Commit 34796ce4 authored by Gustavo Sousa's avatar Gustavo Sousa Committed by Matt Roper
Browse files

drm/i915/xe3lpd: Use DMC wakelock by default 



Although Bspec doesn't explicitly mentions that, as of Xe3_LPD, using
DMC wakelock is the officially recommended way of accessing registers
that would be off during DC5/DC6 and the legacy method (where the DMC
intercepts MMIO to wake up the hardware) is to be avoided.

As such, update the driver to use the DMC wakelock by default starting
with Xe3_LPD. Since the feature is somewhat new to the driver, also
allow disabling it via a module parameter for debugging purposes.

For that, make the existing parameter allow values -1 (per-chip
default), 0 (disabled) and 1 (enabled), similarly to what is done for
other parameters.

v2:
  - Describe -1 in the same area where 0 and 1 are described. (Luca)

Reviewed-by: default avatarLuca Coelho <luciano.coelho@intel.com>
Signed-off-by: default avatarGustavo Sousa <gustavo.sousa@intel.com>
Signed-off-by: default avatarMatt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241108130218.24125-16-gustavo.sousa@intel.com
parent c01e78a9

drivers/gpu/drm/i915/display/intel_display_params.c

+3 −3
Original line number Diff line number Diff line
@@ -123,10 +123,10 @@ intel_display_param_named_unsafe(enable_psr2_sel_fetch, bool, 0400, 
	"(0=disabled, 1=enabled) "

	"Default: 1");



intel_display_param_named_unsafe(enable_dmc_wl, bool, 0400,

intel_display_param_named_unsafe(enable_dmc_wl, int, 0400,

	"Enable DMC wakelock "

	"(0=disabled, 1=enabled) "

	"Default: 0");

	"(-1=use per-chip default, 0=disabled, 1=enabled) "

	"Default: -1");



__maybe_unused

static void _param_print_bool(struct drm_printer *p, const char *driver_name,

drivers/gpu/drm/i915/display/intel_display_params.h

+1 −1
Original line number Diff line number Diff line
@@ -47,7 +47,7 @@ struct drm_printer; 
	param(int, enable_psr, -1, 0600) \

	param(bool, psr_safest_params, false, 0400) \

	param(bool, enable_psr2_sel_fetch, true, 0400) \

	param(bool, enable_dmc_wl, false, 0400) \

	param(int, enable_dmc_wl, -1, 0400) \



#define MEMBER(T, member, ...) T member;

struct intel_display_params {

drivers/gpu/drm/i915/display/intel_dmc_wl.c

+5 −1
Original line number Diff line number Diff line
@@ -270,7 +270,11 @@ static bool __intel_dmc_wl_supported(struct intel_display *display) 
static void intel_dmc_wl_sanitize_param(struct intel_display *display)

{

	if (!HAS_DMC_WAKELOCK(display))

		display->params.enable_dmc_wl = false;

		display->params.enable_dmc_wl = 0;

	else if (display->params.enable_dmc_wl >= 0)

		display->params.enable_dmc_wl = !!display->params.enable_dmc_wl;

	else

		display->params.enable_dmc_wl = DISPLAY_VER(display) >= 30;



	drm_dbg_kms(display->drm, "Sanitized enable_dmc_wl value: %d\n",

		    display->params.enable_dmc_wl);