tg3: Eliminate tg3_nvram_read_swab()
The remaining uses of tg3_nvram_read_swab() either intended to read the
data from NVRAM exactly as tg3_nvram_read_be32() did or hide deeper
interpretations of the data. For the former case, a direct replacement
of tg3_nvram_read_swab() with tg3_nvram_read_be32() is in order. For
the latter case, we remove tg3_nvram_read_swab() and document what the
code is really doing.
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>
diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index baa1f0e..9453918 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -2283,16 +2283,6 @@
return ret;
}
-static int tg3_nvram_read_swab(struct tg3 *tp, u32 offset, u32 *val)
-{
- int err;
- u32 tmp;
-
- err = tg3_nvram_read(tp, offset, &tmp);
- *val = swab32(tmp);
- return err;
-}
-
/* Ensures NVRAM data is in bytestream format. */
static int tg3_nvram_read_be32(struct tg3 *tp, u32 offset, __be32 *val)
{
@@ -10195,9 +10185,20 @@
return;
}
- if (tg3_nvram_read_swab(tp, 0xf0, &val) == 0) {
+ if (tg3_nvram_read(tp, 0xf0, &val) == 0) {
if (val != 0) {
- tp->nvram_size = (val >> 16) * 1024;
+ /* This is confusing. We want to operate on the
+ * 16-bit value at offset 0xf2. The tg3_nvram_read()
+ * call will read from NVRAM and byteswap the data
+ * according to the byteswapping settings for all
+ * other register accesses. This ensures the data we
+ * want will always reside in the lower 16-bits.
+ * However, the data in NVRAM is in LE format, which
+ * means the data from the NVRAM read will always be
+ * opposite the endianness of the CPU. The 16-bit
+ * byteswap then brings the data to CPU endianness.
+ */
+ tp->nvram_size = swab16((u16)(val & 0x0000ffff)) * 1024;
return;
}
}
@@ -11347,7 +11348,7 @@
static void __devinit tg3_read_partno(struct tg3 *tp)
{
- unsigned char vpd_data[256];
+ unsigned char vpd_data[256]; /* in little-endian format */
unsigned int i;
u32 magic;
@@ -11358,13 +11359,14 @@
for (i = 0; i < 256; i += 4) {
u32 tmp;
- if (tg3_nvram_read_swab(tp, 0x100 + i, &tmp))
+ /* The data is in little-endian format in NVRAM.
+ * Use the big-endian read routines to preserve
+ * the byte order as it exists in NVRAM.
+ */
+ if (tg3_nvram_read_be32(tp, 0x100 + i, &tmp))
goto out_not_found;
- vpd_data[i + 0] = ((tmp >> 0) & 0xff);
- vpd_data[i + 1] = ((tmp >> 8) & 0xff);
- vpd_data[i + 2] = ((tmp >> 16) & 0xff);
- vpd_data[i + 3] = ((tmp >> 24) & 0xff);
+ memcpy(&vpd_data[i], &tmp, sizeof(tmp));
}
} else {
int vpd_cap;
@@ -11390,7 +11392,7 @@
pci_read_config_dword(tp->pdev, vpd_cap + PCI_VPD_DATA,
&tmp);
v = cpu_to_le32(tmp);
- memcpy(&vpd_data[i], &v, 4);
+ memcpy(&vpd_data[i], &v, sizeof(v));
}
}
@@ -12358,14 +12360,10 @@
}
if (!addr_ok) {
/* Next, try NVRAM. */
- 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);
- dev->dev_addr[3] = ((lo >> 8) & 0xff);
- dev->dev_addr[4] = ((lo >> 16) & 0xff);
- dev->dev_addr[5] = ((lo >> 24) & 0xff);
+ if (!tg3_nvram_read_be32(tp, mac_offset + 0, &hi) &&
+ !tg3_nvram_read_be32(tp, mac_offset + 4, &lo)) {
+ memcpy(&dev->dev_addr[0], ((char *)&hi) + 2, 2);
+ memcpy(&dev->dev_addr[2], (char *)&lo, sizeof(lo));
}
/* Finally just fetch it out of the MAC control regs. */
else {