sdhci: add i.MX SD Stable Clock bit

Add the ESDHC PRSSTAT_SDSTB bit, using the value of SDHC_CLOCK_INT_STABLE. Freescale recommends checking this bit when changing clock frequency. Signed-off-by: Hans-Erik Floryd <hans-erik.floryd@rt-labs.com> Message-id: 1534507843-4251-1-git-send-email-hans-erik.floryd@rt-labs.com [PMM: fixed indentation] Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
qemu · Aug 20, 2018 · 6bfd06d · 6bfd06d
1 parent 22907d2
commit 6bfd06d
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diff --git a/hw/sd/sdhci-internal.h b/hw/sd/sdhci-internal.h
@@ -302,4 +302,6 @@ extern const VMStateDescription sdhci_vmstate;
 #define ESDHC_CTRL_4BITBUS              (0x1 << 1)
 #define ESDHC_CTRL_8BITBUS              (0x2 << 1)
 
+#define ESDHC_PRNSTS_SDSTB              (1 << 3)
+
 #endif
diff --git a/hw/sd/sdhci.c b/hw/sd/sdhci.c
@@ -1651,6 +1651,14 @@ static uint64_t usdhc_read(void *opaque, hwaddr offset, unsigned size)
 
         break;
 
+    case SDHC_PRNSTS:
+        /* Add SDSTB (SD Clock Stable) bit to PRNSTS */
+        ret = sdhci_read(opaque, offset, size) & ~ESDHC_PRNSTS_SDSTB;
+        if (s->clkcon & SDHC_CLOCK_INT_STABLE) {
+            ret |= ESDHC_PRNSTS_SDSTB;
+        }
+        break;
+
     case ESDHC_DLL_CTRL:
     case ESDHC_TUNE_CTRL_STATUS:
     case ESDHC_UNDOCUMENTED_REG27: