drm/amdgpu/smu_v11: Unify and fix power limits

[Why]
On Navi10, and presumably arcterus, updating pp_table via sysfs would
not re-scale the maximum possible power limit one can set. On navi10,
the SMU code ignored the power percentage overdrive setting entirely,
and would not allow you to exceed the default power limit at all.

[How]
Adding a function to the SMU interface to get the pptable version of the
default power limit allows ASIC-specific code to provide the correct
maximum-settable power limit for the current pptable.

v3: fix spelling (Alex)

Reviewed-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Matt Coffin <mcoffin13@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 37 insertions, 3 deletions

diff --git a/drivers/gpu/drm/amd/powerplay/smu_v11_0.c b/drivers/gpu/drm/amd/powerplay/smu_v11_0.c
index c4f67ee8840e..fc9679ea2368 100644
--- a/drivers/gpu/drm/amd/powerplay/smu_v11_0.c
+++ b/drivers/gpu/drm/amd/powerplay/smu_v11_0.c
@@ -24,6 +24,8 @@
 #include <linux/module.h>
 #include <linux/pci.h>
 
+#define SMU_11_0_PARTIAL_PPTABLE
+
 #include "pp_debug.h"
 #include "amdgpu.h"
 #include "amdgpu_smu.h"
@@ -31,6 +33,7 @@
 #include "atomfirmware.h"
 #include "amdgpu_atomfirmware.h"
 #include "smu_v11_0.h"
+#include "smu_v11_0_pptable.h"
 #include "soc15_common.h"
 #include "atom.h"
 #include "amd_pcie.h"
@@ -1045,13 +1048,44 @@ int smu_v11_0_init_max_sustainable_clocks(struct smu_context *smu)
 	return 0;
 }
 
+uint32_t smu_v11_0_get_max_power_limit(struct smu_context *smu) {
+	uint32_t od_limit, max_power_limit;
+	struct smu_11_0_powerplay_table *powerplay_table = NULL;
+	struct smu_table_context *table_context = &smu->smu_table;
+	powerplay_table = table_context->power_play_table;
+
+	max_power_limit = smu_get_pptable_power_limit(smu);
+
+	if (!max_power_limit) {
+		// If we couldn't get the table limit, fall back on first-read value
+		if (!smu->default_power_limit)
+			smu->default_power_limit = smu->power_limit;
+		max_power_limit = smu->default_power_limit;
+	}
+
+	if (smu->od_enabled) {
+		od_limit = le32_to_cpu(powerplay_table->overdrive_table.max[SMU_11_0_ODSETTING_POWERPERCENTAGE]);
+
+		pr_debug("ODSETTING_POWERPERCENTAGE: %d (default: %d)\n", od_limit, smu->default_power_limit);
+
+		max_power_limit *= (100 + od_limit);
+		max_power_limit /= 100;
+	}
+
+	return max_power_limit;
+}
+
 int smu_v11_0_set_power_limit(struct smu_context *smu, uint32_t n)
 {
 	int ret = 0;
+	uint32_t max_power_limit;
+
+	max_power_limit = smu_v11_0_get_max_power_limit(smu);
 
-	if (n > smu->default_power_limit) {
-		pr_err("New power limit is over the max allowed %d\n",
-				smu->default_power_limit);
+	if (n > max_power_limit) {
+		pr_err("New power limit (%d) is over the max allowed %d\n",
+				n,
+				max_power_limit);
 		return -EINVAL;
 	}