mvsata_ide: adjust port init sequence

mvsata_ide_initialize_port(): adjust init sequence (SStatus
should be checked only after all writes to SControl) and
return success/failure to ide_preinit().

Also, as some tests showed init durations in the hundreds
of us, raise the time-out to 01 ms to be on the safe side.

Signed-off-by: Albert Aribaud <albert.aribaud@free.fr>

diff --git a/drivers/block/mvsata_ide.c b/drivers/block/mvsata_ide.c
index 077b2789bb3c8d99df6c4a8e0b561434a6f5bb0b..3d6993ac2af21643fd96e5191943afd33f19620d 100644 (file)
--- a/drivers/block/mvsata_ide.c
+++ b/drivers/block/mvsata_ide.c
@@ -90,6 +90,18 @@ struct mvsata_port_registers {
 #define MVSATA_SSTATUS_DET_MASK                        0x0000000F
 #define MVSATA_SSTATUS_DET_DEVCOMM             0x00000003
 
+/*
+ * Status codes to return to client callers. Currently, callers ignore
+ * exact value and only care for zero or nonzero, so no need to make this
+ * public, it is only #define'd for clarity.
+ * If/when standard negative codes are implemented in U-boot, then these
+ * #defines should be moved to, or replaced by ones from, the common list
+ * of status codes.
+ */
+
+#define MVSATA_STATUS_OK       0
+#define MVSATA_STATUS_TIMEOUT  -1
+
 /*
  * Initialize one MVSATAHC port: set SControl's IPM to "always active"
  * and DET to "reset", then wait for SStatus's DET to become "device and
@@ -97,23 +109,30 @@ struct mvsata_port_registers {
  * DET back to "no action".
  */
 
-static void mvsata_ide_initialize_port(struct mvsata_port_registers *port)
+static int mvsata_ide_initialize_port(struct mvsata_port_registers *port)
 {
        u32 control;
        u32 status;
-       u32 tout = 50; /* wait at most 50 us for SATA reset to complete */
+       u32 timeleft = 10000; /* wait at most 10 ms for SATA reset to complete */
 
+       /* Set control IPM to 3 (no low power) and DET to 1 (initialize) */
        control = readl(&port->scontrol);
        control = (control & ~MVSATA_SCONTROL_MASK) | MVSATA_PORT_INIT;
        writel(control, &port->scontrol);
-       while (--tout) {
+       /* Toggle control DET back to 0 (normal operation) */
+       control = (control & ~MVSATA_SCONTROL_MASK) | MVSATA_PORT_USE;
+       writel(control, &port->scontrol);
+       /* wait for status DET to become 3 (device and communication OK) */
+       while (--timeleft) {
                status = readl(&port->sstatus) & MVSATA_SSTATUS_DET_MASK;
                if (status == MVSATA_SSTATUS_DET_DEVCOMM)
                        break;
                udelay(1);
        }
-       control = (control & ~MVSATA_SCONTROL_MASK) | MVSATA_PORT_USE;
-       writel(control, &port->scontrol);
+       /* return success or time-out error depending on time left */
+       if (!timeleft)
+               return MVSATA_STATUS_TIMEOUT;
+       return MVSATA_STATUS_OK;
 }
 
 /*
@@ -123,18 +142,23 @@ static void mvsata_ide_initialize_port(struct mvsata_port_registers *port)
 
 int ide_preinit(void)
 {
+       int status;
        /* Enable ATA port 0 (could be SATA port 0 or 1) if declared */
 #if defined(CONFIG_SYS_ATA_IDE0_OFFSET)
-       mvsata_ide_initialize_port(
+       status = mvsata_ide_initialize_port(
                (struct mvsata_port_registers *)
                (CONFIG_SYS_ATA_BASE_ADDR + CONFIG_SYS_ATA_IDE0_OFFSET));
+       if (status)
+               return status;
 #endif
        /* Enable ATA port 1 (could be SATA port 0 or 1) if declared */
 #if defined(CONFIG_SYS_ATA_IDE1_OFFSET)
-       mvsata_ide_initialize_port(
+       status = mvsata_ide_initialize_port(
                (struct mvsata_port_registers *)
                (CONFIG_SYS_ATA_BASE_ADDR + CONFIG_SYS_ATA_IDE1_OFFSET));
+       if (status)
+               return status;
 #endif
-       /* return 0 as we always succeed */
-       return 0;
+       /* return success if all ports initializations succeeded */
+       return MVSATA_STATUS_OK;
 }