From: Samson Tam Samson.Tam@amd.com
commit 682439fffad9fa9a38d37dd1b1318e9374232213 upstream.
[Why] Reading pipe_fuses from register may have invalid bits set, which may affect the num_pipes erroneously.
[How] Add read_pipes_fuses() call and filter bits based on expected number of pipes.
Reviewed-by: Alvin Lee Alvin.Lee2@amd.com Acked-by: Alan Liu HaoPing.Liu@amd.com Signed-off-by: Samson Tam Samson.Tam@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org # 6.1.x Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c | 10 +++++++++- drivers/gpu/drm/amd/display/dc/dcn321/dcn321_resource.c | 10 +++++++++- 2 files changed, 18 insertions(+), 2 deletions(-)
--- a/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c +++ b/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_resource.c @@ -2037,6 +2037,14 @@ static struct resource_funcs dcn32_res_p .remove_phantom_pipes = dcn32_remove_phantom_pipes, };
+static uint32_t read_pipe_fuses(struct dc_context *ctx) +{ + uint32_t value = REG_READ(CC_DC_PIPE_DIS); + /* DCN32 support max 4 pipes */ + value = value & 0xf; + return value; +} +
static bool dcn32_resource_construct( uint8_t num_virtual_links, @@ -2079,7 +2087,7 @@ static bool dcn32_resource_construct( pool->base.res_cap = &res_cap_dcn32; /* max number of pipes for ASIC before checking for pipe fuses */ num_pipes = pool->base.res_cap->num_timing_generator; - pipe_fuses = REG_READ(CC_DC_PIPE_DIS); + pipe_fuses = read_pipe_fuses(ctx);
for (i = 0; i < pool->base.res_cap->num_timing_generator; i++) if (pipe_fuses & 1 << i) --- a/drivers/gpu/drm/amd/display/dc/dcn321/dcn321_resource.c +++ b/drivers/gpu/drm/amd/display/dc/dcn321/dcn321_resource.c @@ -1621,6 +1621,14 @@ static struct resource_funcs dcn321_res_ .remove_phantom_pipes = dcn32_remove_phantom_pipes, };
+static uint32_t read_pipe_fuses(struct dc_context *ctx) +{ + uint32_t value = REG_READ(CC_DC_PIPE_DIS); + /* DCN321 support max 4 pipes */ + value = value & 0xf; + return value; +} +
static bool dcn321_resource_construct( uint8_t num_virtual_links, @@ -1663,7 +1671,7 @@ static bool dcn321_resource_construct( pool->base.res_cap = &res_cap_dcn321; /* max number of pipes for ASIC before checking for pipe fuses */ num_pipes = pool->base.res_cap->num_timing_generator; - pipe_fuses = REG_READ(CC_DC_PIPE_DIS); + pipe_fuses = read_pipe_fuses(ctx);
for (i = 0; i < pool->base.res_cap->num_timing_generator; i++) if (pipe_fuses & 1 << i)