dcn32_init_hw() checks dc->clk_mgr before calling init_clocks(), so the clock manager is not treated as unconditionally present on this path. However, dcn32_initialize_min_clocks() later dereferences dc->clk_mgr, bw_params, and clk_mgr callbacks without validating them.
Add the required guards in dcn32_initialize_min_clocks() before accessing clk_mgr-dependent state, and check callback presence before calling get_dispclk_from_dentist() and update_clocks(). Also guard the later update_bw_bounding_box() call in the FAMS2-disabled path since it also dereferences dc->clk_mgr->bw_params. This keeps clk_mgr handling consistent in the DCN32 HW init flow and avoids possible NULL pointer dereferences reported by Smatch. Fixes the below: drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn32/dcn32_hwseq.c:1012 dcn32_init_hw() error: we previously assumed 'dc->clk_mgr' could be null (see line 978) Cc: Roman Li <[email protected]> Cc: Alex Hung <[email protected]> Cc: Jerry Zuo <[email protected]> Cc: Sun peng Li <[email protected]> Cc: Tom Chung <[email protected]> Cc: Dan Carpenter <[email protected]> Cc: Aurabindo Pillai <[email protected]> Signed-off-by: Srinivasan Shanmugam <[email protected]> --- .../drm/amd/display/dc/hwss/dcn32/dcn32_hwseq.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn32/dcn32_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn32/dcn32_hwseq.c index a0aaa727e9fa..e5d93dd348dd 100644 --- a/drivers/gpu/drm/amd/display/dc/hwss/dcn32/dcn32_hwseq.c +++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn32/dcn32_hwseq.c @@ -757,6 +757,9 @@ static void dcn32_initialize_min_clocks(struct dc *dc) { struct dc_clocks *clocks = &dc->current_state->bw_ctx.bw.dcn.clk; + if (!dc->clk_mgr || !dc->clk_mgr->bw_params || !dc->clk_mgr->funcs) + return; + clocks->dcfclk_deep_sleep_khz = DCN3_2_DCFCLK_DS_INIT_KHZ; clocks->dcfclk_khz = dc->clk_mgr->bw_params->clk_table.entries[0].dcfclk_mhz * 1000; clocks->socclk_khz = dc->clk_mgr->bw_params->clk_table.entries[0].socclk_mhz * 1000; @@ -765,9 +768,10 @@ static void dcn32_initialize_min_clocks(struct dc *dc) clocks->ref_dtbclk_khz = dc->clk_mgr->bw_params->clk_table.entries[0].dtbclk_mhz * 1000; clocks->fclk_p_state_change_support = true; clocks->p_state_change_support = true; + if (dc->debug.disable_boot_optimizations) { clocks->dispclk_khz = dc->clk_mgr->bw_params->clk_table.entries[0].dispclk_mhz * 1000; - } else { + } else if (dc->clk_mgr->funcs->get_dispclk_from_dentist) { /* Even though DPG_EN = 1 for the connected display, it still requires the * correct timing so we cannot set DISPCLK to min freq or it could cause * audio corruption. Read current DISPCLK from DENTIST and request the same @@ -776,10 +780,10 @@ static void dcn32_initialize_min_clocks(struct dc *dc) clocks->dispclk_khz = dc->clk_mgr->funcs->get_dispclk_from_dentist(dc->clk_mgr); } - dc->clk_mgr->funcs->update_clocks( - dc->clk_mgr, - dc->current_state, - true); + if (dc->clk_mgr->funcs->update_clocks) + dc->clk_mgr->funcs->update_clocks(dc->clk_mgr, + dc->current_state, + true); } void dcn32_init_hw(struct dc *dc) @@ -1007,7 +1011,8 @@ void dcn32_init_hw(struct dc *dc) DMUB_FW_VERSION(7, 0, 35)) { /* FAMS2 is disabled */ dc->debug.fams2_config.bits.enable = false; - if (dc->debug.using_dml2 && dc->res_pool->funcs->update_bw_bounding_box) { + if (dc->debug.using_dml2 && dc->res_pool->funcs->update_bw_bounding_box && + dc->clk_mgr && dc->clk_mgr->bw_params) { /* update bounding box if FAMS2 disabled */ dc->res_pool->funcs->update_bw_bounding_box(dc, dc->clk_mgr->bw_params); } -- 2.34.1
