Add dummy read after each block enable, to workaround SRAM write missing bytes issue.
Signed-off-by: Jie Yang yang.jie@intel.com --- sound/soc/intel/sst-haswell-dsp.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)
diff --git a/sound/soc/intel/sst-haswell-dsp.c b/sound/soc/intel/sst-haswell-dsp.c index f4276fb..cc58b31 100644 --- a/sound/soc/intel/sst-haswell-dsp.c +++ b/sound/soc/intel/sst-haswell-dsp.c @@ -381,6 +381,17 @@ static u32 hsw_block_get_bit(struct sst_mem_block *block) return bit; }
+/*dummy read a SRAM block.*/ +static void sst_mem_block_dummy_read(struct sst_mem_block *block) +{ + u32 size; + u8 tmp_buf[4]; + struct sst_dsp *sst = block->dsp; + + size = block->size > 4 ? 4 : block->size; + memcpy_fromio(tmp_buf, sst->addr.lpe + block->offset, size); +} + /* enable 32kB memory block - locks held by caller */ static int hsw_block_enable(struct sst_mem_block *block) { @@ -400,6 +411,8 @@ static int hsw_block_enable(struct sst_mem_block *block) /* wait 18 DSP clock ticks */ udelay(10);
+ /*add a dummy read before the SRAM block is written, otherwise the writing may miss bytes sometimes.*/ + sst_mem_block_dummy_read(block); return 0; }