[PATCH v3 06/20] mmc: am654_sdhci: Add support for input tap delay
Aswath Govindraju
a-govindraju at ti.com
Thu Jan 21 13:40:38 CET 2021
From: Faiz Abbas <faiz_abbas at ti.com>
DLL need only be enabled for speed modes and clock frequencies at or
above 50 MHz. For speed modes that don't enable the DLL, we need to
configure a static input delay value. This involves reading an optional
itap-del-sel-* value from the device tree and configuring it for the
appropriate speed mode.
Therefore, move all dll configurations to their own functions and gate it
with 50 MHz speed and a minimum mode. If both these conditions are not
satisfied then configure delay chain modes.
Signed-off-by: Faiz Abbas <faiz_abbas at ti.com>
Signed-off-by: Aswath Govindraju <a-govindraju at ti.com>
---
drivers/mmc/am654_sdhci.c | 241 +++++++++++++++++++++++++-------------
1 file changed, 161 insertions(+), 80 deletions(-)
diff --git a/drivers/mmc/am654_sdhci.c b/drivers/mmc/am654_sdhci.c
index 5790fa3d0dbf..b82558254ebb 100644
--- a/drivers/mmc/am654_sdhci.c
+++ b/drivers/mmc/am654_sdhci.c
@@ -62,6 +62,16 @@
#define CALDONE_MASK BIT(CALDONE_SHIFT)
#define RETRIM_SHIFT 17
#define RETRIM_MASK BIT(RETRIM_SHIFT)
+#define SELDLYTXCLK_SHIFT 17
+#define SELDLYTXCLK_MASK BIT(SELDLYTXCLK_SHIFT)
+#define SELDLYRXCLK_SHIFT 16
+#define SELDLYRXCLK_MASK BIT(SELDLYRXCLK_SHIFT)
+#define ITAPDLYSEL_SHIFT 0
+#define ITAPDLYSEL_MASK GENMASK(4, 0)
+#define ITAPDLYENA_SHIFT 8
+#define ITAPDLYENA_MASK BIT(ITAPDLYENA_SHIFT)
+#define ITAPCHGWIN_SHIFT 9
+#define ITAPCHGWIN_MASK BIT(ITAPCHGWIN_SHIFT)
#define DRIVER_STRENGTH_50_OHM 0x0
#define DRIVER_STRENGTH_33_OHM 0x1
@@ -70,6 +80,7 @@
#define DRIVER_STRENGTH_40_OHM 0x4
#define AM654_SDHCI_MIN_FREQ 400000
+#define CLOCK_TOO_SLOW_HZ 50000000
struct am654_sdhci_plat {
struct mmc_config cfg;
@@ -77,6 +88,7 @@ struct am654_sdhci_plat {
struct regmap *base;
bool non_removable;
u32 otap_del_sel[MMC_MODES_END];
+ u32 itap_del_sel[MMC_MODES_END];
u32 trm_icp;
u32 drv_strength;
u32 strb_sel;
@@ -89,22 +101,45 @@ struct am654_sdhci_plat {
};
struct timing_data {
- const char *binding;
+ const char *otap_binding;
+ const char *itap_binding;
u32 capability;
};
static const struct timing_data td[] = {
- [MMC_LEGACY] = {"ti,otap-del-sel-legacy", 0},
- [MMC_HS] = {"ti,otap-del-sel-mmc-hs", MMC_CAP(MMC_HS)},
- [SD_HS] = {"ti,otap-del-sel-sd-hs", MMC_CAP(SD_HS)},
- [UHS_SDR12] = {"ti,otap-del-sel-sdr12", MMC_CAP(UHS_SDR12)},
- [UHS_SDR25] = {"ti,otap-del-sel-sdr25", MMC_CAP(UHS_SDR25)},
- [UHS_SDR50] = {"ti,otap-del-sel-sdr50", MMC_CAP(UHS_SDR50)},
- [UHS_SDR104] = {"ti,otap-del-sel-sdr104", MMC_CAP(UHS_SDR104)},
- [UHS_DDR50] = {"ti,otap-del-sel-ddr50", MMC_CAP(UHS_DDR50)},
- [MMC_DDR_52] = {"ti,otap-del-sel-ddr52", MMC_CAP(MMC_DDR_52)},
- [MMC_HS_200] = {"ti,otap-del-sel-hs200", MMC_CAP(MMC_HS_200)},
- [MMC_HS_400] = {"ti,otap-del-sel-hs400", MMC_CAP(MMC_HS_400)},
+ [MMC_LEGACY] = {"ti,otap-del-sel-legacy",
+ "ti,itap-del-sel-legacy",
+ 0},
+ [MMC_HS] = {"ti,otap-del-sel-mmc-hs",
+ "ti,itap-del-sel-mms-hs",
+ MMC_CAP(MMC_HS)},
+ [SD_HS] = {"ti,otap-del-sel-sd-hs",
+ "ti,itap-del-sel-sd-hs",
+ MMC_CAP(SD_HS)},
+ [UHS_SDR12] = {"ti,otap-del-sel-sdr12",
+ "ti,itap-del-sel-sdr12",
+ MMC_CAP(UHS_SDR12)},
+ [UHS_SDR25] = {"ti,otap-del-sel-sdr25",
+ "ti,itap-del-sel-sdr25",
+ MMC_CAP(UHS_SDR25)},
+ [UHS_SDR50] = {"ti,otap-del-sel-sdr50",
+ NULL,
+ MMC_CAP(UHS_SDR50)},
+ [UHS_SDR104] = {"ti,otap-del-sel-sdr104",
+ NULL,
+ MMC_CAP(UHS_SDR104)},
+ [UHS_DDR50] = {"ti,otap-del-sel-ddr50",
+ NULL,
+ MMC_CAP(UHS_DDR50)},
+ [MMC_DDR_52] = {"ti,otap-del-sel-ddr52",
+ "ti,itap-del-sel-ddr52",
+ MMC_CAP(MMC_DDR_52)},
+ [MMC_HS_200] = {"ti,otap-del-sel-hs200",
+ NULL,
+ MMC_CAP(MMC_HS_200)},
+ [MMC_HS_400] = {"ti,otap-del-sel-hs400",
+ NULL,
+ MMC_CAP(MMC_HS_400)},
};
struct am654_driver_data {
@@ -127,12 +162,99 @@ static void am654_sdhci_set_control_reg(struct sdhci_host *host)
sdhci_set_uhs_timing(host);
}
+static int am654_sdhci_setup_dll(struct am654_sdhci_plat *plat,
+ unsigned int speed)
+{
+ int sel50, sel100, freqsel;
+ u32 mask, val;
+ int ret;
+
+ /* Disable delay chain mode */
+ regmap_update_bits(plat->base, PHY_CTRL5,
+ SELDLYTXCLK_MASK | SELDLYRXCLK_MASK, 0);
+
+ if (plat->flags & FREQSEL_2_BIT) {
+ switch (speed) {
+ case 200000000:
+ sel50 = 0;
+ sel100 = 0;
+ break;
+ case 100000000:
+ sel50 = 0;
+ sel100 = 1;
+ break;
+ default:
+ sel50 = 1;
+ sel100 = 0;
+ }
+
+ /* Configure PHY DLL frequency */
+ mask = SEL50_MASK | SEL100_MASK;
+ val = (sel50 << SEL50_SHIFT) | (sel100 << SEL100_SHIFT);
+ regmap_update_bits(plat->base, PHY_CTRL5, mask, val);
+ } else {
+ switch (speed) {
+ case 200000000:
+ freqsel = 0x0;
+ break;
+ default:
+ freqsel = 0x4;
+ }
+ regmap_update_bits(plat->base, PHY_CTRL5, FREQSEL_MASK,
+ freqsel << FREQSEL_SHIFT);
+ }
+
+ /* Configure DLL TRIM */
+ mask = DLL_TRIM_ICP_MASK;
+ val = plat->trm_icp << DLL_TRIM_ICP_SHIFT;
+
+ /* Configure DLL driver strength */
+ mask |= DR_TY_MASK;
+ val |= plat->drv_strength << DR_TY_SHIFT;
+ regmap_update_bits(plat->base, PHY_CTRL1, mask, val);
+
+ /* Enable DLL */
+ regmap_update_bits(plat->base, PHY_CTRL1, ENDLL_MASK,
+ 0x1 << ENDLL_SHIFT);
+ /*
+ * Poll for DLL ready. Use a one second timeout.
+ * Works in all experiments done so far
+ */
+ ret = regmap_read_poll_timeout(plat->base, PHY_STAT1, val,
+ val & DLLRDY_MASK, 1000, 1000000);
+
+ return ret;
+}
+
+static void am654_sdhci_write_itapdly(struct am654_sdhci_plat *plat,
+ u32 itapdly)
+{
+ /* Set ITAPCHGWIN before writing to ITAPDLY */
+ regmap_update_bits(plat->base, PHY_CTRL4, ITAPCHGWIN_MASK,
+ 1 << ITAPCHGWIN_SHIFT);
+ regmap_update_bits(plat->base, PHY_CTRL4, ITAPDLYSEL_MASK,
+ itapdly << ITAPDLYSEL_SHIFT);
+ regmap_update_bits(plat->base, PHY_CTRL4, ITAPCHGWIN_MASK, 0);
+}
+
+static void am654_sdhci_setup_delay_chain(struct am654_sdhci_plat *plat,
+ int mode)
+{
+ u32 mask, val;
+
+ val = 1 << SELDLYTXCLK_SHIFT | 1 << SELDLYRXCLK_SHIFT;
+ mask = SELDLYTXCLK_MASK | SELDLYRXCLK_MASK;
+ regmap_update_bits(plat->base, PHY_CTRL5, mask, val);
+
+ am654_sdhci_write_itapdly(plat, plat->itap_del_sel[mode]);
+}
+
static int am654_sdhci_set_ios_post(struct sdhci_host *host)
{
struct udevice *dev = host->mmc->dev;
struct am654_sdhci_plat *plat = dev_get_plat(dev);
unsigned int speed = host->mmc->clock;
- int sel50, sel100, freqsel;
+ int mode = host->mmc->selected_mode;
u32 otap_del_sel;
u32 mask, val;
int ret;
@@ -148,75 +270,29 @@ static int am654_sdhci_set_ios_post(struct sdhci_host *host)
sdhci_set_clock(host->mmc, speed);
/* switch phy back on */
- if (speed > AM654_SDHCI_MIN_FREQ) {
- otap_del_sel = plat->otap_del_sel[host->mmc->selected_mode];
- mask = OTAPDLYENA_MASK | OTAPDLYSEL_MASK;
- val = (1 << OTAPDLYENA_SHIFT) |
- (otap_del_sel << OTAPDLYSEL_SHIFT);
-
- /* Write to STRBSEL for HS400 speed mode */
- if (host->mmc->selected_mode == MMC_HS_400) {
- if (plat->flags & STRBSEL_4_BIT)
- mask |= STRBSEL_4BIT_MASK;
- else
- mask |= STRBSEL_8BIT_MASK;
-
- val |= plat->strb_sel << STRBSEL_SHIFT;
- }
+ otap_del_sel = plat->otap_del_sel[mode];
+ mask = OTAPDLYENA_MASK | OTAPDLYSEL_MASK;
+ val = (1 << OTAPDLYENA_SHIFT) |
+ (otap_del_sel << OTAPDLYSEL_SHIFT);
- regmap_update_bits(plat->base, PHY_CTRL4, mask, val);
-
- if (plat->flags & FREQSEL_2_BIT) {
- switch (speed) {
- case 200000000:
- sel50 = 0;
- sel100 = 0;
- break;
- case 100000000:
- sel50 = 0;
- sel100 = 1;
- break;
- default:
- sel50 = 1;
- sel100 = 0;
- }
-
- /* Configure PHY DLL frequency */
- mask = SEL50_MASK | SEL100_MASK;
- val = (sel50 << SEL50_SHIFT) | (sel100 << SEL100_SHIFT);
- regmap_update_bits(plat->base, PHY_CTRL5, mask, val);
- } else {
- switch (speed) {
- case 200000000:
- freqsel = 0x0;
- break;
- default:
- freqsel = 0x4;
- }
- regmap_update_bits(plat->base, PHY_CTRL5, FREQSEL_MASK,
- freqsel << FREQSEL_SHIFT);
- }
+ /* Write to STRBSEL for HS400 speed mode */
+ if (host->mmc->selected_mode == MMC_HS_400) {
+ if (plat->flags & STRBSEL_4_BIT)
+ mask |= STRBSEL_4BIT_MASK;
+ else
+ mask |= STRBSEL_8BIT_MASK;
- /* Configure DLL TRIM */
- mask = DLL_TRIM_ICP_MASK;
- val = plat->trm_icp << DLL_TRIM_ICP_SHIFT;
-
- /* Configure DLL driver strength */
- mask |= DR_TY_MASK;
- val |= plat->drv_strength << DR_TY_SHIFT;
- regmap_update_bits(plat->base, PHY_CTRL1, mask, val);
-
- /* Enable DLL */
- regmap_update_bits(plat->base, PHY_CTRL1, ENDLL_MASK,
- 0x1 << ENDLL_SHIFT);
- /*
- * Poll for DLL ready. Use a one second timeout.
- * Works in all experiments done so far
- */
- ret = regmap_read_poll_timeout(plat->base, PHY_STAT1, val,
- val & DLLRDY_MASK, 1000, 1000000);
+ val |= plat->strb_sel << STRBSEL_SHIFT;
+ }
+
+ regmap_update_bits(plat->base, PHY_CTRL4, mask, val);
+
+ if (mode > UHS_SDR25 && speed >= CLOCK_TOO_SLOW_HZ) {
+ ret = am654_sdhci_setup_dll(plat, speed);
if (ret)
return ret;
+ } else {
+ am654_sdhci_setup_delay_chain(plat, mode);
}
return 0;
@@ -354,15 +430,20 @@ static int sdhci_am654_get_otap_delay(struct udevice *dev,
* value is not found
*/
for (i = MMC_HS; i <= MMC_HS_400; i++) {
- ret = dev_read_u32(dev, td[i].binding, &plat->otap_del_sel[i]);
+ ret = dev_read_u32(dev, td[i].otap_binding,
+ &plat->otap_del_sel[i]);
if (ret) {
- dev_dbg(dev, "Couldn't find %s\n", td[i].binding);
+ dev_dbg(dev, "Couldn't find %s\n", td[i].otap_binding);
/*
* Remove the corresponding capability
* if an otap-del-sel value is not found
*/
cfg->host_caps &= ~td[i].capability;
}
+
+ if (td[i].itap_binding)
+ dev_read_u32(dev, td[i].itap_binding,
+ &plat->itap_del_sel[i]);
}
return 0;
--
2.17.1
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