mirror of
https://github.com/torvalds/linux.git
synced 2026-10-28 09:35:02 +01:00
drm/bridge: dw-hdmi-qp: use drm_hdmi_acr_get_n_cts() helper for audio N/CTS
dw_hdmi_qp_set_sample_rate() open-coded its own N and CTS lookup tables and search/compute helpers, but it lacked the out-of-table CTS fallback needed by strict HDMI sinks at TMDS rates not in the table. The original LG G3 OLED audio mute (linux-rockchip 070633) was caused by dw_hdmi_qp_find_cts() returning 0 at 185.625 MHz, leaving AUDPKT_ACR_CTS_OVR_EN clear and falling back to the controller's internal CTS auto-measurement, which produces incorrect timing on the wire at out-of-table rates. The shared drm_hdmi_acr_get_n_cts() helper in drivers/gpu/drm/display/drm_hdmi_helper.c already implements the correct behaviour: it has the HDMI 1.4b spec N/CTS tables, and for TMDS rates not in the table it computes CTS = (TMDS * N) / (128 * Fs) inline (the canonical HDMI spec formula). It is already used by drivers/gpu/drm/msm/hdmi/hdmi_audio.c. Convert dw_hdmi_qp_set_sample_rate() to call the helper. This removes ~200 lines of open-coded tables and search functions (dw_hdmi_qp_find_n, _compute_n, _find_cts, _audio_math_diff, _match_tmds_n_table, common_tmds_n_table[], common_tmds_cts_table[]) and fixes the strict-sink audio mute as a side effect of using the helper's complete N+CTS path. Tested on R76S (RK3576) running Linux 7.0.1, against the LG G3 OLED (the sink that originally reported the mute in linux-rockchip 070633) at four TMDS rates spanning HDMI 1.4 and HDMI 2.0: TMDS Mode Audio with v3 148.5 MHz 1080p60 8-bit plays 185.625 MHz 1080p60 10-bit plays 297 MHz 1080p100 8-bit plays 594 MHz 3840p60 8-bit plays Without this change, the LG G3 mutes audio at 185.625, 297, and 594 MHz (every rate outside dw-hdmi-qp's open-coded CTS table, which contained only 148.5 MHz and below). With this change, drm_hdmi_acr_get_n_cts() supplies the correct CTS at every rate -- table-canonical at 148.5 / 297 / 594 MHz, and computed via the HDMI 1.4b formula at 185.625 MHz. The 148.5 MHz row is a regression check confirming the in-table path is unchanged. The Kogan KALED43XU9210STA (a permissive HDMI 2.0 sink that plays audio at all rates with or without this change) was used as a no-regression control: audio plays at 594 MHz with v3 loaded. The open-coded N table in dw-hdmi-qp included optimised N values for some TMDS rates that are not in the helper's table (e.g. various non-CEA rates between 28-162 MHz). For those rates the helper's fallback returns N = 128 * Fs / 1000, which is the same value dw_hdmi_qp_compute_n() returned when no table optimisation was needed; no audio regression has been observed at the rates tested above. Reported-by: Simon Wright <simon@symple.nz> Closes: https://lore.kernel.org/linux-rockchip/ME3P282MB21960D9D68BFF520316BDFCEA83E2@ME3P282MB2196.AUSP282.PROD.OUTLOOK.COM/ Suggested-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com> Suggested-by: Jonas Karlman <jonas@kwiboo.se> Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Simon Wright <simon@symple.nz> Tested-by: Igor Paunovic <royalnet026@gmail.com> # RK3588 Orange Pi 5 Plus, both HDMI controllers Tested-by: Christian Hewitt <christianshewitt@gmail.com> Reviewed-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com> Tested-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com> Signed-off-by: Heiko Stuebner <heiko@sntech.de> Link: https://patch.msgid.link/86fcf349-0a7a-4618-9001-612371b0f71b@symple.nz
This commit is contained in:
Simon Wright
Heiko Stuebner
parent
28fcfb9c20
commit
a9f09b5ea0
|
|
@ -40,88 +40,6 @@
|
|||
|
||||
#define SCRAMB_POLL_DELAY_MS 3000
|
||||
|
||||
/*
|
||||
* Unless otherwise noted, entries in this table are 100% optimization.
|
||||
* Values can be obtained from dw_hdmi_qp_compute_n() but that function is
|
||||
* slow so we pre-compute values we expect to see.
|
||||
*
|
||||
* The values for TMDS 25175, 25200, 27000, 54000, 74250 and 148500 kHz are
|
||||
* the recommended N values specified in the Audio chapter of the HDMI
|
||||
* specification.
|
||||
*/
|
||||
static const struct dw_hdmi_audio_tmds_n {
|
||||
unsigned long tmds;
|
||||
unsigned int n_32k;
|
||||
unsigned int n_44k1;
|
||||
unsigned int n_48k;
|
||||
} common_tmds_n_table[] = {
|
||||
{ .tmds = 25175000, .n_32k = 4576, .n_44k1 = 7007, .n_48k = 6864, },
|
||||
{ .tmds = 25200000, .n_32k = 4096, .n_44k1 = 6272, .n_48k = 6144, },
|
||||
{ .tmds = 27000000, .n_32k = 4096, .n_44k1 = 6272, .n_48k = 6144, },
|
||||
{ .tmds = 28320000, .n_32k = 4096, .n_44k1 = 5586, .n_48k = 6144, },
|
||||
{ .tmds = 30240000, .n_32k = 4096, .n_44k1 = 5642, .n_48k = 6144, },
|
||||
{ .tmds = 31500000, .n_32k = 4096, .n_44k1 = 5600, .n_48k = 6144, },
|
||||
{ .tmds = 32000000, .n_32k = 4096, .n_44k1 = 5733, .n_48k = 6144, },
|
||||
{ .tmds = 33750000, .n_32k = 4096, .n_44k1 = 6272, .n_48k = 6144, },
|
||||
{ .tmds = 36000000, .n_32k = 4096, .n_44k1 = 5684, .n_48k = 6144, },
|
||||
{ .tmds = 40000000, .n_32k = 4096, .n_44k1 = 5733, .n_48k = 6144, },
|
||||
{ .tmds = 49500000, .n_32k = 4096, .n_44k1 = 5488, .n_48k = 6144, },
|
||||
{ .tmds = 50000000, .n_32k = 4096, .n_44k1 = 5292, .n_48k = 6144, },
|
||||
{ .tmds = 54000000, .n_32k = 4096, .n_44k1 = 6272, .n_48k = 6144, },
|
||||
{ .tmds = 65000000, .n_32k = 4096, .n_44k1 = 7056, .n_48k = 6144, },
|
||||
{ .tmds = 68250000, .n_32k = 4096, .n_44k1 = 5376, .n_48k = 6144, },
|
||||
{ .tmds = 71000000, .n_32k = 4096, .n_44k1 = 7056, .n_48k = 6144, },
|
||||
{ .tmds = 72000000, .n_32k = 4096, .n_44k1 = 5635, .n_48k = 6144, },
|
||||
{ .tmds = 73250000, .n_32k = 11648, .n_44k1 = 14112, .n_48k = 6144, },
|
||||
{ .tmds = 74250000, .n_32k = 4096, .n_44k1 = 6272, .n_48k = 6144, },
|
||||
{ .tmds = 75000000, .n_32k = 4096, .n_44k1 = 5880, .n_48k = 6144, },
|
||||
{ .tmds = 78750000, .n_32k = 4096, .n_44k1 = 5600, .n_48k = 6144, },
|
||||
{ .tmds = 78800000, .n_32k = 4096, .n_44k1 = 5292, .n_48k = 6144, },
|
||||
{ .tmds = 79500000, .n_32k = 4096, .n_44k1 = 4704, .n_48k = 6144, },
|
||||
{ .tmds = 83500000, .n_32k = 4096, .n_44k1 = 7056, .n_48k = 6144, },
|
||||
{ .tmds = 85500000, .n_32k = 4096, .n_44k1 = 5488, .n_48k = 6144, },
|
||||
{ .tmds = 88750000, .n_32k = 4096, .n_44k1 = 14112, .n_48k = 6144, },
|
||||
{ .tmds = 97750000, .n_32k = 4096, .n_44k1 = 14112, .n_48k = 6144, },
|
||||
{ .tmds = 101000000, .n_32k = 4096, .n_44k1 = 7056, .n_48k = 6144, },
|
||||
{ .tmds = 106500000, .n_32k = 4096, .n_44k1 = 4704, .n_48k = 6144, },
|
||||
{ .tmds = 108000000, .n_32k = 4096, .n_44k1 = 5684, .n_48k = 6144, },
|
||||
{ .tmds = 115500000, .n_32k = 4096, .n_44k1 = 5712, .n_48k = 6144, },
|
||||
{ .tmds = 119000000, .n_32k = 4096, .n_44k1 = 5544, .n_48k = 6144, },
|
||||
{ .tmds = 135000000, .n_32k = 4096, .n_44k1 = 5488, .n_48k = 6144, },
|
||||
{ .tmds = 146250000, .n_32k = 11648, .n_44k1 = 6272, .n_48k = 6144, },
|
||||
{ .tmds = 148500000, .n_32k = 4096, .n_44k1 = 6272, .n_48k = 6144, },
|
||||
{ .tmds = 154000000, .n_32k = 4096, .n_44k1 = 5544, .n_48k = 6144, },
|
||||
{ .tmds = 162000000, .n_32k = 4096, .n_44k1 = 5684, .n_48k = 6144, },
|
||||
|
||||
/* For 297 MHz+ HDMI spec have some other rule for setting N */
|
||||
{ .tmds = 297000000, .n_32k = 3073, .n_44k1 = 4704, .n_48k = 5120, },
|
||||
{ .tmds = 594000000, .n_32k = 3073, .n_44k1 = 9408, .n_48k = 10240,},
|
||||
|
||||
/* End of table */
|
||||
{ .tmds = 0, .n_32k = 0, .n_44k1 = 0, .n_48k = 0, },
|
||||
};
|
||||
|
||||
/*
|
||||
* These are the CTS values as recommended in the Audio chapter of the HDMI
|
||||
* specification.
|
||||
*/
|
||||
static const struct dw_hdmi_audio_tmds_cts {
|
||||
unsigned long tmds;
|
||||
unsigned int cts_32k;
|
||||
unsigned int cts_44k1;
|
||||
unsigned int cts_48k;
|
||||
} common_tmds_cts_table[] = {
|
||||
{ .tmds = 25175000, .cts_32k = 28125, .cts_44k1 = 31250, .cts_48k = 28125, },
|
||||
{ .tmds = 25200000, .cts_32k = 25200, .cts_44k1 = 28000, .cts_48k = 25200, },
|
||||
{ .tmds = 27000000, .cts_32k = 27000, .cts_44k1 = 30000, .cts_48k = 27000, },
|
||||
{ .tmds = 54000000, .cts_32k = 54000, .cts_44k1 = 60000, .cts_48k = 54000, },
|
||||
{ .tmds = 74250000, .cts_32k = 74250, .cts_44k1 = 82500, .cts_48k = 74250, },
|
||||
{ .tmds = 148500000, .cts_32k = 148500, .cts_44k1 = 165000, .cts_48k = 148500, },
|
||||
|
||||
/* End of table */
|
||||
{ .tmds = 0, .cts_32k = 0, .cts_44k1 = 0, .cts_48k = 0, },
|
||||
};
|
||||
|
||||
struct dw_hdmi_qp_i2c {
|
||||
struct i2c_adapter adap;
|
||||
|
||||
|
|
@ -213,130 +131,6 @@ static void dw_hdmi_qp_set_cts_n(struct dw_hdmi_qp *hdmi, unsigned int cts,
|
|||
AUDPKT_ACR_CONTROL1);
|
||||
}
|
||||
|
||||
static int dw_hdmi_qp_match_tmds_n_table(struct dw_hdmi_qp *hdmi,
|
||||
unsigned long pixel_clk,
|
||||
unsigned long freq)
|
||||
{
|
||||
const struct dw_hdmi_audio_tmds_n *tmds_n = NULL;
|
||||
int i;
|
||||
|
||||
for (i = 0; common_tmds_n_table[i].tmds != 0; i++) {
|
||||
if (pixel_clk == common_tmds_n_table[i].tmds) {
|
||||
tmds_n = &common_tmds_n_table[i];
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
if (!tmds_n)
|
||||
return -ENOENT;
|
||||
|
||||
switch (freq) {
|
||||
case 32000:
|
||||
return tmds_n->n_32k;
|
||||
case 44100:
|
||||
case 88200:
|
||||
case 176400:
|
||||
return (freq / 44100) * tmds_n->n_44k1;
|
||||
case 48000:
|
||||
case 96000:
|
||||
case 192000:
|
||||
return (freq / 48000) * tmds_n->n_48k;
|
||||
default:
|
||||
return -ENOENT;
|
||||
}
|
||||
}
|
||||
|
||||
static u32 dw_hdmi_qp_audio_math_diff(unsigned int freq, unsigned int n,
|
||||
unsigned int pixel_clk)
|
||||
{
|
||||
u64 cts = mul_u32_u32(pixel_clk, n);
|
||||
|
||||
return do_div(cts, 128 * freq);
|
||||
}
|
||||
|
||||
static unsigned int dw_hdmi_qp_compute_n(struct dw_hdmi_qp *hdmi,
|
||||
unsigned long pixel_clk,
|
||||
unsigned long freq)
|
||||
{
|
||||
unsigned int min_n = DIV_ROUND_UP((128 * freq), 1500);
|
||||
unsigned int max_n = (128 * freq) / 300;
|
||||
unsigned int ideal_n = (128 * freq) / 1000;
|
||||
unsigned int best_n_distance = ideal_n;
|
||||
unsigned int best_n = 0;
|
||||
u64 best_diff = U64_MAX;
|
||||
int n;
|
||||
|
||||
/* If the ideal N could satisfy the audio math, then just take it */
|
||||
if (dw_hdmi_qp_audio_math_diff(freq, ideal_n, pixel_clk) == 0)
|
||||
return ideal_n;
|
||||
|
||||
for (n = min_n; n <= max_n; n++) {
|
||||
u64 diff = dw_hdmi_qp_audio_math_diff(freq, n, pixel_clk);
|
||||
|
||||
if (diff < best_diff ||
|
||||
(diff == best_diff && abs(n - ideal_n) < best_n_distance)) {
|
||||
best_n = n;
|
||||
best_diff = diff;
|
||||
best_n_distance = abs(best_n - ideal_n);
|
||||
}
|
||||
|
||||
/*
|
||||
* The best N already satisfy the audio math, and also be
|
||||
* the closest value to ideal N, so just cut the loop.
|
||||
*/
|
||||
if (best_diff == 0 && (abs(n - ideal_n) > best_n_distance))
|
||||
break;
|
||||
}
|
||||
|
||||
return best_n;
|
||||
}
|
||||
|
||||
static unsigned int dw_hdmi_qp_find_n(struct dw_hdmi_qp *hdmi, unsigned long pixel_clk,
|
||||
unsigned long sample_rate)
|
||||
{
|
||||
int n = dw_hdmi_qp_match_tmds_n_table(hdmi, pixel_clk, sample_rate);
|
||||
|
||||
if (n > 0)
|
||||
return n;
|
||||
|
||||
dev_warn(hdmi->dev, "Rate %lu missing; compute N dynamically\n",
|
||||
pixel_clk);
|
||||
|
||||
return dw_hdmi_qp_compute_n(hdmi, pixel_clk, sample_rate);
|
||||
}
|
||||
|
||||
static unsigned int dw_hdmi_qp_find_cts(struct dw_hdmi_qp *hdmi, unsigned long pixel_clk,
|
||||
unsigned long sample_rate)
|
||||
{
|
||||
const struct dw_hdmi_audio_tmds_cts *tmds_cts = NULL;
|
||||
int i;
|
||||
|
||||
for (i = 0; common_tmds_cts_table[i].tmds != 0; i++) {
|
||||
if (pixel_clk == common_tmds_cts_table[i].tmds) {
|
||||
tmds_cts = &common_tmds_cts_table[i];
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
if (!tmds_cts)
|
||||
return 0;
|
||||
|
||||
switch (sample_rate) {
|
||||
case 32000:
|
||||
return tmds_cts->cts_32k;
|
||||
case 44100:
|
||||
case 88200:
|
||||
case 176400:
|
||||
return tmds_cts->cts_44k1;
|
||||
case 48000:
|
||||
case 96000:
|
||||
case 192000:
|
||||
return tmds_cts->cts_48k;
|
||||
default:
|
||||
return -ENOENT;
|
||||
}
|
||||
}
|
||||
|
||||
static void dw_hdmi_qp_set_audio_interface(struct dw_hdmi_qp *hdmi,
|
||||
struct hdmi_codec_daifmt *fmt,
|
||||
struct hdmi_codec_params *hparms)
|
||||
|
|
@ -456,8 +250,7 @@ static void dw_hdmi_qp_set_sample_rate(struct dw_hdmi_qp *hdmi, unsigned long lo
|
|||
{
|
||||
unsigned int n, cts;
|
||||
|
||||
n = dw_hdmi_qp_find_n(hdmi, tmds_char_rate, sample_rate);
|
||||
cts = dw_hdmi_qp_find_cts(hdmi, tmds_char_rate, sample_rate);
|
||||
drm_hdmi_acr_get_n_cts(tmds_char_rate, sample_rate, &n, &cts);
|
||||
|
||||
dw_hdmi_qp_set_cts_n(hdmi, cts, n);
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user