[SCSI] qla4xxx: fix for timing issue for nvram accesses.

This patch fixes a timing issue related to nvram accesses in qla4xxx
driver for some cpu/slot speed combination.

Signed-off-by: David Somayajulu <david.somayajulu@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 36 insertions, 28 deletions

diff --git a/drivers/scsi/qla4xxx/ql4_nvram.c b/drivers/scsi/qla4xxx/ql4_nvram.c
index fc5020395407..58afd135aa1d 100644
--- a/drivers/scsi/qla4xxx/ql4_nvram.c
+++ b/drivers/scsi/qla4xxx/ql4_nvram.c
@@ -7,6 +7,13 @@
 
 #include "ql4_def.h"
 
+static inline void eeprom_cmd(uint32_t cmd, struct scsi_qla_host *ha)
+{
+        writel(cmd, isp_nvram(ha));
+        readl(isp_nvram(ha));
+        udelay(1);
+}
+
 static inline int eeprom_size(struct scsi_qla_host *ha)
 {
         return is_qla4010(ha) ? FM93C66A_SIZE_16 : FM93C86A_SIZE_16;
@@ -28,8 +35,7 @@ static int fm93c56a_select(struct scsi_qla_host * ha)
         DEBUG5(printk(KERN_ERR "fm93c56a_select:\n"));
 
         ha->eeprom_cmd_data = AUBURN_EEPROM_CS_1 | 0x000f0000;
-        writel(ha->eeprom_cmd_data, isp_nvram(ha));
-        readl(isp_nvram(ha));
+        eeprom_cmd(ha->eeprom_cmd_data, ha);
         return 1;
 }
 
@@ -41,12 +47,13 @@ static int fm93c56a_cmd(struct scsi_qla_host * ha, int cmd, int addr)
         int previousBit;
 
         /* Clock in a zero, then do the start bit. */
-        writel(ha->eeprom_cmd_data | AUBURN_EEPROM_DO_1, isp_nvram(ha));
-        writel(ha->eeprom_cmd_data | AUBURN_EEPROM_DO_1 |
-               AUBURN_EEPROM_CLK_RISE, isp_nvram(ha));
-        writel(ha->eeprom_cmd_data | AUBURN_EEPROM_DO_1 |
-               AUBURN_EEPROM_CLK_FALL, isp_nvram(ha));
-        readl(isp_nvram(ha));
+        eeprom_cmd(ha->eeprom_cmd_data | AUBURN_EEPROM_DO_1, ha);
+
+        eeprom_cmd(ha->eeprom_cmd_data | AUBURN_EEPROM_DO_1 |
+               AUBURN_EEPROM_CLK_RISE, ha);
+        eeprom_cmd(ha->eeprom_cmd_data | AUBURN_EEPROM_DO_1 |
+               AUBURN_EEPROM_CLK_FALL, ha);
+
         mask = 1 << (FM93C56A_CMD_BITS - 1);
 
         /* Force the previous data bit to be different. */
@@ -60,14 +67,14 @@ static int fm93c56a_cmd(struct scsi_qla_host * ha, int cmd, int addr)
                          * If the bit changed, then change the DO state to
                          * match.
                          */
-                        writel(ha->eeprom_cmd_data | dataBit, isp_nvram(ha));
+                        eeprom_cmd(ha->eeprom_cmd_data | dataBit, ha);
                         previousBit = dataBit;
                 }
-                writel(ha->eeprom_cmd_data | dataBit |
-                       AUBURN_EEPROM_CLK_RISE, isp_nvram(ha));
-                writel(ha->eeprom_cmd_data | dataBit |
-                       AUBURN_EEPROM_CLK_FALL, isp_nvram(ha));
-                readl(isp_nvram(ha));
+                eeprom_cmd(ha->eeprom_cmd_data | dataBit |
+                       AUBURN_EEPROM_CLK_RISE, ha);
+                eeprom_cmd(ha->eeprom_cmd_data | dataBit |
+                       AUBURN_EEPROM_CLK_FALL, ha);
+
                 cmd = cmd << 1;
         }
         mask = 1 << (eeprom_no_addr_bits(ha) - 1);
@@ -82,14 +89,15 @@ static int fm93c56a_cmd(struct scsi_qla_host * ha, int cmd, int addr)
                          * If the bit changed, then change the DO state to
                          * match.
                          */
-                        writel(ha->eeprom_cmd_data | dataBit, isp_nvram(ha));
+                        eeprom_cmd(ha->eeprom_cmd_data | dataBit, ha);
+
                         previousBit = dataBit;
                 }
-                writel(ha->eeprom_cmd_data | dataBit |
-                       AUBURN_EEPROM_CLK_RISE, isp_nvram(ha));
-                writel(ha->eeprom_cmd_data | dataBit |
-                       AUBURN_EEPROM_CLK_FALL, isp_nvram(ha));
-                readl(isp_nvram(ha));
+                eeprom_cmd(ha->eeprom_cmd_data | dataBit |
+                       AUBURN_EEPROM_CLK_RISE, ha);
+                eeprom_cmd(ha->eeprom_cmd_data | dataBit |
+                       AUBURN_EEPROM_CLK_FALL, ha);
+
                 addr = addr << 1;
         }
         return 1;
@@ -98,8 +106,7 @@ static int fm93c56a_cmd(struct scsi_qla_host * ha, int cmd, int addr)
 static int fm93c56a_deselect(struct scsi_qla_host * ha)
 {
         ha->eeprom_cmd_data = AUBURN_EEPROM_CS_0 | 0x000f0000;
-        writel(ha->eeprom_cmd_data, isp_nvram(ha));
-        readl(isp_nvram(ha));
+        eeprom_cmd(ha->eeprom_cmd_data, ha);
         return 1;
 }
 
@@ -112,12 +119,13 @@ static int fm93c56a_datain(struct scsi_qla_host * ha, unsigned short *value)
         /* Read the data bits
          * The first bit is a dummy.  Clock right over it. */
         for (i = 0; i < eeprom_no_data_bits(ha); i++) {
-                writel(ha->eeprom_cmd_data |
-                       AUBURN_EEPROM_CLK_RISE, isp_nvram(ha));
-                writel(ha->eeprom_cmd_data |
-                       AUBURN_EEPROM_CLK_FALL, isp_nvram(ha));
-                dataBit =
-                        (readw(isp_nvram(ha)) & AUBURN_EEPROM_DI_1) ? 1 : 0;
+                eeprom_cmd(ha->eeprom_cmd_data |
+                       AUBURN_EEPROM_CLK_RISE, ha);
+                eeprom_cmd(ha->eeprom_cmd_data |
+                       AUBURN_EEPROM_CLK_FALL, ha);
+
+                dataBit = (readw(isp_nvram(ha)) & AUBURN_EEPROM_DI_1) ? 1 : 0;
+
                 data = (data << 1) | dataBit;
         }