The eSDHC is not compatible with SD spec well, so we need
to use eSDHC-special code to switch to SDR50 mode.
1. IO signal voltage switching, eSDHC uses SDHC_VS to switch
io voltage and it's needed to configure a global utilities
register SCFG_SDHCIOVSELCR(if it has) and SDHC_VS signal.
2. Before executing tuning procedure, eSDHC should set its own
tuning block.
static const struct sdhci_ops sdhci_esdhc_ops = {
...
.set_tuning_block = esdhc_set_tuning_block,
.signal_voltage_switch = esdhc_signal_voltage_switch,
};
Signed-off-by: Yangbo Lu <yangbo.lu@xxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci-esdhc.h | 2 ++
drivers/mmc/host/sdhci-of-esdhc.c | 62 ++++++++++++++++++++++++++++++++++++++-
2 files changed, 63 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/host/sdhci-esdhc.h b/drivers/mmc/host/sdhci-esdhc.h
index de9be18..a04b8bb 100644
--- a/drivers/mmc/host/sdhci-esdhc.h
+++ b/drivers/mmc/host/sdhci-esdhc.h
@@ -26,6 +26,8 @@
#define ESDHCI_PRESENT_STATE 0x24
#define ESDHC_CLK_STABLE 0x00000008
+#define ESDHC_DLSL 0x0f000000
+#define ESDHC_CLSL 0x00800000
#define ESDHC_PROCTL 0x28
#define ESDHC_VOLT_SEL 0x00000400
diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-of-esdhc.c
index 5aabadf..c887b8e 100644
--- a/drivers/mmc/host/sdhci-of-esdhc.c
+++ b/drivers/mmc/host/sdhci-of-esdhc.c
@@ -19,6 +19,7 @@
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/mmc/host.h>
+#include <linux/of_address.h>
#include "sdhci-pltfm.h"
#include "sdhci-esdhc.h"
@@ -39,6 +40,17 @@ static u32 adapter_type;
static u32 esdhc_readl(struct sdhci_host *host, int reg)
{
u32 ret;
+ u32 clsl;
+ u32 dlsl;
+
+ if (reg == SDHCI_PRESENT_STATE) {
+ ret = in_be32(host->ioaddr + reg);
+ clsl = ret & ESDHC_CLSL;
+ dlsl = ret & ESDHC_DLSL;
+ ret &= ~((ESDHC_CLSL << 1) | (ESDHC_DLSL >> 4));
+ ret |= ((clsl << 1) | (dlsl >> 4));
+ return ret;
+ }
if (reg == SDHCI_CAPABILITIES_1) {
ret = in_be32(host->ioaddr + ESDHC_CAPABILITIES_1);
@@ -48,6 +60,15 @@ static u32 esdhc_readl(struct sdhci_host *host, int reg)
host->mmc->caps2 |= MMC_CAP2_HS200;
ret &= ~ESDHC_MODE_MASK;
break;
+ case ESDHC_ADAPTER_TYPE_2:
+ if (ret & ESDHC_MODE_MASK) {
+ ret &= ~ESDHC_MODE_MASK;
+ /* If it exists UHS-I support, enable SDR50 */
+ host->mmc->caps |= (MMC_CAP_UHS_SDR50 |
+ MMC_CAP_UHS_SDR25 |
+ MMC_CAP_UHS_SDR12);
+ }
+ break;
default:
ret &= ~ESDHC_MODE_MASK;
}
@@ -256,11 +277,14 @@ static void esdhc_of_set_clock(struct sdhci_host *host, unsigned int clock)
int pre_div = 1;
int div = 1;
u32 temp;
+ int timeout;
host->mmc->actual_clock = 0;
- if (clock == 0)
+ if (clock == 0) {
+ esdhc_clock_control(host, false);
return;
+ }
/* Workaround to start pre_div at 2 for VNN < VENDOR_V_23 */
temp = esdhc_readw(host, SDHCI_HOST_VERSION);
@@ -298,6 +322,22 @@ static void esdhc_of_set_clock(struct sdhci_host *host, unsigned int clock)
| (div << ESDHC_DIVIDER_SHIFT)
| (pre_div << ESDHC_PREDIV_SHIFT));
sdhci_writel(host, temp, ESDHC_SYSTEM_CONTROL);
+
+ /* Wait max 20 ms */
+ timeout = 20;
+ while (!(sdhci_readl(host, ESDHCI_PRESENT_STATE) & ESDHC_CLK_STABLE)) {
+ if (timeout == 0) {
+ pr_err("%s: Internal clock never stabilised.\n",
+ mmc_hostname(host->mmc));
+ return;
+ }
+ timeout--;
+ mdelay(1);
+ }
+
+ temp |= ESDHC_CLOCK_CRDEN;
+ sdhci_writel(host, temp, ESDHC_SYSTEM_CONTROL);
+
mdelay(1);
}
@@ -351,9 +391,17 @@ void esdhc_set_tuning_block(struct sdhci_host *host)
esdhc_clock_control(host, true);
}
+static const struct of_device_id scfg_device_ids[] = {
+ { .compatible = "fsl,t1040-scfg", },
+ {}
+};
+
void esdhc_signal_voltage_switch(struct sdhci_host *host,
unsigned char signal_voltage)
{
+ struct device_node *scfg_node;
+ void __iomem *scfg_base;
+ u32 scfg_sdhciovselcr;
u32 value;
value = sdhci_readl(host, ESDHC_PROCTL);
@@ -364,6 +412,18 @@ void esdhc_signal_voltage_switch(struct sdhci_host *host,
sdhci_writel(host, value, ESDHC_PROCTL);
break;
case MMC_SIGNAL_VOLTAGE_180:
+ scfg_node = of_find_matching_node(NULL, scfg_device_ids);
+ if (scfg_node) {
+ scfg_base = of_iomap(scfg_node, 0);
+ of_node_put(scfg_node);
+ if (scfg_base) {
+ scfg_sdhciovselcr = 0x408;
+ out_be32(scfg_base + scfg_sdhciovselcr,
+ 0x80000001);
+ iounmap(scfg_base);
+ }
+ }
+
value |= ESDHC_VOLT_SEL;
sdhci_writel(host, value, ESDHC_PROCTL);
break;
--
2.1.0.27.g96db324
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