drm/amd/display: set per pipe dppclk to 0 when dpp is off

The 'commit 52e4fdf ("drm/amd/display: use low clocks for no plane
configs")' introduced a change that set low clock values for DCN31 and
DCN32. As a result of these changes, DC started to spam the log with the
following warning:

------------[ cut here ]------------
WARNING: CPU: 8 PID: 1486 at
drivers/gpu/drm/amd/amdgpu/../display/dc/dcn20/dcn20_dccg.c:58
dccg2_update_dpp_dto+0x3f/0xf0 [amdgpu]
[..]
CPU: 8 PID: 1486 Comm: kms_atomic Tainted: G W 5.18.0+ #1
RIP: 0010:dccg2_update_dpp_dto+0x3f/0xf0 [amdgpu]
RSP: 0018:ffffbbd8025334d0 EFLAGS: 00010206
RAX: 00000000000001ee RBX: ffffa02c87dd3de0 RCX: 00000000000a7f80
RDX: 000000000007dec3 RSI: 0000000000000000 RDI: ffffa02c87dd3de0
RBP: ffffbbd8025334e8 R08: 0000000000000001 R09: 0000000000000005
R10: 00000000000331a0 R11: ffffffffc0b03d80 R12: ffffa02ca576d000
R13: ffffa02cd02c0000 R14: 00000000001453bc R15: ffffa02cdc280000
[..]
dcn20_update_clocks_update_dpp_dto+0x4e/0xa0 [amdgpu]
dcn32_update_clocks+0x5d9/0x650 [amdgpu]
dcn20_prepare_bandwidth+0x49/0x100 [amdgpu]
dcn30_prepare_bandwidth+0x63/0x80 [amdgpu]
dc_commit_state_no_check+0x39d/0x13e0 [amdgpu]
dc_commit_streams+0x1f9/0x3b0 [amdgpu]
dc_commit_state+0x37/0x120 [amdgpu]
amdgpu_dm_atomic_commit_tail+0x5e5/0x2520 [amdgpu]
? _raw_spin_unlock_irqrestore+0x1f/0x40
? down_trylock+0x2c/0x40
? vprintk_emit+0x186/0x2c0
? vprintk_default+0x1d/0x20
? vprintk+0x4e/0x60

We can easily trigger this issue by using a 4k@120 or a 2k@165 and
running some of the kms_atomic tests. This warning is triggered because
the per-pipe clock update is not happening; this commit fixes this issue
by ensuring that DPPCLK is updated when calculating the watermark and
dlg is invoked.

Fixes: 2641c7b ("drm/amd/display: use low clocks for no plane configs")
Reported-by: Mark Broadworth <[email protected]>
Reviewed-by: Rodrigo Siqueira <[email protected]>
Signed-off-by: Dmytro Laktyushkin <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>

Author: Dmytro Laktyushkin

drivers/gpu/drm/amd/display/dc/dml/dcn31/dcn31_fpu.c

@@ -559,6 +559,9 @@ void dcn31_calculate_wm_and_dlg_fp(
 		context->bw_ctx.bw.dcn.clk.dramclk_khz = 0;
 		context->bw_ctx.bw.dcn.clk.fclk_khz = 0;
 		context->bw_ctx.bw.dcn.clk.p_state_change_support = true;
+		for (i = 0; i < dc->res_pool->pipe_count; i++)
+			if (context->res_ctx.pipe_ctx[i].stream)
+				context->res_ctx.pipe_ctx[i].plane_res.bw.dppclk_khz = 0;
 	}
 }
 

drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.c

@@ -1320,7 +1320,10 @@ static void dcn32_calculate_dlg_params(struct dc *dc, struct dc_state *context,
 
 		if (context->bw_ctx.bw.dcn.clk.dppclk_khz < pipes[pipe_idx].clks_cfg.dppclk_mhz * 1000)
 			context->bw_ctx.bw.dcn.clk.dppclk_khz = pipes[pipe_idx].clks_cfg.dppclk_mhz * 1000;
-		context->res_ctx.pipe_ctx[i].plane_res.bw.dppclk_khz = pipes[pipe_idx].clks_cfg.dppclk_mhz * 1000;
+		if (context->res_ctx.pipe_ctx[i].plane_state)
+			context->res_ctx.pipe_ctx[i].plane_res.bw.dppclk_khz = pipes[pipe_idx].clks_cfg.dppclk_mhz * 1000;
+		else
+			context->res_ctx.pipe_ctx[i].plane_res.bw.dppclk_khz = 0;
 		context->res_ctx.pipe_ctx[i].pipe_dlg_param = pipes[pipe_idx].pipe.dest;
 		pipe_idx++;
 	}