[PATCH 0/2] ASoC: cs35l56: Don't patch firmware that is already patched

[PATCH 0/2] ASoC: cs35l56: Don't patch firmware that is already patched

[Richard Fitzgerald]

Use the FIRMWARE_MISSING flag in the CS35L56 to determine whether it is
safe to download a firmware patch.

Richard Fitzgerald (2):
  ASoC: wm_adsp: Support powering-up DSP without trying to load firmware
  ASoC: cs35l56: Don't overwrite a patched firmware

 sound/soc/codecs/cs35l56.c | 19 ++++++++++++++++---
 sound/soc/codecs/wm_adsp.c | 16 +++++++++-------
 sound/soc/codecs/wm_adsp.h |  2 +-
 3 files changed, 26 insertions(+), 11 deletions(-)

-- 
2.30.2

[PATCH 1/2] ASoC: wm_adsp: Support powering-up DSP without trying to load firmware

[Richard Fitzgerald]

Add a flag to wm_adsp_power_up() that indicates whether it should attempt
to find and load firmware files.

This is to support DSPs that have built-in firmware that may already have
been patched (for example, by the BIOS). In that case the patch must not
be overwritten because that could corrupt the running firmware.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
 sound/soc/codecs/cs35l56.c |  4 ++--
 sound/soc/codecs/wm_adsp.c | 16 +++++++++-------
 sound/soc/codecs/wm_adsp.h |  2 +-
 3 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/sound/soc/codecs/cs35l56.c b/sound/soc/codecs/cs35l56.c
index 80e7fddae926..98cfcae554af 100644
--- a/sound/soc/codecs/cs35l56.c
+++ b/sound/soc/codecs/cs35l56.c
@@ -656,7 +656,7 @@ static void cs35l56_secure_patch(struct cs35l56_private *cs35l56)
 	int ret;
 
 	/* Use wm_adsp to load and apply the firmware patch and coefficient files */
-	ret = wm_adsp_power_up(&cs35l56->dsp);
+	ret = wm_adsp_power_up(&cs35l56->dsp, true);
 	if (ret)
 		dev_dbg(cs35l56->base.dev, "%s: wm_adsp_power_up ret %d\n", __func__, ret);
 	else
@@ -686,7 +686,7 @@ static void cs35l56_patch(struct cs35l56_private *cs35l56)
 		goto err;
 
 	/* Use wm_adsp to load and apply the firmware patch and coefficient files */
-	ret = wm_adsp_power_up(&cs35l56->dsp);
+	ret = wm_adsp_power_up(&cs35l56->dsp, true);
 	if (ret) {
 		dev_dbg(cs35l56->base.dev, "%s: wm_adsp_power_up ret %d\n", __func__, ret);
 		goto err;
diff --git a/sound/soc/codecs/wm_adsp.c b/sound/soc/codecs/wm_adsp.c
index 13f500fa9a5f..6fc34f41b175 100644
--- a/sound/soc/codecs/wm_adsp.c
+++ b/sound/soc/codecs/wm_adsp.c
@@ -998,7 +998,7 @@ int wm_adsp2_preloader_put(struct snd_kcontrol *kcontrol,
 }
 EXPORT_SYMBOL_GPL(wm_adsp2_preloader_put);
 
-int wm_adsp_power_up(struct wm_adsp *dsp)
+int wm_adsp_power_up(struct wm_adsp *dsp, bool load_firmware)
 {
 	int ret = 0;
 	char *wmfw_filename = NULL;
@@ -1006,11 +1006,13 @@ int wm_adsp_power_up(struct wm_adsp *dsp)
 	char *coeff_filename = NULL;
 	const struct firmware *coeff_firmware = NULL;
 
-	ret = wm_adsp_request_firmware_files(dsp,
-					     &wmfw_firmware, &wmfw_filename,
-					     &coeff_firmware, &coeff_filename);
-	if (ret)
-		return ret;
+	if (load_firmware) {
+		ret = wm_adsp_request_firmware_files(dsp,
+						     &wmfw_firmware, &wmfw_filename,
+						     &coeff_firmware, &coeff_filename);
+		if (ret)
+			return ret;
+	}
 
 	ret = cs_dsp_power_up(&dsp->cs_dsp,
 			      wmfw_firmware, wmfw_filename,
@@ -1037,7 +1039,7 @@ static void wm_adsp_boot_work(struct work_struct *work)
 					   struct wm_adsp,
 					   boot_work);
 
-	wm_adsp_power_up(dsp);
+	wm_adsp_power_up(dsp, true);
 }
 
 int wm_adsp_early_event(struct snd_soc_dapm_widget *w,
diff --git a/sound/soc/codecs/wm_adsp.h b/sound/soc/codecs/wm_adsp.h
index 3044f964ac14..067d807a7ca8 100644
--- a/sound/soc/codecs/wm_adsp.h
+++ b/sound/soc/codecs/wm_adsp.h
@@ -91,7 +91,7 @@ int wm_adsp1_event(struct snd_soc_dapm_widget *w,
 int wm_adsp_early_event(struct snd_soc_dapm_widget *w,
 			struct snd_kcontrol *kcontrol, int event);
 
-int wm_adsp_power_up(struct wm_adsp *dsp);
+int wm_adsp_power_up(struct wm_adsp *dsp, bool load_firmware);
 void wm_adsp_power_down(struct wm_adsp *dsp);
 
 irqreturn_t wm_adsp2_bus_error(int irq, void *data);
-- 
2.30.2

[PATCH 2/2] ASoC: cs35l56: Don't overwrite a patched firmware

[Richard Fitzgerald]

Only attempt to download wmfw/bin files to a non-secured part if
it reports FIRMWARE_MISSING. If FIRMWARE_MISSING is false the
firmware has already been patched and overwriting the patch could
corrupt the running firmware.

For a secured part the wmfw/bin can be downloaded even if
FIRMWARE_MISSING is false, because they will only patch tunings.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
 sound/soc/codecs/cs35l56.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/sound/soc/codecs/cs35l56.c b/sound/soc/codecs/cs35l56.c
index 98cfcae554af..3a9ec8724cc1 100644
--- a/sound/soc/codecs/cs35l56.c
+++ b/sound/soc/codecs/cs35l56.c
@@ -665,8 +665,17 @@ static void cs35l56_secure_patch(struct cs35l56_private *cs35l56)
 
 static void cs35l56_patch(struct cs35l56_private *cs35l56)
 {
+	unsigned int firmware_missing;
 	int ret;
 
+	ret = regmap_read(cs35l56->base.regmap, CS35L56_PROTECTION_STATUS, &firmware_missing);
+	if (ret) {
+		dev_err(cs35l56->base.dev, "Failed to read PROTECTION_STATUS: %d\n", ret);
+		return;
+	}
+
+	firmware_missing &= CS35L56_FIRMWARE_MISSING;
+
 	/*
 	 * Disable SoundWire interrupts to prevent race with IRQ work.
 	 * Setting sdw_irq_no_unmask prevents the handler re-enabling
@@ -685,8 +694,12 @@ static void cs35l56_patch(struct cs35l56_private *cs35l56)
 	if (ret)
 		goto err;
 
-	/* Use wm_adsp to load and apply the firmware patch and coefficient files */
-	ret = wm_adsp_power_up(&cs35l56->dsp, true);
+	/*
+	 * Use wm_adsp to load and apply the firmware patch and coefficient files,
+	 * but only if firmware is missing. If firmware is already patched just
+	 * power-up wm_adsp without downloading firmware.
+	 */
+	ret = wm_adsp_power_up(&cs35l56->dsp, !!firmware_missing);
 	if (ret) {
 		dev_dbg(cs35l56->base.dev, "%s: wm_adsp_power_up ret %d\n", __func__, ret);
 		goto err;
-- 
2.30.2

Re: [PATCH 0/2] ASoC: cs35l56: Don't patch firmware that is already patched

[Mark Brown]

On Tue, 15 Aug 2023 13:48:24 +0100, Richard Fitzgerald wrote:
> Use the FIRMWARE_MISSING flag in the CS35L56 to determine whether it is
> safe to download a firmware patch.
> 
> Richard Fitzgerald (2):
>   ASoC: wm_adsp: Support powering-up DSP without trying to load firmware
>   ASoC: cs35l56: Don't overwrite a patched firmware
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next

Thanks!

[1/2] ASoC: wm_adsp: Support powering-up DSP without trying to load firmware
      commit: 62ddad4238a0250aa9cedade127c39aac9d26d45
[2/2] ASoC: cs35l56: Don't overwrite a patched firmware
      commit: 67bd793ba5e0984ecb7ee4407c2f79d159e305ff

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark