@@ -44,6 +44,41 @@ static char *pre_emph_names[] = {
};
/***** radeon AUX functions *****/
+
+/* Atom needs data in little endian format
+ * so swap as appropriate when copying data to
+ * or from atom. Note that atom operates on
+ * dw units.
+ */
+static void radeon_copy_swap(u8 *dst, u8 *src, u8 num_bytes, bool to_le)
+{
+#ifdef __BIG_ENDIAN
+ u8 src_tmp[20], dst_tmp[20]; /* used for byteswapping */
+ u32 *dst32, *src32;
+ int i;
+
+ memcpy(src_tmp, src, num_bytes);
+ src32 = (u32 *)src_tmp;
+ dst32 = (u32 *)dst_tmp;
+ if (to_le) {
+ for (i = 0; i < ((num_bytes + 3) / 4); i++)
+ dst32[i] = cpu_to_le32(src32[i]);
+ memcpy(dst, dst_tmp, num_bytes);
+ } else {
+ u8 dws = num_bytes & ~3;
+ for (i = 0; i < ((num_bytes + 3) / 4); i++)
+ dst32[i] = le32_to_cpu(src32[i]);
+ memcpy(dst, dst_tmp, dws);
+ if (num_bytes % 4) {
+ for (i = 0; i < (num_bytes % 4); i++)
+ dst[dws+i] = dst_tmp[dws+i];
+ }
+ }
+#else
+ memcpy(dst, src, num_bytes);
+#endif
+}
+
union aux_channel_transaction {
PROCESS_AUX_CHANNEL_TRANSACTION_PS_ALLOCATION v1;
PROCESS_AUX_CHANNEL_TRANSACTION_PARAMETERS_V2 v2;
@@ -65,10 +100,10 @@ static int radeon_process_aux_ch(struct radeon_i2c_chan *chan,
base = (unsigned char *)(rdev->mode_info.atom_context->scratch + 1);
- memcpy(base, send, send_bytes);
+ radeon_copy_swap(base, send, send_bytes, true);
- args.v1.lpAuxRequest = 0 + 4;
- args.v1.lpDataOut = 16 + 4;
+ args.v1.lpAuxRequest = cpu_to_le16((u16)(0 + 4));
+ args.v1.lpDataOut = cpu_to_le16((u16)(16 + 4));
args.v1.ucDataOutLen = 0;
args.v1.ucChannelID = chan->rec.i2c_id;
args.v1.ucDelay = delay / 10;
@@ -102,7 +137,7 @@ static int radeon_process_aux_ch(struct radeon_i2c_chan *chan,
recv_bytes = recv_size;
if (recv && recv_size)
- memcpy(recv, base + 16, recv_bytes);
+ radeon_copy_swap(recv, base + 16, recv_bytes, false);
return recv_bytes;
}
This is a note to let you know that I have just added a patch titled drm/radeon: fix endian issues with DP handling (v3) to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue This patch is scheduled to be released in version 3.8.13.7. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.8.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 65a57d9cbf80a90856ba53e6cee8bfd69f0fc90a Mon Sep 17 00:00:00 2001 From: Alex Deucher <alexander.deucher@amd.com> Date: Thu, 18 Jul 2013 11:13:53 -0400 Subject: drm/radeon: fix endian issues with DP handling (v3) commit 34be8c9af7b8728465963740fc11136ae90dfc36 upstream. The atom interpreter expects data in LE format, so swap the message buffer as apprioriate. v2: properly handle non-dw aligned byte counts. v3: properly handle remainder Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: Dong He <hedonghust@gmail.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/gpu/drm/radeon/atombios_dp.c | 43 ++++++++++++++++++++++++++++++++---- 1 file changed, 39 insertions(+), 4 deletions(-) -- 1.8.1.2