and keeps TMCLK enabled all the time.

Fixes: b5a84ecf02 ("mmc: tegra: Add Tegra210 support")
Cc: stable <stable@vger.kernel.org> # 5.4
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Link: https://lore.kernel.org/r/1598548861-32373-8-git-send-email-skomatineni@nvidia.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Sowjanya Komatineni 2020-08-27 10:21:01 -07:00 committed by Ulf Hansson
parent c956c0cd4f
commit 8048822bac
1 changed files with 51 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

53
drivers/mmc/host/sdhci-tegra.c
View File

@ -110,6 +110,12 @@
#define NVQUIRK_DIS_CARD_CLK_CONFIG_TAP BIT(8)
#define NVQUIRK_CQHCI_DCMD_R1B_CMD_TIMING BIT(9)
/*
* NVQUIRK_HAS_TMCLK is for SoC's having separate timeout clock for Tegra
* SDMMC hardware data timeout.
*/
#define NVQUIRK_HAS_TMCLK BIT(10)
/* SDMMC CQE Base Address for Tegra Host Ver 4.1 and Higher */
#define SDHCI_TEGRA_CQE_BASE_ADDR 0xF000
@ -140,6 +146,7 @@ struct sdhci_tegra_autocal_offsets {
struct sdhci_tegra {
const struct sdhci_tegra_soc_data *soc_data;
struct gpio_desc *power_gpio;
struct clk *tmclk;
bool ddr_signaling;
bool pad_calib_required;
bool pad_control_available;
@ -1433,7 +1440,8 @@ static const struct sdhci_tegra_soc_data soc_data_tegra210 = {
NVQUIRK_HAS_PADCALIB |
NVQUIRK_DIS_CARD_CLK_CONFIG_TAP |
NVQUIRK_ENABLE_SDR50 |
NVQUIRK_ENABLE_SDR104,
NVQUIRK_ENABLE_SDR104 |
NVQUIRK_HAS_TMCLK,
.min_tap_delay = 106,
.max_tap_delay = 185,
};
@ -1471,6 +1479,7 @@ static const struct sdhci_tegra_soc_data soc_data_tegra186 = {
NVQUIRK_DIS_CARD_CLK_CONFIG_TAP |
NVQUIRK_ENABLE_SDR50 |
NVQUIRK_ENABLE_SDR104 |
NVQUIRK_HAS_TMCLK |
NVQUIRK_CQHCI_DCMD_R1B_CMD_TIMING,
.min_tap_delay = 84,
.max_tap_delay = 136,
@ -1483,7 +1492,8 @@ static const struct sdhci_tegra_soc_data soc_data_tegra194 = {
NVQUIRK_HAS_PADCALIB |
NVQUIRK_DIS_CARD_CLK_CONFIG_TAP |
NVQUIRK_ENABLE_SDR50 |
NVQUIRK_ENABLE_SDR104,
NVQUIRK_ENABLE_SDR104 |
NVQUIRK_HAS_TMCLK,
.min_tap_delay = 96,
.max_tap_delay = 139,
};
@ -1611,6 +1621,43 @@ static int sdhci_tegra_probe(struct platform_device *pdev)
goto err_power_req;
}
/*
* Tegra210 has a separate SDMMC_LEGACY_TM clock used for host
* timeout clock and SW can choose TMCLK or SDCLK for hardware
* data timeout through the bit USE_TMCLK_FOR_DATA_TIMEOUT of
* the register SDHCI_TEGRA_VENDOR_SYS_SW_CTRL.
*
* USE_TMCLK_FOR_DATA_TIMEOUT bit default is set to 1 and SDMMC uses
* 12Mhz TMCLK which is advertised in host capability register.
* With TMCLK of 12Mhz provides maximum data timeout period that can
* be achieved is 11s better than using SDCLK for data timeout.
*
* So, TMCLK is set to 12Mhz and kept enabled all the time on SoC's
* supporting separate TMCLK.
*/
if (soc_data->nvquirks & NVQUIRK_HAS_TMCLK) {
clk = devm_clk_get(&pdev->dev, "tmclk");
if (IS_ERR(clk)) {
rc = PTR_ERR(clk);
if (rc == -EPROBE_DEFER)
goto err_power_req;
dev_warn(&pdev->dev, "failed to get tmclk: %d\n", rc);
clk = NULL;
}
clk_set_rate(clk, 12000000);
rc = clk_prepare_enable(clk);
if (rc) {
dev_err(&pdev->dev,
"failed to enable tmclk: %d\n", rc);
goto err_power_req;
}
tegra_host->tmclk = clk;
}
clk = devm_clk_get(mmc_dev(host->mmc), NULL);
if (IS_ERR(clk)) {
rc = PTR_ERR(clk);
@ -1654,6 +1701,7 @@ err_add_host:
err_rst_get:
clk_disable_unprepare(pltfm_host->clk);
err_clk_get:
clk_disable_unprepare(tegra_host->tmclk);
err_power_req:
err_parse_dt:
sdhci_pltfm_free(pdev);
@ -1671,6 +1719,7 @@ static int sdhci_tegra_remove(struct platform_device *pdev)
reset_control_assert(tegra_host->rst);
usleep_range(2000, 4000);
clk_disable_unprepare(pltfm_host->clk);
clk_disable_unprepare(tegra_host->tmclk);
sdhci_pltfm_free(pdev);