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path: root/drivers/gpu/drm/radeon/atombios_dp.c
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Diffstat (limited to 'drivers/gpu/drm/radeon/atombios_dp.c')
-rw-r--r--drivers/gpu/drm/radeon/atombios_dp.c46
1 files changed, 22 insertions, 24 deletions
diff --git a/drivers/gpu/drm/radeon/atombios_dp.c b/drivers/gpu/drm/radeon/atombios_dp.c
index 432cb46f6a34..3e798593e042 100644
--- a/drivers/gpu/drm/radeon/atombios_dp.c
+++ b/drivers/gpu/drm/radeon/atombios_dp.c
@@ -45,34 +45,32 @@ 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.
+/* 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.
+ *
+ * Use to_le=true when sending data to atom and provide at least
+ * ALIGN(num_bytes,4) bytes in the dst buffer.
+ *
+ * Use to_le=false when receiving data from atom and provide ALIGN(num_bytes,4)
+ * byes in the src buffer.
*/
void radeon_atom_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;
+ u32 src_tmp[5], dst_tmp[5];
int i;
+ u8 align_num_bytes = ALIGN(num_bytes, 4);
- 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);
+ memcpy(src_tmp, src, num_bytes);
+ for (i = 0; i < align_num_bytes / 4; i++)
+ dst_tmp[i] = cpu_to_le32(src_tmp[i]);
+ memcpy(dst, dst_tmp, align_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];
- }
+ memcpy(src_tmp, src, align_num_bytes);
+ for (i = 0; i < align_num_bytes / 4; i++)
+ dst_tmp[i] = le32_to_cpu(src_tmp[i]);
+ memcpy(dst, dst_tmp, num_bytes);
}
#else
memcpy(dst, src, num_bytes);
@@ -304,10 +302,10 @@ static int convert_bpc_to_bpp(int bpc)
/***** radeon specific DP functions *****/
-int radeon_dp_get_dp_link_config(struct drm_connector *connector,
- const u8 dpcd[DP_DPCD_SIZE],
- unsigned pix_clock,
- unsigned *dp_lanes, unsigned *dp_rate)
+static int radeon_dp_get_dp_link_config(struct drm_connector *connector,
+ const u8 dpcd[DP_DPCD_SIZE],
+ unsigned pix_clock,
+ unsigned *dp_lanes, unsigned *dp_rate)
{
int bpp = convert_bpc_to_bpp(radeon_get_monitor_bpc(connector));
static const unsigned link_rates[3] = { 162000, 270000, 540000 };