tg3: Invert nvram_read() and nvram_read_swab()

This patch removes the blind byteswap of NVRAM data as it is read in.
To preserve the logic at the call sites, this patch also inverts every
call to tg3_nvram_read() and tg3_nvram_read_swab().  The call swap gets
confusing within tg3_nvram_read_le() (LE is a misnomer), but the reader
should be able to convince himself / herself that the resulting behavior
is still unchanged.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 28 insertions, 22 deletions

diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index d32b3efb2175..a2ca6ab2df00 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -2245,6 +2245,12 @@ static u32 tg3_nvram_logical_addr(struct tg3 *tp, u32 addr)
         return addr;
 }
 
+/* NOTE: Data read in from NVRAM is byteswapped according to
+ * the byteswapping settings for all other register accesses.
+ * tg3 devices are BE devices, so on a BE machine, the data
+ * returned will be exactly as it is seen in NVRAM.  On a LE
+ * machine, the 32-bit value will be byteswapped.
+ */
 static int tg3_nvram_read(struct tg3 *tp, u32 offset, u32 *val)
 {
         int ret;
@@ -2268,7 +2274,7 @@ static int tg3_nvram_read(struct tg3 *tp, u32 offset, u32 *val)
                 NVRAM_CMD_FIRST | NVRAM_CMD_LAST | NVRAM_CMD_DONE);
 
         if (ret == 0)
-                *val = swab32(tr32(NVRAM_RDDATA));
+                *val = tr32(NVRAM_RDDATA);
 
         tg3_disable_nvram_access(tp);
 
@@ -2290,7 +2296,7 @@ static int tg3_nvram_read_swab(struct tg3 *tp, u32 offset, u32 *val)
 static int tg3_nvram_read_le(struct tg3 *tp, u32 offset, __le32 *val)
 {
         u32 v;
-        int res = tg3_nvram_read(tp, offset, &v);
+        int res = tg3_nvram_read_swab(tp, offset, &v);
         if (!res)
                 *val = cpu_to_le32(v);
         return res;
@@ -9197,7 +9203,7 @@ static int tg3_test_nvram(struct tg3 *tp)
         __le32 *buf;
         int i, j, k, err = 0, size;
 
-        if (tg3_nvram_read_swab(tp, 0, &magic) != 0)
+        if (tg3_nvram_read(tp, 0, &magic) != 0)
                 return -EIO;
 
         if (magic == TG3_EEPROM_MAGIC)
@@ -10146,7 +10152,7 @@ static void __devinit tg3_get_eeprom_size(struct tg3 *tp)
 
         tp->nvram_size = EEPROM_CHIP_SIZE;
 
-        if (tg3_nvram_read_swab(tp, 0, &magic) != 0)
+        if (tg3_nvram_read(tp, 0, &magic) != 0)
                 return;
 
         if ((magic != TG3_EEPROM_MAGIC) &&
@@ -10162,7 +10168,7 @@ static void __devinit tg3_get_eeprom_size(struct tg3 *tp)
         cursize = 0x10;
 
         while (cursize < tp->nvram_size) {
-                if (tg3_nvram_read_swab(tp, cursize, &val) != 0)
+                if (tg3_nvram_read(tp, cursize, &val) != 0)
                         return;
 
                 if (val == magic)
@@ -10178,7 +10184,7 @@ static void __devinit tg3_get_nvram_size(struct tg3 *tp)
 {
         u32 val;
 
-        if (tg3_nvram_read_swab(tp, 0, &val) != 0)
+        if (tg3_nvram_read(tp, 0, &val) != 0)
                 return;
 
         /* Selfboot format */
@@ -10187,7 +10193,7 @@ static void __devinit tg3_get_nvram_size(struct tg3 *tp)
                 return;
         }
 
-        if (tg3_nvram_read(tp, 0xf0, &val) == 0) {
+        if (tg3_nvram_read_swab(tp, 0xf0, &val) == 0) {
                 if (val != 0) {
                         tp->nvram_size = (val >> 16) * 1024;
                         return;
@@ -11342,14 +11348,14 @@ static void __devinit tg3_read_partno(struct tg3 *tp)
         unsigned int i;
         u32 magic;
 
-        if (tg3_nvram_read_swab(tp, 0x0, &magic))
+        if (tg3_nvram_read(tp, 0x0, &magic))
                 goto out_not_found;
 
         if (magic == TG3_EEPROM_MAGIC) {
                 for (i = 0; i < 256; i += 4) {
                         u32 tmp;
 
-                        if (tg3_nvram_read(tp, 0x100 + i, &tmp))
+                        if (tg3_nvram_read_swab(tp, 0x100 + i, &tmp))
                                 goto out_not_found;
 
                         vpd_data[i + 0] = ((tmp >>  0) & 0xff);
@@ -11441,9 +11447,9 @@ static int __devinit tg3_fw_img_is_valid(struct tg3 *tp, u32 offset)
 {
         u32 val;
 
-        if (tg3_nvram_read_swab(tp, offset, &val) ||
+        if (tg3_nvram_read(tp, offset, &val) ||
             (val & 0xfc000000) != 0x0c000000 ||
-            tg3_nvram_read_swab(tp, offset + 4, &val) ||
+            tg3_nvram_read(tp, offset + 4, &val) ||
             val != 0)
                 return 0;
 
@@ -11475,7 +11481,7 @@ static void __devinit tg3_read_sb_ver(struct tg3 *tp, u32 val)
                 return;
         }
 
-        if (tg3_nvram_read_swab(tp, offset, &val))
+        if (tg3_nvram_read(tp, offset, &val))
                 return;
 
         build = (val & TG3_EEPROM_SB_EDH_BLD_MASK) >>
@@ -11501,7 +11507,7 @@ static void __devinit tg3_read_fw_ver(struct tg3 *tp)
         u32 ver_offset;
         int i, bcnt;
 
-        if (tg3_nvram_read_swab(tp, 0, &val))
+        if (tg3_nvram_read(tp, 0, &val))
                 return;
 
         if (val != TG3_EEPROM_MAGIC) {
@@ -11511,14 +11517,14 @@ static void __devinit tg3_read_fw_ver(struct tg3 *tp)
                 return;
         }
 
-        if (tg3_nvram_read_swab(tp, 0xc, &offset) ||
-            tg3_nvram_read_swab(tp, 0x4, &start))
+        if (tg3_nvram_read(tp, 0xc, &offset) ||
+            tg3_nvram_read(tp, 0x4, &start))
                 return;
 
         offset = tg3_nvram_logical_addr(tp, offset);
 
         if (!tg3_fw_img_is_valid(tp, offset) ||
-            tg3_nvram_read_swab(tp, offset + 8, &ver_offset))
+            tg3_nvram_read(tp, offset + 8, &ver_offset))
                 return;
 
         offset = offset + ver_offset - start;
@@ -11537,7 +11543,7 @@ static void __devinit tg3_read_fw_ver(struct tg3 *tp)
         for (offset = TG3_NVM_DIR_START;
              offset < TG3_NVM_DIR_END;
              offset += TG3_NVM_DIRENT_SIZE) {
-                if (tg3_nvram_read_swab(tp, offset, &val))
+                if (tg3_nvram_read(tp, offset, &val))
                         return;
 
                 if ((val >> TG3_NVM_DIRTYPE_SHIFT) == TG3_NVM_DIRTYPE_ASFINI)
@@ -11549,12 +11555,12 @@ static void __devinit tg3_read_fw_ver(struct tg3 *tp)
 
         if (!(tp->tg3_flags2 & TG3_FLG2_5705_PLUS))
                 start = 0x08000000;
-        else if (tg3_nvram_read_swab(tp, offset - 4, &start))
+        else if (tg3_nvram_read(tp, offset - 4, &start))
                 return;
 
-        if (tg3_nvram_read_swab(tp, offset + 4, &offset) ||
+        if (tg3_nvram_read(tp, offset + 4, &offset) ||
             !tg3_fw_img_is_valid(tp, offset) ||
-            tg3_nvram_read_swab(tp, offset + 8, &val))
+            tg3_nvram_read(tp, offset + 8, &val))
                 return;
 
         offset += val - start;
@@ -12349,8 +12355,8 @@ static int __devinit tg3_get_device_address(struct tg3 *tp)
         }
         if (!addr_ok) {
                 /* Next, try NVRAM. */
-                if (!tg3_nvram_read(tp, mac_offset + 0, &hi) &&
-                    !tg3_nvram_read(tp, mac_offset + 4, &lo)) {
+                if (!tg3_nvram_read_swab(tp, mac_offset + 0, &hi) &&
+                    !tg3_nvram_read_swab(tp, mac_offset + 4, &lo)) {
                         dev->dev_addr[0] = ((hi >> 16) & 0xff);
                         dev->dev_addr[1] = ((hi >> 24) & 0xff);
                         dev->dev_addr[2] = ((lo >>  0) & 0xff);