diff options
Diffstat (limited to 'drivers/net/ethernet/chelsio/cxgb4/t4_hw.c')
| -rw-r--r-- | drivers/net/ethernet/chelsio/cxgb4/t4_hw.c | 54 |
1 files changed, 44 insertions, 10 deletions
diff --git a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c index 4d643b65265e..853c38997c82 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c +++ b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c @@ -449,7 +449,7 @@ int t4_edc_read(struct adapter *adap, int idx, u32 addr, __be32 *data, u64 *ecc) * @mtype: memory type: MEM_EDC0, MEM_EDC1 or MEM_MC * @addr: address within indicated memory type * @len: amount of memory to transfer - * @buf: host memory buffer + * @hbuf: host memory buffer * @dir: direction of transfer T4_MEMORY_READ (1) or T4_MEMORY_WRITE (0) * * Reads/writes an [almost] arbitrary memory region in the firmware: the @@ -460,15 +460,17 @@ int t4_edc_read(struct adapter *adap, int idx, u32 addr, __be32 *data, u64 *ecc) * caller's responsibility to perform appropriate byte order conversions. */ int t4_memory_rw(struct adapter *adap, int win, int mtype, u32 addr, - u32 len, __be32 *buf, int dir) + u32 len, void *hbuf, int dir) { u32 pos, offset, resid, memoffset; u32 edc_size, mc_size, win_pf, mem_reg, mem_aperture, mem_base; + u32 *buf; /* Argument sanity checks ... */ - if (addr & 0x3) + if (addr & 0x3 || (uintptr_t)hbuf & 0x3) return -EINVAL; + buf = (u32 *)hbuf; /* It's convenient to be able to handle lengths which aren't a * multiple of 32-bits because we often end up transferring files to @@ -532,14 +534,45 @@ int t4_memory_rw(struct adapter *adap, int win, int mtype, u32 addr, /* Transfer data to/from the adapter as long as there's an integral * number of 32-bit transfers to complete. + * + * A note on Endianness issues: + * + * The "register" reads and writes below from/to the PCI-E Memory + * Window invoke the standard adapter Big-Endian to PCI-E Link + * Little-Endian "swizzel." As a result, if we have the following + * data in adapter memory: + * + * Memory: ... | b0 | b1 | b2 | b3 | ... + * Address: i+0 i+1 i+2 i+3 + * + * Then a read of the adapter memory via the PCI-E Memory Window + * will yield: + * + * x = readl(i) + * 31 0 + * [ b3 | b2 | b1 | b0 ] + * + * If this value is stored into local memory on a Little-Endian system + * it will show up correctly in local memory as: + * + * ( ..., b0, b1, b2, b3, ... ) + * + * But on a Big-Endian system, the store will show up in memory + * incorrectly swizzled as: + * + * ( ..., b3, b2, b1, b0, ... ) + * + * So we need to account for this in the reads and writes to the + * PCI-E Memory Window below by undoing the register read/write + * swizzels. */ while (len > 0) { if (dir == T4_MEMORY_READ) - *buf++ = (__force __be32) t4_read_reg(adap, - mem_base + offset); + *buf++ = le32_to_cpu((__force __le32)t4_read_reg(adap, + mem_base + offset)); else t4_write_reg(adap, mem_base + offset, - (__force u32) *buf++); + (__force u32)cpu_to_le32(*buf++)); offset += sizeof(__be32); len -= sizeof(__be32); @@ -568,15 +601,16 @@ int t4_memory_rw(struct adapter *adap, int win, int mtype, u32 addr, */ if (resid) { union { - __be32 word; + u32 word; char byte[4]; } last; unsigned char *bp; int i; if (dir == T4_MEMORY_READ) { - last.word = (__force __be32) t4_read_reg(adap, - mem_base + offset); + last.word = le32_to_cpu( + (__force __le32)t4_read_reg(adap, + mem_base + offset)); for (bp = (unsigned char *)buf, i = resid; i < 4; i++) bp[i] = last.byte[i]; } else { @@ -584,7 +618,7 @@ int t4_memory_rw(struct adapter *adap, int win, int mtype, u32 addr, for (i = resid; i < 4; i++) last.byte[i] = 0; t4_write_reg(adap, mem_base + offset, - (__force u32) last.word); + (__force u32)cpu_to_le32(last.word)); } } |