| Message ID | 20221201134845.4055907-2-rf@opensource.cirrus.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | soundwire: cadence: Fix oversized FIFO size define | expand |
On 12/1/22 07:48, Richard Fitzgerald wrote: > The command FIFOs are 8 entries long, so change CDNS_MCP_CMD_LEN to 8. > > CDNS_MCP_CMD_LEN was originally 32, which would lead to cdns_xfer_msg() > writing up to 32 commands into the FIFO, so any message longer than 8 > commands would fail. The change is correct for all instances of SoundWire on Intel platforms. That said, maybe we should capture that the Cadence IP can handle 4/8/16/32 entries - this is a hardware configuration option. We should also mention that so far we have not sent multiple commands so far so the code is only broken when grouping commands. Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> > > Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com> > Fixes: 2f52a5177caa ("soundwire: cdns: Add cadence library") > --- > drivers/soundwire/cadence_master.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c > index a1de363eba3f..27699f341f2c 100644 > --- a/drivers/soundwire/cadence_master.c > +++ b/drivers/soundwire/cadence_master.c > @@ -127,7 +127,8 @@ MODULE_PARM_DESC(cdns_mcp_int_mask, "Cadence MCP IntMask"); > > #define CDNS_MCP_CMD_BASE 0x80 > #define CDNS_MCP_RESP_BASE 0x80 > -#define CDNS_MCP_CMD_LEN 0x20 > +/* FIFO can hold 8 commands */ > +#define CDNS_MCP_CMD_LEN 8 > #define CDNS_MCP_CMD_WORD_LEN 0x4 > > #define CDNS_MCP_CMD_SSP_TAG BIT(31)
diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index a1de363eba3f..27699f341f2c 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -127,7 +127,8 @@ MODULE_PARM_DESC(cdns_mcp_int_mask, "Cadence MCP IntMask"); #define CDNS_MCP_CMD_BASE 0x80 #define CDNS_MCP_RESP_BASE 0x80 -#define CDNS_MCP_CMD_LEN 0x20 +/* FIFO can hold 8 commands */ +#define CDNS_MCP_CMD_LEN 8 #define CDNS_MCP_CMD_WORD_LEN 0x4 #define CDNS_MCP_CMD_SSP_TAG BIT(31)
The command FIFOs are 8 entries long, so change CDNS_MCP_CMD_LEN to 8. CDNS_MCP_CMD_LEN was originally 32, which would lead to cdns_xfer_msg() writing up to 32 commands into the FIFO, so any message longer than 8 commands would fail. Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com> Fixes: 2f52a5177caa ("soundwire: cdns: Add cadence library") --- drivers/soundwire/cadence_master.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)