Re: [PATCH 20/25] drm/i915/ltphy: Define the LT Phy state compare function

["Murthy, Arun R" <arun.r.murthy@intel.com>]

On 15-10-2025 09:38, Suraj Kandpal wrote:
> Define function to compare the state and if mismatch is detected
> dump both the states.
>
> Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
> ---

Reviewed-by: Arun R Murthy <arun.r.murthy@intel.com>

Thanks and Regards,
Arun R Murthy
--------------------

>   drivers/gpu/drm/i915/display/intel_display.c | 33 +++++++++++++++++++-
>   drivers/gpu/drm/i915/display/intel_lt_phy.c  | 30 ++++++++++++++++++
>   drivers/gpu/drm/i915/display/intel_lt_phy.h  |  6 ++++
>   3 files changed, 68 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
> index d5b2612d4ec2..b05f70582788 100644
> --- a/drivers/gpu/drm/i915/display/intel_display.c
> +++ b/drivers/gpu/drm/i915/display/intel_display.c
> @@ -99,6 +99,7 @@
>   #include "intel_hdmi.h"
>   #include "intel_hotplug.h"
>   #include "intel_link_bw.h"
> +#include "intel_lt_phy.h"
>   #include "intel_lvds.h"
>   #include "intel_lvds_regs.h"
>   #include "intel_modeset_setup.h"
> @@ -4963,6 +4964,24 @@ static bool allow_vblank_delay_fastset(const struct intel_crtc_state *old_crtc_s
>   		!intel_crtc_has_type(old_crtc_state, INTEL_OUTPUT_DSI);
>   }
>   
> +static void
> +pipe_config_lt_phy_pll_mismatch(struct drm_printer *p, bool fastset,
> +				const struct intel_crtc *crtc,
> +				const char *name,
> +				const struct intel_lt_phy_pll_state *a,
> +				const struct intel_lt_phy_pll_state *b)
> +{
> +	struct intel_display *display = to_intel_display(crtc);
> +	char *chipname = "LTPHY";
> +
> +	pipe_config_mismatch(p, fastset, crtc, name, chipname);
> +
> +	drm_printf(p, "expected:\n");
> +	intel_lt_phy_dump_hw_state(display, a);
> +	drm_printf(p, "found:\n");
> +	intel_lt_phy_dump_hw_state(display, b);
> +}
> +
>   bool
>   intel_pipe_config_compare(const struct intel_crtc_state *current_config,
>   			  const struct intel_crtc_state *pipe_config,
> @@ -5087,6 +5106,16 @@ intel_pipe_config_compare(const struct intel_crtc_state *current_config,
>   	} \
>   } while (0)
>   
> +#define PIPE_CONF_CHECK_PLL_LT(name) do { \
> +	if (!intel_lt_phy_pll_compare_hw_state(&current_config->name, \
> +					       &pipe_config->name)) { \
> +		pipe_config_lt_phy_pll_mismatch(&p, fastset, crtc, __stringify(name), \
> +						&current_config->name, \
> +						&pipe_config->name); \
> +		ret = false; \
> +	} \
> +} while (0)
> +
>   #define PIPE_CONF_CHECK_TIMINGS(name) do {     \
>   	PIPE_CONF_CHECK_I(name.crtc_hdisplay); \
>   	PIPE_CONF_CHECK_I(name.crtc_htotal); \
> @@ -5311,7 +5340,9 @@ intel_pipe_config_compare(const struct intel_crtc_state *current_config,
>   		PIPE_CONF_CHECK_PLL(dpll_hw_state);
>   
>   	/* FIXME convert MTL+ platforms over to dpll_mgr */
> -	if (DISPLAY_VER(display) >= 14)
> +	if (HAS_LT_PHY(display))
> +		PIPE_CONF_CHECK_PLL_LT(dpll_hw_state.ltpll);
> +	else if (DISPLAY_VER(display) >= 14)
>   		PIPE_CONF_CHECK_PLL_CX0(dpll_hw_state.cx0pll);
>   
>   	PIPE_CONF_CHECK_X(dsi_pll.ctrl);
> diff --git a/drivers/gpu/drm/i915/display/intel_lt_phy.c b/drivers/gpu/drm/i915/display/intel_lt_phy.c
> index f1e41f009bb5..0be4aad0efcc 100644
> --- a/drivers/gpu/drm/i915/display/intel_lt_phy.c
> +++ b/drivers/gpu/drm/i915/display/intel_lt_phy.c
> @@ -1843,6 +1843,36 @@ void intel_lt_phy_set_signal_levels(struct intel_encoder *encoder,
>   	intel_lt_phy_transaction_end(encoder, wakeref);
>   }
>   
> +void intel_lt_phy_dump_hw_state(struct intel_display *display,
> +				const struct intel_lt_phy_pll_state *hw_state)
> +{
> +	int i, j;
> +
> +	drm_dbg_kms(display->drm, "lt_phy_pll_hw_state:\n");
> +	for (i = 0; i < 3; i++) {
> +		drm_dbg_kms(display->drm, "config[%d] = 0x%.4x,\n",
> +			    i, hw_state->config[i]);
> +	}
> +
> +	for (i = 0; i <= 12; i++)
> +		for (j = 3; j >= 0; j--)
> +			drm_dbg_kms(display->drm, "vdr_data[%d][%d] = 0x%.4x,\n",
> +				    i, j, hw_state->data[i][j]);
> +}
> +
> +bool
> +intel_lt_phy_pll_compare_hw_state(const struct intel_lt_phy_pll_state *a,
> +				  const struct intel_lt_phy_pll_state *b)
> +{
> +	if (memcmp(&a->config, &b->config, sizeof(a->config)) != 0)
> +		return false;
> +
> +	if (memcmp(&a->data, &b->data, sizeof(a->data)) != 0)
> +		return false;
> +
> +	return true;
> +}
> +
>   void intel_xe3plpd_pll_enable(struct intel_encoder *encoder,
>   			      const struct intel_crtc_state *crtc_state)
>   {
> diff --git a/drivers/gpu/drm/i915/display/intel_lt_phy.h b/drivers/gpu/drm/i915/display/intel_lt_phy.h
> index 6e67ae78801c..e93e5becc316 100644
> --- a/drivers/gpu/drm/i915/display/intel_lt_phy.h
> +++ b/drivers/gpu/drm/i915/display/intel_lt_phy.h
> @@ -8,6 +8,7 @@
>   
>   #include <linux/types.h>
>   
> +struct intel_display;
>   struct intel_encoder;
>   struct intel_crtc_state;
>   struct intel_lt_phy_pll_state;
> @@ -22,6 +23,11 @@ int intel_lt_phy_calc_port_clock(struct intel_encoder *encoder,
>   				 const struct intel_crtc_state *crtc_state);
>   void intel_lt_phy_set_signal_levels(struct intel_encoder *encoder,
>   				    const struct intel_crtc_state *crtc_state);
> +void intel_lt_phy_dump_hw_state(struct intel_display *display,
> +				const struct intel_lt_phy_pll_state *hw_state);
> +bool
> +intel_lt_phy_pll_compare_hw_state(const struct intel_lt_phy_pll_state *a,
> +				  const struct intel_lt_phy_pll_state *b);
>   void intel_xe3plpd_pll_enable(struct intel_encoder *encoder,
>   			      const struct intel_crtc_state *crtc_state);
>   void intel_xe3plpd_pll_disable(struct intel_encoder *encoder);