From: Meenakshikumar Somasundaram Date: Wed, 10 Apr 2024 14:46:35 +0000 (-0400) Subject: drm/amd/display: Allocate zero bw after bw alloc enable X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=46fe9cb1a9e62f4e6229f48ae303ef8e6c1fdc64;p=linux.git drm/amd/display: Allocate zero bw after bw alloc enable [Why] During DP tunnel creation, CM preallocates BW and reduces estimated BW of other DPIA. CM release preallocation only when allocation is complete. Display mode validation logic validates timings based on bw available per host router. In multi display setup, this causes bw allocation failure when allocation greater than estimated bw. [How] Do zero alloc to make the CM to release preallocation and update estimated BW correctly for all DPIAs per host router. Reviewed-by: PeiChen Huang Acked-by: Aurabindo Pillai Signed-off-by: Meenakshikumar Somasundaram Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia_bw.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia_bw.c index 5491b707cec88..5a965c26bf209 100644 --- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia_bw.c +++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia_bw.c @@ -270,7 +270,7 @@ static void set_usb4_req_bw_req(struct dc_link *link, int req_bw) /* Error check whether requested and allocated are equal */ req_bw = requested_bw * (Kbps_TO_Gbps / link->dpia_bw_alloc_config.bw_granularity); - if (req_bw == link->dpia_bw_alloc_config.allocated_bw) { + if (req_bw && (req_bw == link->dpia_bw_alloc_config.allocated_bw)) { DC_LOG_ERROR("%s: Request bw equals to allocated bw for link(%d)\n", __func__, link->link_index); } @@ -341,6 +341,14 @@ bool link_dp_dpia_set_dptx_usb4_bw_alloc_support(struct dc_link *link) ret = true; init_usb4_bw_struct(link); link->dpia_bw_alloc_config.bw_alloc_enabled = true; + + /* + * During DP tunnel creation, CM preallocates BW and reduces estimated BW of other + * DPIA. CM release preallocation only when allocation is complete. Do zero alloc + * to make the CM to release preallocation and update estimated BW correctly for + * all DPIAs per host router + */ + link_dp_dpia_allocate_usb4_bandwidth_for_stream(link, 0); } }