[PATCH] drm/amd: Fix logic error in sienna_cichlid_update_pcie_parameters()

[Mario Limonciello]

While aligning SMU11 with SMU13 implementation an assumption was made that
`dpm_context->dpm_tables.pcie_table` was populated in dpm table initialization
like in SMU13 but it isn't.

So restore some of the original logic and instead just check for
amdgpu_device_pcie_dynamic_switching_supported() to decide whether to hardcode
values; erring on the side of performance.

Cc: stable at vger.kernel.org # 6.1+
Reported-and-tested-by: Umio Yasuno <coelacanth_dream at protonmail.com>
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/1447#note_2101382
Fixes: e701156ccc6c ("drm/amd: Align SMU11 SMU_MSG_OverridePcieParameters implementation with SMU13")
Signed-off-by: Mario Limonciello <mario.limonciello at amd.com>
---
 .../amd/pm/swsmu/smu11/sienna_cichlid_ppt.c   | 41 +++++++++++--------
 1 file changed, 23 insertions(+), 18 deletions(-)

diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c b/drivers/gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c
index f0800c0c5168..9119b0df2419 100644
--- a/drivers/gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c
+++ b/drivers/gpu/drm/amd/pm/swsmu/smu11/sienna_cichlid_ppt.c
@@ -2081,36 +2081,41 @@ static int sienna_cichlid_display_disable_memory_clock_switch(struct smu_context
 	return ret;
 }
 
+#define MAX(a, b)	((a) > (b) ? (a) : (b))
+
 static int sienna_cichlid_update_pcie_parameters(struct smu_context *smu,
 					 uint32_t pcie_gen_cap,
 					 uint32_t pcie_width_cap)
 {
 	struct smu_11_0_dpm_context *dpm_context = smu->smu_dpm.dpm_context;
 	struct smu_11_0_pcie_table *pcie_table = &dpm_context->dpm_tables.pcie_table;
-	u32 smu_pcie_arg;
+	uint8_t *table_member1, *table_member2;
+	uint32_t min_gen_speed, max_gen_speed;
+	uint32_t min_lane_width, max_lane_width;
+	uint32_t smu_pcie_arg;
 	int ret, i;
 
-	/* PCIE gen speed and lane width override */
-	if (!amdgpu_device_pcie_dynamic_switching_supported()) {
-		if (pcie_table->pcie_gen[NUM_LINK_LEVELS - 1] < pcie_gen_cap)
-			pcie_gen_cap = pcie_table->pcie_gen[NUM_LINK_LEVELS - 1];
+	GET_PPTABLE_MEMBER(PcieGenSpeed, &table_member1);
+	GET_PPTABLE_MEMBER(PcieLaneCount, &table_member2);
 
-		if (pcie_table->pcie_lane[NUM_LINK_LEVELS - 1] < pcie_width_cap)
-			pcie_width_cap = pcie_table->pcie_lane[NUM_LINK_LEVELS - 1];
+	min_gen_speed = MAX(0, table_member1[0]);
+	max_gen_speed = MIN(pcie_gen_cap, table_member1[1]);
+	min_gen_speed = min_gen_speed > max_gen_speed ?
+			max_gen_speed : min_gen_speed;
+	min_lane_width = MAX(1, table_member2[0]);
+	max_lane_width = MIN(pcie_width_cap, table_member2[1]);
+	min_lane_width = min_lane_width > max_lane_width ?
+			 max_lane_width : min_lane_width;
 
-		/* Force all levels to use the same settings */
-		for (i = 0; i < NUM_LINK_LEVELS; i++) {
-			pcie_table->pcie_gen[i] = pcie_gen_cap;
-			pcie_table->pcie_lane[i] = pcie_width_cap;
-		}
+	if (!amdgpu_device_pcie_dynamic_switching_supported()) {
+		pcie_table->pcie_gen[0] = max_gen_speed;
+		pcie_table->pcie_lane[0] = max_lane_width;
 	} else {
-		for (i = 0; i < NUM_LINK_LEVELS; i++) {
-			if (pcie_table->pcie_gen[i] > pcie_gen_cap)
-				pcie_table->pcie_gen[i] = pcie_gen_cap;
-			if (pcie_table->pcie_lane[i] > pcie_width_cap)
-				pcie_table->pcie_lane[i] = pcie_width_cap;
-		}
+		pcie_table->pcie_gen[0] = min_gen_speed;
+		pcie_table->pcie_lane[0] = min_lane_width;
 	}
+	pcie_table->pcie_gen[1] = max_gen_speed;
+	pcie_table->pcie_lane[1] = max_lane_width;
 
 	for (i = 0; i < NUM_LINK_LEVELS; i++) {
 		smu_pcie_arg = (i << 16 |
-- 
2.34.1