KVM: SEV: Do cache maintenance on the source VM during intra-host migrationgrafted

Manually perform cache maintenance on the source VM during intra-host
migration to ensure no stale data is left in CPU caches after the VM is
destroyed.  Because the source VM is "converted" to a non-SEV VM, KVM's
memory reclaim flows won't trigger cache maintenance, e.g. when all guest
memory is reclaimed in response to detaching from the mmu_notifier.

Note, relying on the destination VM to do cache maintenance isn't an option
as KVM doesn't require identical guest memory configurations, i.e. the
source VM may have access to memory that the destination VM does not.
Enforcing equivalent memory configurations is infeasible, as it would
require a *deep* comparison of memslots, e.g. to verify that not only are
the memslot identical, but what the memslots point at is also identical.

Fixes: b56639318bb2 ("KVM: SEV: Add support for SEV intra host migration")
Cc: stable@vger.kernel.org
Reported-by: Stefan Teodorescu <fane@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20260923163721.1584779-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 307 insertions, 0 deletions

diff --git a/sound/soc/codecs/cs40l50-codec.c b/sound/soc/codecs/cs40l50-codec.c
new file mode 100644
index 000000000..676367163
--- /dev/null
+++ b/sound/soc/codecs/cs40l50-codec.c
@@ -0,0 +1,307 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// CS40L50 Advanced Haptic Driver with waveform memory,
+// integrated DSP, and closed-loop algorithms
+//
+// Copyright 2024 Cirrus Logic, Inc.
+//
+// Author: James Ogletree <james.ogletree@cirrus.com>
+
+#include <linux/bitfield.h>
+#include <linux/mfd/cs40l50.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#define CS40L50_REFCLK_INPUT		0x2C04
+#define CS40L50_ASP_CONTROL2		0x4808
+#define CS40L50_ASP_DATA_CONTROL5	0x4840
+
+/* PLL Config */
+#define CS40L50_PLL_REFCLK_BCLK		0x0
+#define CS40L50_PLL_REFCLK_MCLK		0x5
+#define CS40L50_PLL_REEFCLK_MCLK_CFG	0x00
+#define CS40L50_PLL_REFCLK_LOOP_MASK	BIT(11)
+#define CS40L50_PLL_REFCLK_OPEN_LOOP	1
+#define CS40L50_PLL_REFCLK_CLOSED_LOOP	0
+#define CS40L50_PLL_REFCLK_LOOP_SHIFT	11
+#define CS40L50_PLL_REFCLK_FREQ_MASK	GENMASK(10, 5)
+#define CS40L50_PLL_REFCLK_FREQ_SHIFT	5
+#define CS40L50_PLL_REFCLK_SEL_MASK	GENMASK(2, 0)
+#define CS40L50_BCLK_RATIO_DEFAULT	32
+
+/* ASP Config */
+#define CS40L50_ASP_RX_WIDTH_SHIFT	24
+#define CS40L50_ASP_RX_WIDTH_MASK	GENMASK(31, 24)
+#define CS40L50_ASP_RX_WL_MASK		GENMASK(5, 0)
+#define CS40L50_ASP_FSYNC_INV_MASK	BIT(2)
+#define CS40L50_ASP_BCLK_INV_MASK	BIT(6)
+#define CS40L50_ASP_FMT_MASK		GENMASK(10, 8)
+#define CS40L50_ASP_FMT_I2S		0x2
+
+struct cs40l50_pll_config {
+	unsigned int freq;
+	unsigned int cfg;
+};
+
+struct cs40l50_codec {
+	struct device *dev;
+	struct regmap *regmap;
+	unsigned int daifmt;
+	unsigned int bclk_ratio;
+	unsigned int rate;
+};
+
+static const struct cs40l50_pll_config cs40l50_pll_cfg[] = {
+	{ 32768, 0x00 },
+	{ 1536000, 0x1B },
+	{ 3072000, 0x21 },
+	{ 6144000, 0x28 },
+	{ 9600000, 0x30 },
+	{ 12288000, 0x33 },
+};
+
+static int cs40l50_get_clk_config(const unsigned int freq, unsigned int *cfg)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(cs40l50_pll_cfg); i++) {
+		if (cs40l50_pll_cfg[i].freq == freq) {
+			*cfg = cs40l50_pll_cfg[i].cfg;
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static int cs40l50_swap_ext_clk(struct cs40l50_codec *codec, const unsigned int clk_src)
+{
+	unsigned int cfg;
+	int ret;
+
+	switch (clk_src) {
+	case CS40L50_PLL_REFCLK_BCLK:
+		ret = cs40l50_get_clk_config(codec->bclk_ratio * codec->rate, &cfg);
+		if (ret)
+			return ret;
+		break;
+	case CS40L50_PLL_REFCLK_MCLK:
+		cfg = CS40L50_PLL_REEFCLK_MCLK_CFG;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = regmap_update_bits(codec->regmap, CS40L50_REFCLK_INPUT,
+				 CS40L50_PLL_REFCLK_LOOP_MASK,
+				 CS40L50_PLL_REFCLK_OPEN_LOOP <<
+				 CS40L50_PLL_REFCLK_LOOP_SHIFT);
+	if (ret)
+		return ret;
+
+	ret = regmap_update_bits(codec->regmap, CS40L50_REFCLK_INPUT,
+				 CS40L50_PLL_REFCLK_FREQ_MASK |
+				 CS40L50_PLL_REFCLK_SEL_MASK,
+				 (cfg << CS40L50_PLL_REFCLK_FREQ_SHIFT) | clk_src);
+	if (ret)
+		return ret;
+
+	return regmap_update_bits(codec->regmap, CS40L50_REFCLK_INPUT,
+				  CS40L50_PLL_REFCLK_LOOP_MASK,
+				  CS40L50_PLL_REFCLK_CLOSED_LOOP <<
+				  CS40L50_PLL_REFCLK_LOOP_SHIFT);
+}
+
+static int cs40l50_clk_en(struct snd_soc_dapm_widget *w,
+			  struct snd_kcontrol *kcontrol,
+			  int event)
+{
+	struct snd_soc_component *comp = snd_soc_dapm_to_component(w->dapm);
+	struct cs40l50_codec *codec = snd_soc_component_get_drvdata(comp);
+	int ret;
+
+	switch (event) {
+	case SND_SOC_DAPM_POST_PMU:
+		ret = cs40l50_dsp_write(codec->dev, codec->regmap, CS40L50_STOP_PLAYBACK);
+		if (ret)
+			return ret;
+
+		ret = cs40l50_dsp_write(codec->dev, codec->regmap, CS40L50_START_I2S);
+		if (ret)
+			return ret;
+
+		ret = cs40l50_swap_ext_clk(codec, CS40L50_PLL_REFCLK_BCLK);
+		if (ret)
+			return ret;
+		break;
+	case SND_SOC_DAPM_PRE_PMD:
+		ret = cs40l50_swap_ext_clk(codec, CS40L50_PLL_REFCLK_MCLK);
+		if (ret)
+			return ret;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static const struct snd_soc_dapm_widget cs40l50_dapm_widgets[] = {
+	SND_SOC_DAPM_SUPPLY_S("ASP PLL", 0, SND_SOC_NOPM, 0, 0, cs40l50_clk_en,
+			      SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD),
+	SND_SOC_DAPM_AIF_IN("ASPRX1", NULL, 0, SND_SOC_NOPM, 0, 0),
+	SND_SOC_DAPM_AIF_IN("ASPRX2", NULL, 0, SND_SOC_NOPM, 0, 0),
+	SND_SOC_DAPM_OUTPUT("OUT"),
+};
+
+static const struct snd_soc_dapm_route cs40l50_dapm_routes[] = {
+	{ "ASP Playback", NULL, "ASP PLL" },
+	{ "ASPRX1", NULL, "ASP Playback" },
+	{ "ASPRX2", NULL, "ASP Playback" },
+
+	{ "OUT", NULL, "ASPRX1" },
+	{ "OUT", NULL, "ASPRX2" },
+};
+
+static int cs40l50_set_dai_fmt(struct snd_soc_dai *codec_dai, unsigned int fmt)
+{
+	struct cs40l50_codec *codec = snd_soc_component_get_drvdata(codec_dai->component);
+
+	if ((fmt & SND_SOC_DAIFMT_MASTER_MASK) != SND_SOC_DAIFMT_CBC_CFC)
+		return -EINVAL;
+
+	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
+	case SND_SOC_DAIFMT_NB_NF:
+		codec->daifmt = 0;
+		break;
+	case SND_SOC_DAIFMT_NB_IF:
+		codec->daifmt = CS40L50_ASP_FSYNC_INV_MASK;
+		break;
+	case SND_SOC_DAIFMT_IB_NF:
+		codec->daifmt = CS40L50_ASP_BCLK_INV_MASK;
+		break;
+	case SND_SOC_DAIFMT_IB_IF:
+		codec->daifmt = CS40L50_ASP_FSYNC_INV_MASK | CS40L50_ASP_BCLK_INV_MASK;
+		break;
+	default:
+		dev_err(codec->dev, "Invalid clock invert\n");
+		return -EINVAL;
+	}
+
+	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+	case SND_SOC_DAIFMT_I2S:
+		codec->daifmt |= FIELD_PREP(CS40L50_ASP_FMT_MASK, CS40L50_ASP_FMT_I2S);
+		break;
+	default:
+		dev_err(codec->dev, "Unsupported DAI format\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int cs40l50_hw_params(struct snd_pcm_substream *substream,
+			     struct snd_pcm_hw_params *params,
+			     struct snd_soc_dai *dai)
+{
+	struct cs40l50_codec *codec = snd_soc_component_get_drvdata(dai->component);
+	unsigned int asp_rx_wl = params_width(params);
+	int ret;
+
+	codec->rate = params_rate(params);
+
+	ret = regmap_update_bits(codec->regmap, CS40L50_ASP_DATA_CONTROL5,
+				 CS40L50_ASP_RX_WL_MASK, asp_rx_wl);
+	if (ret)
+		return ret;
+
+	codec->daifmt |= (asp_rx_wl << CS40L50_ASP_RX_WIDTH_SHIFT);
+
+	return regmap_update_bits(codec->regmap, CS40L50_ASP_CONTROL2,
+				  CS40L50_ASP_FSYNC_INV_MASK |
+				  CS40L50_ASP_BCLK_INV_MASK |
+				  CS40L50_ASP_FMT_MASK |
+				  CS40L50_ASP_RX_WIDTH_MASK, codec->daifmt);
+}
+
+static int cs40l50_set_dai_bclk_ratio(struct snd_soc_dai *dai, unsigned int ratio)
+{
+	struct cs40l50_codec *codec = snd_soc_component_get_drvdata(dai->component);
+
+	codec->bclk_ratio = ratio;
+
+	return 0;
+}
+
+static const struct snd_soc_dai_ops cs40l50_dai_ops = {
+	.set_fmt = cs40l50_set_dai_fmt,
+	.set_bclk_ratio = cs40l50_set_dai_bclk_ratio,
+	.hw_params = cs40l50_hw_params,
+};
+
+static struct snd_soc_dai_driver cs40l50_dai[] = {
+	{
+		.name = "cs40l50-pcm",
+		.id = 0,
+		.playback = {
+			.stream_name = "ASP Playback",
+			.channels_min = 1,
+			.channels_max = 2,
+			.rates = SNDRV_PCM_RATE_48000,
+			.formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE,
+		},
+		.ops = &cs40l50_dai_ops,
+	},
+};
+
+static int cs40l50_codec_probe(struct snd_soc_component *component)
+{
+	struct cs40l50_codec *codec = snd_soc_component_get_drvdata(component);
+
+	codec->bclk_ratio = CS40L50_BCLK_RATIO_DEFAULT;
+
+	return 0;
+}
+
+static const struct snd_soc_component_driver soc_codec_dev_cs40l50 = {
+	.probe = cs40l50_codec_probe,
+	.dapm_widgets = cs40l50_dapm_widgets,
+	.num_dapm_widgets = ARRAY_SIZE(cs40l50_dapm_widgets),
+	.dapm_routes = cs40l50_dapm_routes,
+	.num_dapm_routes = ARRAY_SIZE(cs40l50_dapm_routes),
+};
+
+static int cs40l50_codec_driver_probe(struct platform_device *pdev)
+{
+	struct cs40l50 *cs40l50 = dev_get_drvdata(pdev->dev.parent);
+	struct cs40l50_codec *codec;
+
+	codec = devm_kzalloc(&pdev->dev, sizeof(*codec), GFP_KERNEL);
+	if (!codec)
+		return -ENOMEM;
+
+	codec->regmap = cs40l50->regmap;
+	codec->dev = &pdev->dev;
+
+	return devm_snd_soc_register_component(&pdev->dev, &soc_codec_dev_cs40l50,
+					       cs40l50_dai, ARRAY_SIZE(cs40l50_dai));
+}
+
+static const struct platform_device_id cs40l50_id[] = {
+	{ .name = "cs40l50-codec" },
+	{ }
+};
+MODULE_DEVICE_TABLE(platform, cs40l50_id);
+
+static struct platform_driver cs40l50_codec_driver = {
+	.probe = cs40l50_codec_driver_probe,
+	.id_table = cs40l50_id,
+	.driver = {
+		.name = "cs40l50-codec",
+	},
+};
+module_platform_driver(cs40l50_codec_driver);
+
+MODULE_DESCRIPTION("ASoC CS40L50 driver");
+MODULE_AUTHOR("James Ogletree <james.ogletree@cirrus.com>");
+MODULE_LICENSE("GPL");