sfc: Reduce delays in SFE4001 initialisation

Currently the board initialisation includes 2 delays of 1 second each.
Usually it is unnecessary to wait that long, so check before doing so.

Correct some of the comments and log messages while we're here.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

diff --git a/drivers/net/sfc/sfe4001.c b/drivers/net/sfc/sfe4001.c
index b278495..f927281 100644 (file)
--- a/drivers/net/sfc/sfe4001.c
+++ b/drivers/net/sfc/sfe4001.c
@@ -145,7 +145,7 @@ MODULE_PARM_DESC(phy_flash_cfg,
 int sfe4001_init(struct efx_nic *efx)
 {
        struct i2c_client *hwmon_client, *ioexp_client;
-       unsigned int count;
+       unsigned int i, j;
        int rc;
        u8 out;
        efx_dword_t reg;
@@ -209,17 +209,24 @@ int sfe4001_init(struct efx_nic *efx)
        if (rc)
                goto fail_on;
 
-       /* Turn all power off then wait 1 sec. This ensures PHY is reset */
+       /* If PHY power is on, turn it all off and wait 1 second to
+        * ensure a full reset.
+        */
+       rc = i2c_smbus_read_byte_data(ioexp_client, P0_OUT);
+       if (rc < 0)
+               goto fail_on;
        out = 0xff & ~((0 << P0_EN_1V2_LBN) | (0 << P0_EN_2V5_LBN) |
                       (0 << P0_EN_3V3X_LBN) | (0 << P0_EN_5V_LBN) |
                       (0 << P0_EN_1V0X_LBN));
-       rc = i2c_smbus_write_byte_data(ioexp_client, P0_OUT, out);
-       if (rc)
-               goto fail_on;
+       if (rc != out) {
+               EFX_INFO(efx, "power-cycling PHY\n");
+               rc = i2c_smbus_write_byte_data(ioexp_client, P0_OUT, out);
+               if (rc)
+                       goto fail_on;
+               schedule_timeout_uninterruptible(HZ);
+       }
 
-       schedule_timeout_uninterruptible(HZ);
-       count = 0;
-       do {
+       for (i = 0; i < 20; ++i) {
                /* Turn on 1.2V, 2.5V, 3.3V and 5V power rails */
                out = 0xff & ~((1 << P0_EN_1V2_LBN) | (1 << P0_EN_2V5_LBN) |
                               (1 << P0_EN_3V3X_LBN) | (1 << P0_EN_5V_LBN) |
@@ -238,23 +245,29 @@ int sfe4001_init(struct efx_nic *efx)
                if (rc)
                        goto fail_on;
 
-               EFX_INFO(efx, "waiting for power (attempt %d)...\n", count);
-
-               schedule_timeout_uninterruptible(HZ);
-
-               /* Check DSP is powered */
-               rc = i2c_smbus_read_byte_data(ioexp_client, P1_IN);
-               if (rc < 0)
-                       goto fail_on;
-               if (rc & (1 << P1_AFE_PWD_LBN))
-                       goto done;
+               EFX_INFO(efx, "waiting for DSP boot (attempt %d)...\n", i);
 
-               /* DSP doesn't look powered in flash config mode */
-               if (sfe4001_phy_flash_cfg)
+               /* In flash config mode, DSP does not turn on AFE, so
+                * just wait 1 second.
+                */
+               if (sfe4001_phy_flash_cfg) {
+                       schedule_timeout_uninterruptible(HZ);
                        goto done;
-       } while (++count < 20);
+               }
+
+               for (j = 0; j < 10; ++j) {
+                       msleep(100);
+
+                       /* Check DSP has asserted AFE power line */
+                       rc = i2c_smbus_read_byte_data(ioexp_client, P1_IN);
+                       if (rc < 0)
+                               goto fail_on;
+                       if (rc & (1 << P1_AFE_PWD_LBN))
+                               goto done;
+               }
+       }
 
-       EFX_INFO(efx, "timed out waiting for power\n");
+       EFX_INFO(efx, "timed out waiting for DSP boot\n");
        rc = -ETIMEDOUT;
        goto fail_on;