mmc: sdhci: Add PLL Enable support to internal clock setup

The GL9750 and GL9755 chipsets, and possibly others, require PLL Enable
setup as part of the internal clock setup as described in 3.2.1 Internal
Clock Setup Sequence of SD Host Controller Simplified Specification
Version 4.20.

Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
Co-developed-by: Michael K Johnson <johnsonm@danlj.org>
Signed-off-by: Michael K Johnson <johnsonm@danlj.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 40de56d6da0bf9ba20f5da274bd8e639a43de632..de833b1eadb98b08bae3b807dac0f46160d7c2d9 100644 (file)
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1653,6 +1653,29 @@ void sdhci_enable_clk(struct sdhci_host *host, u16 clk)
                udelay(10);
        }
 
+       if (host->version >= SDHCI_SPEC_410 && host->v4_mode) {
+               clk |= SDHCI_CLOCK_PLL_EN;
+               clk &= ~SDHCI_CLOCK_INT_STABLE;
+               sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+               /* Wait max 150 ms */
+               timeout = ktime_add_ms(ktime_get(), 150);
+               while (1) {
+                       bool timedout = ktime_after(ktime_get(), timeout);
+
+                       clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+                       if (clk & SDHCI_CLOCK_INT_STABLE)
+                               break;
+                       if (timedout) {
+                               pr_err("%s: PLL clock never stabilised.\n",
+                                      mmc_hostname(host->mmc));
+                               sdhci_dumpregs(host);
+                               return;
+                       }
+                       udelay(10);
+               }
+       }
+
        clk |= SDHCI_CLOCK_CARD_EN;
        sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
 }

diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 902f855efe8f8b0aad28731b1040ad56c086f688..929310e869a3b27fdab6be3d0623d8abfe899b3c 100644 (file)
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -114,6 +114,7 @@
 #define  SDHCI_DIV_HI_MASK     0x300
 #define  SDHCI_PROG_CLOCK_MODE 0x0020
 #define  SDHCI_CLOCK_CARD_EN   0x0004
+#define  SDHCI_CLOCK_PLL_EN    0x0008
 #define  SDHCI_CLOCK_INT_STABLE        0x0002
 #define  SDHCI_CLOCK_INT_EN    0x0001