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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/gpu/drm/amd/amdgpu/amdgpu_afmt.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu_afmt.c')
-rw-r--r--drivers/gpu/drm/amd/amdgpu/amdgpu_afmt.c105
1 files changed, 105 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_afmt.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_afmt.c
new file mode 100644
index 000000000..a4d65973b
--- /dev/null
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_afmt.c
@@ -0,0 +1,105 @@
+/*
+ * Copyright 2008 Advanced Micro Devices, Inc.
+ * Copyright 2008 Red Hat Inc.
+ * Copyright 2009 Christian König.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: Christian König
+ */
+#include <linux/hdmi.h>
+#include <linux/gcd.h>
+
+#include <drm/amdgpu_drm.h>
+#include "amdgpu.h"
+
+static const struct amdgpu_afmt_acr amdgpu_afmt_predefined_acr[] = {
+ /* 32kHz 44.1kHz 48kHz */
+ /* Clock N CTS N CTS N CTS */
+ { 25175, 4096, 25175, 28224, 125875, 6144, 25175 }, /* 25,20/1.001 MHz */
+ { 25200, 4096, 25200, 6272, 28000, 6144, 25200 }, /* 25.20 MHz */
+ { 27000, 4096, 27000, 6272, 30000, 6144, 27000 }, /* 27.00 MHz */
+ { 27027, 4096, 27027, 6272, 30030, 6144, 27027 }, /* 27.00*1.001 MHz */
+ { 54000, 4096, 54000, 6272, 60000, 6144, 54000 }, /* 54.00 MHz */
+ { 54054, 4096, 54054, 6272, 60060, 6144, 54054 }, /* 54.00*1.001 MHz */
+ { 74176, 4096, 74176, 5733, 75335, 6144, 74176 }, /* 74.25/1.001 MHz */
+ { 74250, 4096, 74250, 6272, 82500, 6144, 74250 }, /* 74.25 MHz */
+ { 148352, 4096, 148352, 5733, 150670, 6144, 148352 }, /* 148.50/1.001 MHz */
+ { 148500, 4096, 148500, 6272, 165000, 6144, 148500 }, /* 148.50 MHz */
+};
+
+
+/*
+ * calculate CTS and N values if they are not found in the table
+ */
+static void amdgpu_afmt_calc_cts(uint32_t clock, int *CTS, int *N, int freq)
+{
+ int n, cts;
+ unsigned long div, mul;
+
+ /* Safe, but overly large values */
+ n = 128 * freq;
+ cts = clock * 1000;
+
+ /* Smallest valid fraction */
+ div = gcd(n, cts);
+
+ n /= div;
+ cts /= div;
+
+ /*
+ * The optimal N is 128*freq/1000. Calculate the closest larger
+ * value that doesn't truncate any bits.
+ */
+ mul = ((128*freq/1000) + (n-1))/n;
+
+ n *= mul;
+ cts *= mul;
+
+ /* Check that we are in spec (not always possible) */
+ if (n < (128*freq/1500))
+ pr_warn("Calculated ACR N value is too small. You may experience audio problems.\n");
+ if (n > (128*freq/300))
+ pr_warn("Calculated ACR N value is too large. You may experience audio problems.\n");
+
+ *N = n;
+ *CTS = cts;
+
+ DRM_DEBUG("Calculated ACR timing N=%d CTS=%d for frequency %d\n",
+ *N, *CTS, freq);
+}
+
+struct amdgpu_afmt_acr amdgpu_afmt_acr(uint32_t clock)
+{
+ struct amdgpu_afmt_acr res;
+ u8 i;
+
+ /* Precalculated values for common clocks */
+ for (i = 0; i < ARRAY_SIZE(amdgpu_afmt_predefined_acr); i++) {
+ if (amdgpu_afmt_predefined_acr[i].clock == clock)
+ return amdgpu_afmt_predefined_acr[i];
+ }
+
+ /* And odd clocks get manually calculated */
+ amdgpu_afmt_calc_cts(clock, &res.cts_32khz, &res.n_32khz, 32000);
+ amdgpu_afmt_calc_cts(clock, &res.cts_44_1khz, &res.n_44_1khz, 44100);
+ amdgpu_afmt_calc_cts(clock, &res.cts_48khz, &res.n_48khz, 48000);
+
+ return res;
+}