Subject: [PATCH 06/14] tg3: Invert nvram_read() and nvram_read_swab()

From: "Matt Carlson" <[email-masked]>
Date: Wed, 25 Feb 2009 16:25:00 -0800

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 <[email-masked]>
Signed-off-by: Benjamin Li <[email-masked]>
Signed-off-by: Michael Chan <[email-masked]>
---
 drivers/net/tg3.c |   50 ++++++++++++++++++++++++++++----------------------
 1 files changed, 28 insertions(+), 22 deletions(-)

diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index d32b3ef..a2ca6ab 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);
-- 
1.6.0.6