drm/amd/display: init dispclk from bootup clock for DCN315

[Why]
Driver does not pick up and save vbios's clocks during init clocks,
the dispclk in clk_mgr will keep 0.
OS might change the timing (lower the pixel clock) after boot.
Then driver will set the dispclk to lower when safe_to_lower is false,
for in clk_mgr dispclk is zero, it's illegal and causes garbage.

[How]
Dump and save the vbios's clocks, and init the dispclk in
dcn315_init_clocks.

Reviewed-by: Charlene Liu <charlene.liu@amd.com>
Signed-off-by: Zhongwei Zhang <Zhongwei.Zhang@amd.com>
Signed-off-by: Wayne Lin <wayne.lin@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

3 files changed, 87 insertions, 2 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn315/dcn315_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn315/dcn315_clk_mgr.c
index b315ed91e010..3a881451e9da 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn315/dcn315_clk_mgr.c
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn315/dcn315_clk_mgr.c
@@ -40,7 +40,7 @@
 #include "dm_helpers.h"
 
 #include "dc_dmub_srv.h"
-
+#include "reg_helper.h"
 #include "logger_types.h"
 #undef DC_LOGGER
 #define DC_LOGGER \
@@ -48,9 +48,43 @@
 
 #include "link_service.h"
 
+#define MAX_INSTANCE                                        7
+#define MAX_SEGMENT                                         8
+
+struct IP_BASE_INSTANCE {
+	unsigned int segment[MAX_SEGMENT];
+};
+
+struct IP_BASE {
+	struct IP_BASE_INSTANCE instance[MAX_INSTANCE];
+};
+
+static const struct IP_BASE CLK_BASE = { { { { 0x00016C00, 0x02401800, 0, 0, 0, 0, 0, 0 } },
+					{ { 0x00016E00, 0x02401C00, 0, 0, 0, 0, 0, 0 } },
+					{ { 0x00017000, 0x02402000, 0, 0, 0, 0, 0, 0 } },
+					{ { 0x00017200, 0x02402400, 0, 0, 0, 0, 0, 0 } },
+					{ { 0x0001B000, 0x0242D800, 0, 0, 0, 0, 0, 0 } },
+					{ { 0x0001B200, 0x0242DC00, 0, 0, 0, 0, 0, 0 } } } };
+
+#define regCLK1_CLK0_CURRENT_CNT			0x0314
+#define regCLK1_CLK0_CURRENT_CNT_BASE_IDX	0
+#define regCLK1_CLK1_CURRENT_CNT			0x0315
+#define regCLK1_CLK1_CURRENT_CNT_BASE_IDX	0
+#define regCLK1_CLK2_CURRENT_CNT			0x0316
+#define regCLK1_CLK2_CURRENT_CNT_BASE_IDX	0
+#define regCLK1_CLK3_CURRENT_CNT			0x0317
+#define regCLK1_CLK3_CURRENT_CNT_BASE_IDX	0
+#define regCLK1_CLK4_CURRENT_CNT			0x0318
+#define regCLK1_CLK4_CURRENT_CNT_BASE_IDX	0
+#define regCLK1_CLK5_CURRENT_CNT			0x0319
+#define regCLK1_CLK5_CURRENT_CNT_BASE_IDX	0
+
 #define TO_CLK_MGR_DCN315(clk_mgr)\
 	container_of(clk_mgr, struct clk_mgr_dcn315, base)
 
+#define REG(reg_name) \
+	(CLK_BASE.instance[0].segment[reg ## reg_name ## _BASE_IDX] + reg ## reg_name)
+
 #define UNSUPPORTED_DCFCLK 10000000
 #define MIN_DPP_DISP_CLK     100000
 
@@ -245,9 +279,38 @@ static void dcn315_update_clocks(struct clk_mgr *clk_mgr_base,
 	dc_wake_and_execute_dmub_cmd(dc->ctx, &cmd, DM_DMUB_WAIT_TYPE_WAIT);
 }
 
+static void dcn315_dump_clk_registers_internal(struct dcn35_clk_internal *internal, struct clk_mgr *clk_mgr_base)
+{
+	struct clk_mgr_internal *clk_mgr = TO_CLK_MGR_INTERNAL(clk_mgr_base);
+
+	// read dtbclk
+	internal->CLK1_CLK4_CURRENT_CNT = REG_READ(CLK1_CLK4_CURRENT_CNT);
+
+	// read dcfclk
+	internal->CLK1_CLK3_CURRENT_CNT = REG_READ(CLK1_CLK3_CURRENT_CNT);
+
+	// read dppclk
+	internal->CLK1_CLK1_CURRENT_CNT = REG_READ(CLK1_CLK1_CURRENT_CNT);
+
+	// read dprefclk
+	internal->CLK1_CLK2_CURRENT_CNT = REG_READ(CLK1_CLK2_CURRENT_CNT);
+
+	// read dispclk
+	internal->CLK1_CLK0_CURRENT_CNT = REG_READ(CLK1_CLK0_CURRENT_CNT);
+}
+
 static void dcn315_dump_clk_registers(struct clk_state_registers_and_bypass *regs_and_bypass,
 		struct clk_mgr *clk_mgr_base, struct clk_log_info *log_info)
 {
+	struct dcn35_clk_internal internal = {0};
+
+	dcn315_dump_clk_registers_internal(&internal, clk_mgr_base);
+
+	regs_and_bypass->dcfclk = internal.CLK1_CLK3_CURRENT_CNT / 10;
+	regs_and_bypass->dprefclk = internal.CLK1_CLK2_CURRENT_CNT / 10;
+	regs_and_bypass->dispclk = internal.CLK1_CLK0_CURRENT_CNT / 10;
+	regs_and_bypass->dppclk = internal.CLK1_CLK1_CURRENT_CNT / 10;
+	regs_and_bypass->dtbclk = internal.CLK1_CLK4_CURRENT_CNT / 10;
 	return;
 }
 
@@ -594,13 +657,32 @@ static struct clk_mgr_funcs dcn315_funcs = {
 	.get_dp_ref_clk_frequency = dce12_get_dp_ref_freq_khz,
 	.get_dtb_ref_clk_frequency = dcn31_get_dtb_ref_freq_khz,
 	.update_clocks = dcn315_update_clocks,
-	.init_clocks = dcn31_init_clocks,
+	.init_clocks = dcn315_init_clocks,
 	.enable_pme_wa = dcn315_enable_pme_wa,
 	.are_clock_states_equal = dcn31_are_clock_states_equal,
 	.notify_wm_ranges = dcn315_notify_wm_ranges
 };
 extern struct clk_mgr_funcs dcn3_fpga_funcs;
 
+void dcn315_init_clocks(struct clk_mgr *clk_mgr)
+{
+	struct clk_mgr_internal *clk_mgr_int = TO_CLK_MGR_INTERNAL(clk_mgr);
+	uint32_t ref_dtbclk = clk_mgr->clks.ref_dtbclk_khz;
+	struct clk_mgr_dcn315 *clk_mgr_dcn315 = TO_CLK_MGR_DCN315(clk_mgr_int);
+	struct clk_log_info log_info = {0};
+
+	memset(&(clk_mgr->clks), 0, sizeof(struct dc_clocks));
+	// Assumption is that boot state always supports pstate
+	clk_mgr->clks.ref_dtbclk_khz = ref_dtbclk;	// restore ref_dtbclk
+	clk_mgr->clks.p_state_change_support = true;
+	clk_mgr->clks.prev_p_state_change_support = true;
+	clk_mgr->clks.pwr_state = DCN_PWR_STATE_UNKNOWN;
+	clk_mgr->clks.zstate_support = DCN_ZSTATE_SUPPORT_UNKNOWN;
+
+	dcn315_dump_clk_registers(&clk_mgr->boot_snapshot, &clk_mgr_dcn315->base.base, &log_info);
+	clk_mgr->clks.dispclk_khz =  clk_mgr->boot_snapshot.dispclk * 1000;
+}
+
 void dcn315_clk_mgr_construct(
 		struct dc_context *ctx,
 		struct clk_mgr_dcn315 *clk_mgr,
@@ -661,6 +743,7 @@ void dcn315_clk_mgr_construct(
 	/* Saved clocks configured at boot for debug purposes */
 	dcn315_dump_clk_registers(&clk_mgr->base.base.boot_snapshot,
 				  &clk_mgr->base.base, &log_info);
+	clk_mgr->base.base.clks.dispclk_khz =  clk_mgr->base.base.boot_snapshot.dispclk * 1000;
 
 	clk_mgr->base.base.dprefclk_khz = 600000;
 	clk_mgr->base.base.dprefclk_khz = dcn315_smu_get_dpref_clk(&clk_mgr->base);
diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn315/dcn315_clk_mgr.h b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn315/dcn315_clk_mgr.h
index ac36ddf5dd1a..642ae3d4a790 100644
--- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn315/dcn315_clk_mgr.h
+++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn315/dcn315_clk_mgr.h
@@ -44,6 +44,7 @@ void dcn315_clk_mgr_construct(struct dc_context *ctx,
 		struct pp_smu_funcs *pp_smu,
 		struct dccg *dccg);
 
+void dcn315_init_clocks(struct clk_mgr *clk_mgr);
 void dcn315_clk_mgr_destroy(struct clk_mgr_internal *clk_mgr_int);
 
 #endif //__DCN315_CLK_MGR_H__
diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn315/dcn315_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn315/dcn315_resource.c
index 38f6328cda92..4e962f522f1b 100644
--- a/drivers/gpu/drm/amd/display/dc/resource/dcn315/dcn315_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/resource/dcn315/dcn315_resource.c
@@ -889,6 +889,7 @@ static const struct dc_debug_options debug_defaults_drv = {
 	},
 	.psr_power_use_phy_fsm = 0,
 	.using_dml2 = false,
+	.min_disp_clk_khz = 100000,
 };
 
 static const struct dc_check_config config_defaults = {