[PATCH 3/6] mmc: zynq_sdhci: Use Mask writes for Tap delays
Ashok Reddy Soma
ashok.reddy.soma at xilinx.com
Fri Jul 9 09:17:13 CEST 2021
Restrict tap_delay value to the allowed size(8bits for itap and 6 bits
for otap) before writing to the tap delay register.
Clear ITAP and OTAP delay bits before updating with the new tap value
for Versal platform.
Signed-off-by: Ashok Reddy Soma <ashok.reddy.soma at xilinx.com>
---
drivers/mmc/zynq_sdhci.c | 58 +++++++++++++++++++++-------------------
1 file changed, 31 insertions(+), 27 deletions(-)
diff --git a/drivers/mmc/zynq_sdhci.c b/drivers/mmc/zynq_sdhci.c
index 4f014da7ea..c600d97f1e 100644
--- a/drivers/mmc/zynq_sdhci.c
+++ b/drivers/mmc/zynq_sdhci.c
@@ -19,11 +19,13 @@
#include <sdhci.h>
#include <zynqmp_tap_delay.h>
-#define SDHCI_ARASAN_ITAPDLY_REGISTER 0xF0F8
-#define SDHCI_ARASAN_OTAPDLY_REGISTER 0xF0FC
-#define SDHCI_ITAPDLY_CHGWIN 0x200
-#define SDHCI_ITAPDLY_ENABLE 0x100
-#define SDHCI_OTAPDLY_ENABLE 0x40
+#define SDHCI_ARASAN_ITAPDLY_REGISTER 0xF0F8
+#define SDHCI_ARASAN_ITAPDLY_SEL_MASK 0xFF
+#define SDHCI_ARASAN_OTAPDLY_REGISTER 0xF0FC
+#define SDHCI_ARASAN_OTAPDLY_SEL_MASK 0x3F
+#define SDHCI_ITAPDLY_CHGWIN 0x200
+#define SDHCI_ITAPDLY_ENABLE 0x100
+#define SDHCI_OTAPDLY_ENABLE 0x40
#define SDHCI_TUNING_LOOP_COUNT 40
#define MMC_BANK2 0x2
@@ -297,6 +299,7 @@ static int sdhci_versal_sdcardclk_set_phase(struct sdhci_host *host,
struct mmc *mmc = (struct mmc *)host->mmc;
u8 tap_delay, tap_max = 0;
int timing = mode2timing[mmc->selected_mode];
+ u32 regval;
/*
* This is applicable for SDHCI_SPEC_300 and above
@@ -329,16 +332,16 @@ static int sdhci_versal_sdcardclk_set_phase(struct sdhci_host *host,
tap_delay = (degrees * tap_max) / 360;
+ /* Limit output tap_delay value to 6 bits */
+ tap_delay &= SDHCI_ARASAN_OTAPDLY_SEL_MASK;
+
/* Set the Clock Phase */
- if (tap_delay) {
- u32 regval;
-
- regval = sdhci_readl(host, SDHCI_ARASAN_OTAPDLY_REGISTER);
- regval |= SDHCI_OTAPDLY_ENABLE;
- sdhci_writel(host, regval, SDHCI_ARASAN_OTAPDLY_REGISTER);
- regval |= tap_delay;
- sdhci_writel(host, regval, SDHCI_ARASAN_OTAPDLY_REGISTER);
- }
+ regval = sdhci_readl(host, SDHCI_ARASAN_OTAPDLY_REGISTER);
+ regval |= SDHCI_OTAPDLY_ENABLE;
+ sdhci_writel(host, regval, SDHCI_ARASAN_OTAPDLY_REGISTER);
+ regval &= ~SDHCI_ARASAN_OTAPDLY_SEL_MASK;
+ regval |= tap_delay;
+ sdhci_writel(host, regval, SDHCI_ARASAN_OTAPDLY_REGISTER);
return 0;
}
@@ -358,6 +361,7 @@ static int sdhci_versal_sampleclk_set_phase(struct sdhci_host *host,
struct mmc *mmc = (struct mmc *)host->mmc;
u8 tap_delay, tap_max = 0;
int timing = mode2timing[mmc->selected_mode];
+ u32 regval;
/*
* This is applicable for SDHCI_SPEC_300 and above
@@ -390,20 +394,20 @@ static int sdhci_versal_sampleclk_set_phase(struct sdhci_host *host,
tap_delay = (degrees * tap_max) / 360;
+ /* Limit input tap_delay value to 8 bits */
+ tap_delay &= SDHCI_ARASAN_ITAPDLY_SEL_MASK;
+
/* Set the Clock Phase */
- if (tap_delay) {
- u32 regval;
-
- regval = sdhci_readl(host, SDHCI_ARASAN_ITAPDLY_REGISTER);
- regval |= SDHCI_ITAPDLY_CHGWIN;
- sdhci_writel(host, regval, SDHCI_ARASAN_ITAPDLY_REGISTER);
- regval |= SDHCI_ITAPDLY_ENABLE;
- sdhci_writel(host, regval, SDHCI_ARASAN_ITAPDLY_REGISTER);
- regval |= tap_delay;
- sdhci_writel(host, regval, SDHCI_ARASAN_ITAPDLY_REGISTER);
- regval &= ~SDHCI_ITAPDLY_CHGWIN;
- sdhci_writel(host, regval, SDHCI_ARASAN_ITAPDLY_REGISTER);
- }
+ regval = sdhci_readl(host, SDHCI_ARASAN_ITAPDLY_REGISTER);
+ regval |= SDHCI_ITAPDLY_CHGWIN;
+ sdhci_writel(host, regval, SDHCI_ARASAN_ITAPDLY_REGISTER);
+ regval |= SDHCI_ITAPDLY_ENABLE;
+ sdhci_writel(host, regval, SDHCI_ARASAN_ITAPDLY_REGISTER);
+ regval &= ~SDHCI_ARASAN_ITAPDLY_SEL_MASK;
+ regval |= tap_delay;
+ sdhci_writel(host, regval, SDHCI_ARASAN_ITAPDLY_REGISTER);
+ regval &= ~SDHCI_ITAPDLY_CHGWIN;
+ sdhci_writel(host, regval, SDHCI_ARASAN_ITAPDLY_REGISTER);
return 0;
}
--
2.17.1
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