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Commit 8ee5fc0e authored by Faiz Abbas's avatar Faiz Abbas Committed by Ulf Hansson
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mmc: sdhci_am654: Update OTAPDLY writes 

According to the latest AM65x Data Manual[1], a different output tap
delay value is optimum for a given speed mode. Therefore, deprecate the
ti,otap-del-sel binding and introduce a new binding for each of the
possible MMC/SD speed modes. If the legacy mode is not found, fall back
to old binding to maintain dts compatibility.

[1] http://www.ti.com/lit/gpn/am6526Signed-off-by: default avatarFaiz Abbas <faiz_abbas@ti.com>
Acked-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20200108150920.14547-3-faiz_abbas@ti.comSigned-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 70fd681e
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Showing with 107 additions and 18 deletions
drivers/mmc/host/sdhci_am654.c
View file @ 8ee5fc0e
......@@ -81,7 +81,8 @@ static struct regmap_config sdhci_am654_regmap_config = {
struct sdhci_am654_data {
struct regmap *base;
int otap_del_sel;
bool legacy_otapdly;
int otap_del_sel[11];
int trm_icp;
int drv_strength;
bool dll_on;
......@@ -98,11 +99,34 @@ struct sdhci_am654_driver_data {
#define DLL_PRESENT (1 << 3)
};
struct timing_data {
const char *binding;
u32 capability;
};
static const struct timing_data td[] = {
[MMC_TIMING_LEGACY] = {"ti,otap-del-sel-legacy", 0},
[MMC_TIMING_MMC_HS] = {"ti,otap-del-sel-mmc-hs", MMC_CAP_MMC_HIGHSPEED},
[MMC_TIMING_SD_HS] = {"ti,otap-del-sel-sd-hs", MMC_CAP_SD_HIGHSPEED},
[MMC_TIMING_UHS_SDR12] = {"ti,otap-del-sel-sdr12", MMC_CAP_UHS_SDR12},
[MMC_TIMING_UHS_SDR25] = {"ti,otap-del-sel-sdr25", MMC_CAP_UHS_SDR25},
[MMC_TIMING_UHS_SDR50] = {"ti,otap-del-sel-sdr50", MMC_CAP_UHS_SDR50},
[MMC_TIMING_UHS_SDR104] = {"ti,otap-del-sel-sdr104",
MMC_CAP_UHS_SDR104},
[MMC_TIMING_UHS_DDR50] = {"ti,otap-del-sel-ddr50", MMC_CAP_UHS_DDR50},
[MMC_TIMING_MMC_DDR52] = {"ti,otap-del-sel-ddr52", MMC_CAP_DDR},
[MMC_TIMING_MMC_HS200] = {"ti,otap-del-sel-hs200", MMC_CAP2_HS200},
[MMC_TIMING_MMC_HS400] = {"ti,otap-del-sel-hs400", MMC_CAP2_HS400},
};
static void sdhci_am654_set_clock(struct sdhci_host *host, unsigned int clock)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_am654_data *sdhci_am654 = sdhci_pltfm_priv(pltfm_host);
unsigned char timing = host->mmc->ios.timing;
int sel50, sel100, freqsel;
u32 otap_del_sel;
u32 otap_del_ena;
u32 mask, val;
int ret;
......@@ -116,22 +140,29 @@ static void sdhci_am654_set_clock(struct sdhci_host *host, unsigned int clock)
if (clock > CLOCK_TOO_SLOW_HZ) {
/* Setup DLL Output TAP delay */
if (sdhci_am654->legacy_otapdly)
otap_del_sel = sdhci_am654->otap_del_sel[0];
else
otap_del_sel = sdhci_am654->otap_del_sel[timing];
otap_del_ena = (timing > MMC_TIMING_UHS_SDR25) ? 1 : 0;
mask = OTAPDLYENA_MASK | OTAPDLYSEL_MASK;
val = (1 << OTAPDLYENA_SHIFT) |
(sdhci_am654->otap_del_sel << OTAPDLYSEL_SHIFT);
regmap_update_bits(sdhci_am654->base, PHY_CTRL4, mask, val);
val = (otap_del_ena << OTAPDLYENA_SHIFT) |
(otap_del_sel << OTAPDLYSEL_SHIFT);
/* Write to STRBSEL for HS400 speed mode */
if (host->mmc->ios.timing == MMC_TIMING_MMC_HS400) {
if (timing == MMC_TIMING_MMC_HS400) {
if (sdhci_am654->flags & STRBSEL_4_BIT)
mask = STRBSEL_4BIT_MASK;
mask |= STRBSEL_4BIT_MASK;
else
mask = STRBSEL_8BIT_MASK;
mask |= STRBSEL_8BIT_MASK;
regmap_update_bits(sdhci_am654->base, PHY_CTRL4, mask,
sdhci_am654->strb_sel <<
STRBSEL_SHIFT);
val |= sdhci_am654->strb_sel << STRBSEL_SHIFT;
}
regmap_update_bits(sdhci_am654->base, PHY_CTRL4, mask, val);
if (sdhci_am654->flags & FREQSEL_2_BIT) {
switch (clock) {
case 200000000:
......@@ -198,11 +229,19 @@ static void sdhci_j721e_4bit_set_clock(struct sdhci_host *host,
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_am654_data *sdhci_am654 = sdhci_pltfm_priv(pltfm_host);
int val, mask;
unsigned char timing = host->mmc->ios.timing;
u32 otap_del_sel;
u32 mask, val;
/* Setup DLL Output TAP delay */
if (sdhci_am654->legacy_otapdly)
otap_del_sel = sdhci_am654->otap_del_sel[0];
else
otap_del_sel = sdhci_am654->otap_del_sel[timing];
mask = OTAPDLYENA_MASK | OTAPDLYSEL_MASK;
val = (1 << OTAPDLYENA_SHIFT) |
(sdhci_am654->otap_del_sel << OTAPDLYSEL_SHIFT);
val = (0x1 << OTAPDLYENA_SHIFT) |
(otap_del_sel << OTAPDLYSEL_SHIFT);
regmap_update_bits(sdhci_am654->base, PHY_CTRL4, mask, val);
sdhci_set_clock(host, clock);
......@@ -371,6 +410,55 @@ static int sdhci_am654_cqe_add_host(struct sdhci_host *host)
return ret;
}
static int sdhci_am654_get_otap_delay(struct sdhci_host *host,
struct sdhci_am654_data *sdhci_am654)
{
struct device *dev = mmc_dev(host->mmc);
int i;
int ret;
ret = device_property_read_u32(dev, td[MMC_TIMING_LEGACY].binding,
&sdhci_am654->otap_del_sel[MMC_TIMING_LEGACY]);
if (ret) {
/*
* ti,otap-del-sel-legacy is mandatory, look for old binding
* if not found.
*/
ret = device_property_read_u32(dev, "ti,otap-del-sel",
&sdhci_am654->otap_del_sel[0]);
if (ret) {
dev_err(dev, "Couldn't find otap-del-sel\n");
return ret;
}
dev_info(dev, "Using legacy binding ti,otap-del-sel\n");
sdhci_am654->legacy_otapdly = true;
return 0;
}
for (i = MMC_TIMING_MMC_HS; i <= MMC_TIMING_MMC_HS400; i++) {
ret = device_property_read_u32(dev, td[i].binding,
&sdhci_am654->otap_del_sel[i]);
if (ret) {
dev_dbg(dev, "Couldn't find %s\n",
td[i].binding);
/*
* Remove the corresponding capability
* if an otap-del-sel value is not found
*/
if (i <= MMC_TIMING_MMC_DDR52)
host->mmc->caps &= ~td[i].capability;
else
host->mmc->caps2 &= ~td[i].capability;
}
}
return 0;
}
static int sdhci_am654_init(struct sdhci_host *host)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
......@@ -419,6 +507,10 @@ static int sdhci_am654_init(struct sdhci_host *host)
if (ret)
goto err_cleanup_host;
ret = sdhci_am654_get_otap_delay(host, sdhci_am654);
if (ret)
goto err_cleanup_host;
ret = __sdhci_add_host(host);
if (ret)
goto err_cleanup_host;
......@@ -437,11 +529,6 @@ static int sdhci_am654_get_of_property(struct platform_device *pdev,
int drv_strength;
int ret;
ret = device_property_read_u32(dev, "ti,otap-del-sel",
&sdhci_am654->otap_del_sel);
if (ret)
return ret;
if (sdhci_am654->flags & DLL_PRESENT) {
ret = device_property_read_u32(dev, "ti,trm-icp",
&sdhci_am654->trm_icp);
......
include/linux/mmc/host.h
View file @ 8ee5fc0e
......@@ -322,6 +322,8 @@ struct mmc_host {
#define MMC_CAP_3_3V_DDR (1 << 11) /* Host supports eMMC DDR 3.3V */
#define MMC_CAP_1_8V_DDR (1 << 12) /* Host supports eMMC DDR 1.8V */
#define MMC_CAP_1_2V_DDR (1 << 13) /* Host supports eMMC DDR 1.2V */
#define MMC_CAP_DDR (MMC_CAP_3_3V_DDR | MMC_CAP_1_8V_DDR | \
MMC_CAP_1_2V_DDR)
#define MMC_CAP_POWER_OFF_CARD (1 << 14) /* Can power off after boot */
#define MMC_CAP_BUS_WIDTH_TEST (1 << 15) /* CMD14/CMD19 bus width ok */
#define MMC_CAP_UHS_SDR12 (1 << 16) /* Host supports UHS SDR12 mode */
......
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