Unverified Commit 7726e498 authored by Richard Fitzgerald's avatar Richard Fitzgerald Committed by Mark Brown
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ASoC: wm_adsp: Improve handling of raw byte streams 



As the register map is 16-bit or 32-bit big-endian, the 24-bit
DSP words appear padded and with the bytes swapped. When reading a
raw stream of bytes, the pad bytes must be removed and the data bytes
swapped back to their original order.

The previous implementation of this assumed that the be32_to_cpu() in
wm_adsp_read_data_block() would swap back to little-endian. But this is
obviously only true on a little-endian CPU. It also made two walks
through the data, once to endian-swap and again to strip the pad bytes.

This patch re-works the code so that the endian-swap and unpad are done
together in a single walk, and it is not dependent on the endianness of
the CPU. The data_word_size argument to wm_adsp_remove_padding() has been
dropped because currently this is always 3.

Signed-off-by: default avatarRichard Fitzgerald <rf@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20201216112512.26503-1-rf@opensource.cirrus.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent a9830fc3

sound/soc/codecs/wm_adsp.c

+30 −25
Original line number Diff line number Diff line
@@ -3664,12 +3664,12 @@ int wm_adsp_compr_get_caps(struct snd_soc_component *component, 
}

EXPORT_SYMBOL_GPL(wm_adsp_compr_get_caps);



static int wm_adsp_read_data_block(struct wm_adsp *dsp, int mem_type,

static int wm_adsp_read_raw_data_block(struct wm_adsp *dsp, int mem_type,

				       unsigned int mem_addr,

				   unsigned int num_words, u32 *data)

				       unsigned int num_words, __be32 *data)

{

	struct wm_adsp_region const *mem = wm_adsp_find_region(dsp, mem_type);

	unsigned int i, reg;

	unsigned int reg;

	int ret;



	if (!mem)
@@ -3682,16 +3682,22 @@ static int wm_adsp_read_data_block(struct wm_adsp *dsp, int mem_type, 
	if (ret < 0)

		return ret;



	for (i = 0; i < num_words; ++i)

		data[i] = be32_to_cpu(data[i]) & 0x00ffffffu;



	return 0;

}



static inline int wm_adsp_read_data_word(struct wm_adsp *dsp, int mem_type,

					 unsigned int mem_addr, u32 *data)

{

	return wm_adsp_read_data_block(dsp, mem_type, mem_addr, 1, data);

	__be32 raw;

	int ret;



	ret = wm_adsp_read_raw_data_block(dsp, mem_type, mem_addr, 1, &raw);

	if (ret)

		return ret;



	*data = be32_to_cpu(raw) & 0x00ffffffu;



	return 0;

}



static int wm_adsp_write_data_word(struct wm_adsp *dsp, int mem_type,
@@ -3724,18 +3730,22 @@ static inline int wm_adsp_buffer_write(struct wm_adsp_compr_buf *buf, 
				       buf->host_buf_ptr + field_offset, data);

}



static void wm_adsp_remove_padding(u32 *buf, int nwords, int data_word_size)

static void wm_adsp_remove_padding(u32 *buf, int nwords)

{

	u8 *pack_in = (u8 *)buf;

	const __be32 *pack_in = (__be32 *)buf;

	u8 *pack_out = (u8 *)buf;

	int i, j;

	int i;



	/* Remove the padding bytes from the data read from the DSP */

	/*

	 * DSP words from the register map have pad bytes and the data bytes

	 * are in swapped order. This swaps back to the original little-endian

	 * order and strips the pad bytes.

	 */

	for (i = 0; i < nwords; i++) {

		for (j = 0; j < data_word_size; j++)

			*pack_out++ = *pack_in++;



		pack_in += sizeof(*buf) - data_word_size;

		u32 word = be32_to_cpu(*pack_in++);

		*pack_out++ = (u8)word;

		*pack_out++ = (u8)(word >> 8);

		*pack_out++ = (u8)(word >> 16);

	}

}
@@ -3919,12 +3929,7 @@ static int wm_adsp_buffer_parse_coeff(struct wm_coeff_ctl *ctl) 
		return -EINVAL;

	}



	for (i = 0; i < ARRAY_SIZE(coeff_v1.name); i++)

		coeff_v1.name[i] = be32_to_cpu(coeff_v1.name[i]);



	wm_adsp_remove_padding((u32 *)&coeff_v1.name,

			       ARRAY_SIZE(coeff_v1.name),

			       WM_ADSP_DATA_WORD_SIZE);

	wm_adsp_remove_padding((u32 *)&coeff_v1.name, ARRAY_SIZE(coeff_v1.name));



	buf->name = kasprintf(GFP_KERNEL, "%s-dsp-%s", ctl->dsp->part,

			      (char *)&coeff_v1.name);
@@ -4263,12 +4268,12 @@ static int wm_adsp_buffer_capture_block(struct wm_adsp_compr *compr, int target) 
		return 0;



	/* Read data from DSP */

	ret = wm_adsp_read_data_block(buf->dsp, mem_type, adsp_addr,

	ret = wm_adsp_read_raw_data_block(buf->dsp, mem_type, adsp_addr,

					  nwords, compr->raw_buf);

	if (ret < 0)

		return ret;



	wm_adsp_remove_padding(compr->raw_buf, nwords, WM_ADSP_DATA_WORD_SIZE);

	wm_adsp_remove_padding(compr->raw_buf, nwords);



	/* update read index to account for words read */

	buf->read_index += nwords;