From: Gustavo Sousa <gustavo.sousa@intel.com>
To: intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org
Cc: Gustavo Sousa <gustavo.sousa@intel.com>,
Jani Nikula <jani.nikula@intel.com>,
Matt Roper <matthew.d.roper@intel.com>,
Rodrigo Vivi <rodrigo.vivi@intel.com>
Subject: [PATCH v2 1/4] drm/i915/bw: Extract platform-specific parameters
Date: Mon, 11 May 2026 13:30:56 -0300 [thread overview]
Message-ID: <20260511-separate-platform-from-diplay-ip-specific-bw-params-v2-1-e762cb8662da@intel.com> (raw)
In-Reply-To: <20260511-separate-platform-from-diplay-ip-specific-bw-params-v2-0-e762cb8662da@intel.com>
We got confirmation from the hardware team that the bandwidth parameters
deprogbwlimit and derating are platform-specific and not tied to the
display IP. As such, let's make sure that we use platform checks for
those.
The rest of the members of struct intel_sa_info are tied to the display
IP and we will deal with them as a follow-up.
v2:
- Use good old if-ladder instead of weird-looking pattern "assign ret,
check platform, then return ret". (Jani, Matt)
- Have a single call site for get_platform_bw_params() and pass the
result as parameter to the *_get_bw_info() functions. (Jani)
- Avoid using "plat" as abbreviation for "platform". (Jani)
- s/_plat_bw_params/_bw_params/, since all of the instances are
prefixed with platform names. (Jani)
- s/struct intel_platform_bw_params/struct intel_soc_bw_params/.
(Matt)
- Do not return a default value; prefer to return NULL and
intentionally cause a NULL pointer dereference if a platform is
missing. (Gustavo)
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
---
drivers/gpu/drm/i915/display/intel_bw.c | 161 ++++++++++++++++++++++----------
1 file changed, 113 insertions(+), 48 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_bw.c b/drivers/gpu/drm/i915/display/intel_bw.c
index 9c3a9bbb49f6..cf6756b8ae52 100644
--- a/drivers/gpu/drm/i915/display/intel_bw.c
+++ b/drivers/gpu/drm/i915/display/intel_bw.c
@@ -372,81 +372,147 @@ static int icl_sagv_max_dclk(const struct intel_qgv_info *qi)
return dclk;
}
+struct intel_soc_bw_params {
+ u8 deprogbwlimit;
+ u8 derating;
+};
+
+static const struct intel_soc_bw_params icl_bw_params = {
+ .deprogbwlimit = 25,
+ .derating = 10,
+};
+
+static const struct intel_soc_bw_params tgl_bw_params = {
+ .deprogbwlimit = 34,
+ .derating = 10,
+};
+
+static const struct intel_soc_bw_params rkl_bw_params = {
+ .deprogbwlimit = 20,
+ .derating = 10,
+};
+
+static const struct intel_soc_bw_params adl_s_bw_params = {
+ .deprogbwlimit = 38,
+ .derating = 10,
+};
+
+static const struct intel_soc_bw_params adl_p_bw_params = {
+ .deprogbwlimit = 38,
+ .derating = 20,
+};
+
+static const struct intel_soc_bw_params bmg_bw_params = {
+ .deprogbwlimit = 53,
+ .derating = 30,
+};
+
+static const struct intel_soc_bw_params bmg_ecc_bw_params = {
+ .deprogbwlimit = 53,
+ .derating = 45,
+};
+
+static const struct intel_soc_bw_params ptl_bw_params = {
+ .deprogbwlimit = 65,
+ .derating = 10,
+};
+
+static const struct intel_soc_bw_params wcl_bw_params = {
+ .deprogbwlimit = 22,
+ .derating = 10,
+};
+
+static const struct intel_soc_bw_params *get_soc_bw_params(struct intel_display *display)
+{
+ if (display->platform.dgfx) {
+ if (display->platform.dg1) {
+ return &tgl_bw_params;
+ } else if (display->platform.battlemage) {
+ const struct dram_info *dram_info = intel_dram_info(display);
+
+ if (dram_info->type == INTEL_DRAM_GDDR_ECC)
+ return &bmg_ecc_bw_params;
+ else
+ return &bmg_bw_params;
+ }
+ } else {
+ if (display->platform.icelake ||
+ display->platform.jasperlake ||
+ display->platform.elkhartlake) {
+ return &icl_bw_params;
+ } else if (display->platform.tigerlake) {
+ return &tgl_bw_params;
+ } else if (display->platform.rocketlake) {
+ return &rkl_bw_params;
+ } else if (display->platform.alderlake_s) {
+ return &adl_s_bw_params;
+ } else if (display->platform.alderlake_p) {
+ return &adl_p_bw_params;
+ } else if (display->platform.meteorlake ||
+ display->platform.lunarlake) {
+ return &adl_s_bw_params;
+ } else if (display->platform.pantherlake ||
+ display->platform.novalake) {
+ if (display->platform.pantherlake_wildcatlake)
+ return &wcl_bw_params;
+ else
+ return &ptl_bw_params;
+ }
+ }
+
+ drm_WARN(display->drm, 1, "Platform-specific bandwidth parameters not found!\n");
+
+ return NULL;
+}
+
struct intel_sa_info {
u16 displayrtids;
- u8 deburst, deprogbwlimit, derating;
+ u8 deburst;
};
static const struct intel_sa_info icl_sa_info = {
.deburst = 8,
- .deprogbwlimit = 25, /* GB/s */
.displayrtids = 128,
- .derating = 10,
};
static const struct intel_sa_info tgl_sa_info = {
.deburst = 16,
- .deprogbwlimit = 34, /* GB/s */
.displayrtids = 256,
- .derating = 10,
};
static const struct intel_sa_info rkl_sa_info = {
.deburst = 8,
- .deprogbwlimit = 20, /* GB/s */
.displayrtids = 128,
- .derating = 10,
};
static const struct intel_sa_info adls_sa_info = {
.deburst = 16,
- .deprogbwlimit = 38, /* GB/s */
.displayrtids = 256,
- .derating = 10,
};
static const struct intel_sa_info adlp_sa_info = {
.deburst = 16,
- .deprogbwlimit = 38, /* GB/s */
.displayrtids = 256,
- .derating = 20,
};
static const struct intel_sa_info mtl_sa_info = {
.deburst = 32,
- .deprogbwlimit = 38, /* GB/s */
.displayrtids = 256,
- .derating = 10,
-};
-
-static const struct intel_sa_info xe2_hpd_sa_info = {
- .derating = 30,
- .deprogbwlimit = 53,
- /* Other values not used by simplified algorithm */
-};
-
-static const struct intel_sa_info xe2_hpd_ecc_sa_info = {
- .derating = 45,
- .deprogbwlimit = 53,
- /* Other values not used by simplified algorithm */
};
static const struct intel_sa_info xe3lpd_sa_info = {
.deburst = 32,
- .deprogbwlimit = 65, /* GB/s */
.displayrtids = 256,
- .derating = 10,
};
static const struct intel_sa_info xe3lpd_3002_sa_info = {
.deburst = 32,
- .deprogbwlimit = 22, /* GB/s */
.displayrtids = 256,
- .derating = 10,
};
static int icl_get_bw_info(struct intel_display *display,
const struct dram_info *dram_info,
+ const struct intel_soc_bw_params *soc_bw_params,
const struct intel_sa_info *sa)
{
struct intel_qgv_info qi = {};
@@ -466,7 +532,7 @@ static int icl_get_bw_info(struct intel_display *display,
}
dclk_max = icl_sagv_max_dclk(&qi);
- maxdebw = min(sa->deprogbwlimit * 1000, dclk_max * 16 * 6 / 10);
+ maxdebw = min(soc_bw_params->deprogbwlimit * 1000, dclk_max * 16 * 6 / 10);
ipqdepth = min(ipqdepthpch, sa->displayrtids / num_channels);
qi.deinterleave = DIV_ROUND_UP(num_channels, is_y_tile ? 4 : 2);
@@ -496,7 +562,7 @@ static int icl_get_bw_info(struct intel_display *display,
bw = DIV_ROUND_UP(sp->dclk * clpchgroup * 32 * num_channels, ct);
bi->deratedbw[j] = min(maxdebw,
- bw * (100 - sa->derating) / 100);
+ bw * (100 - soc_bw_params->derating) / 100);
drm_dbg_kms(display->drm,
"BW%d / QGV %d: num_planes=%d deratedbw=%u\n",
@@ -518,6 +584,7 @@ static int icl_get_bw_info(struct intel_display *display,
static int tgl_get_bw_info(struct intel_display *display,
const struct dram_info *dram_info,
+ const struct intel_soc_bw_params *soc_bw_params,
const struct intel_sa_info *sa)
{
struct intel_qgv_info qi = {};
@@ -554,7 +621,7 @@ static int tgl_get_bw_info(struct intel_display *display,
dclk_max = icl_sagv_max_dclk(&qi);
peakbw = num_channels * DIV_ROUND_UP(qi.channel_width, 8) * dclk_max;
- maxdebw = min(sa->deprogbwlimit * 1000, peakbw * DEPROGBWPCLIMIT / 100);
+ maxdebw = min(soc_bw_params->deprogbwlimit * 1000, peakbw * DEPROGBWPCLIMIT / 100);
ipqdepth = min(ipqdepthpch, sa->displayrtids / num_channels);
/*
@@ -599,7 +666,7 @@ static int tgl_get_bw_info(struct intel_display *display,
bw = DIV_ROUND_UP(sp->dclk * clpchgroup * 32 * num_channels, ct);
bi->deratedbw[j] = min(maxdebw,
- bw * (100 - sa->derating) / 100);
+ bw * (100 - soc_bw_params->derating) / 100);
bi->peakbw[j] = DIV_ROUND_CLOSEST(sp->dclk *
num_channels *
qi.channel_width, 8);
@@ -661,7 +728,7 @@ static void dg2_get_bw_info(struct intel_display *display)
static int xe2_hpd_get_bw_info(struct intel_display *display,
const struct dram_info *dram_info,
- const struct intel_sa_info *sa)
+ const struct intel_soc_bw_params *soc_bw_params)
{
struct intel_qgv_info qi = {};
int num_channels = dram_info->num_channels;
@@ -676,14 +743,14 @@ static int xe2_hpd_get_bw_info(struct intel_display *display,
}
peakbw = num_channels * qi.channel_width / 8 * icl_sagv_max_dclk(&qi);
- maxdebw = min(sa->deprogbwlimit * 1000, peakbw * DEPROGBWPCLIMIT / 10);
+ maxdebw = min(soc_bw_params->deprogbwlimit * 1000, peakbw * DEPROGBWPCLIMIT / 10);
for (i = 0; i < qi.num_points; i++) {
const struct intel_qgv_point *point = &qi.points[i];
int bw = num_channels * (qi.channel_width / 8) * point->dclk;
display->bw.max[0].deratedbw[i] =
- min(maxdebw, (100 - sa->derating) * bw / 100);
+ min(maxdebw, (100 - soc_bw_params->derating) * bw / 100);
display->bw.max[0].peakbw[i] = bw;
drm_dbg_kms(display->drm, "QGV %d: deratedbw=%u peakbw: %u\n",
@@ -792,6 +859,7 @@ static unsigned int icl_qgv_bw(struct intel_display *display,
void intel_bw_init_hw(struct intel_display *display)
{
const struct dram_info *dram_info = intel_dram_info(display);
+ const struct intel_soc_bw_params *soc_bw_params = get_soc_bw_params(display);
if (!HAS_DISPLAY(display))
return;
@@ -807,28 +875,25 @@ void intel_bw_init_hw(struct intel_display *display)
if (DISPLAY_VER(display) >= 30) {
if (DISPLAY_VERx100(display) == 3002)
- tgl_get_bw_info(display, dram_info, &xe3lpd_3002_sa_info);
+ tgl_get_bw_info(display, dram_info, soc_bw_params, &xe3lpd_3002_sa_info);
else
- tgl_get_bw_info(display, dram_info, &xe3lpd_sa_info);
+ tgl_get_bw_info(display, dram_info, soc_bw_params, &xe3lpd_sa_info);
} else if (DISPLAY_VERx100(display) >= 1401 && display->platform.dgfx) {
- if (dram_info->type == INTEL_DRAM_GDDR_ECC)
- xe2_hpd_get_bw_info(display, dram_info, &xe2_hpd_ecc_sa_info);
- else
- xe2_hpd_get_bw_info(display, dram_info, &xe2_hpd_sa_info);
+ xe2_hpd_get_bw_info(display, dram_info, soc_bw_params);
} else if (DISPLAY_VER(display) >= 14) {
- tgl_get_bw_info(display, dram_info, &mtl_sa_info);
+ tgl_get_bw_info(display, dram_info, soc_bw_params, &mtl_sa_info);
} else if (display->platform.dg2) {
dg2_get_bw_info(display);
} else if (display->platform.alderlake_p) {
- tgl_get_bw_info(display, dram_info, &adlp_sa_info);
+ tgl_get_bw_info(display, dram_info, soc_bw_params, &adlp_sa_info);
} else if (display->platform.alderlake_s) {
- tgl_get_bw_info(display, dram_info, &adls_sa_info);
+ tgl_get_bw_info(display, dram_info, soc_bw_params, &adls_sa_info);
} else if (display->platform.rocketlake) {
- tgl_get_bw_info(display, dram_info, &rkl_sa_info);
+ tgl_get_bw_info(display, dram_info, soc_bw_params, &rkl_sa_info);
} else if (DISPLAY_VER(display) == 12) {
- tgl_get_bw_info(display, dram_info, &tgl_sa_info);
+ tgl_get_bw_info(display, dram_info, soc_bw_params, &tgl_sa_info);
} else if (DISPLAY_VER(display) == 11) {
- icl_get_bw_info(display, dram_info, &icl_sa_info);
+ icl_get_bw_info(display, dram_info, soc_bw_params, &icl_sa_info);
}
}
--
2.53.0
next prev parent reply other threads:[~2026-05-11 16:31 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-05-11 16:30 [PATCH v2 0/4] drm/i915/bw: Split bandwidth params into platform- and display-IP-specific structs Gustavo Sousa
2026-05-11 16:30 ` Gustavo Sousa [this message]
2026-05-11 22:38 ` [PATCH v2 1/4] drm/i915/bw: Extract platform-specific parameters Matt Roper
2026-05-12 8:18 ` Jani Nikula
2026-05-12 13:14 ` Gustavo Sousa
2026-05-12 13:05 ` Gustavo Sousa
2026-05-11 16:30 ` [PATCH v2 2/4] drm/i915/bw: Deduplicate intel_sa_info instances Gustavo Sousa
2026-05-11 22:43 ` Matt Roper
2026-05-11 16:30 ` [PATCH v2 3/4] drm/i915/bw: Rename struct intel_sa_info to intel_display_bw_params Gustavo Sousa
2026-05-11 22:44 ` Matt Roper
2026-05-11 16:30 ` [PATCH v2 4/4] drm/i915/bw: Extract get_display_bw_params() Gustavo Sousa
2026-05-11 22:49 ` Matt Roper
2026-05-12 8:22 ` Jani Nikula
2026-05-12 13:33 ` Gustavo Sousa
2026-05-12 13:30 ` Gustavo Sousa
2026-05-11 22:15 ` ✓ CI.KUnit: success for drm/i915/bw: Split bandwidth params into platform- and display-IP-specific structs Patchwork
2026-05-11 23:29 ` ✓ Xe.CI.BAT: " Patchwork
2026-05-12 2:07 ` ✗ Xe.CI.FULL: failure " Patchwork
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