Re: [PATCH AUTOSEL 5.17 34/49] spi: cadence-quadspi: fix protocol setup for non-1-1-X operations

[Matthias Schiffer]

Hi Mark,

what's your plan regarding this patch and the other patch I sent [1]? I
think there has been some confusion regarding which solution we want to
backport to stable kernels (well, at least I'm confused...)

I'm fine with this patch getting backported, but in that case [1]
doesn't make sense anymore (in fact I expected this patch to be dropped
for now when I submitted [1], due to Pratyush Yadav's concerns).

Regards,
Matthias


[1] https://patchwork.kernel.org/project/spi-devel-general/patch/20220406132832.199777-1-matthias.schiffer@xxxxxxxxxxxxxxx/



On Mon, 2022-04-11 at 20:43 -0400, Sasha Levin wrote:
> From: Matthias Schiffer <matthias.schiffer@xxxxxxxxxxxxxxx>
> 
> [ Upstream commit 97e4827d775faa9a32b5e1a97959c69dd77d17a3 ]
> 
> cqspi_set_protocol() only set the data width, but ignored the command
> and address width (except for 8-8-8 DTR ops), leading to corruption
> of
> all transfers using 1-X-X or X-X-X ops. Fix by setting the other two
> widths as well.
> 
> While we're at it, simplify the code a bit by replacing the
> CQSPI_INST_TYPE_* constants with ilog2().
> 
> Tested on a TI AM64x with a Macronix MX25U51245G QSPI flash with 1-4-
> 4
> read and write operations.
> 
> Signed-off-by: Matthias Schiffer <matthias.schiffer@xxxxxxxxxxxxxxx>
> Link: 
> https://lore.kernel.org/r/20220331110819.133392-1-matthias.schiffer@xxxxxxxxxxxxxxx
> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
>  drivers/spi/spi-cadence-quadspi.c | 46 ++++++++---------------------
> --
>  1 file changed, 12 insertions(+), 34 deletions(-)
> 
> diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-
> cadence-quadspi.c
> index b808c94641fa..75f356041138 100644
> --- a/drivers/spi/spi-cadence-quadspi.c
> +++ b/drivers/spi/spi-cadence-quadspi.c
> @@ -19,6 +19,7 @@
>  #include <linux/iopoll.h>
>  #include <linux/jiffies.h>
>  #include <linux/kernel.h>
> +#include <linux/log2.h>
>  #include <linux/module.h>
>  #include <linux/of_device.h>
>  #include <linux/of.h>
> @@ -102,12 +103,6 @@ struct cqspi_driver_platdata {
>  #define CQSPI_TIMEOUT_MS			500
>  #define CQSPI_READ_TIMEOUT_MS			10
>  
> -/* Instruction type */
> -#define CQSPI_INST_TYPE_SINGLE			0
> -#define CQSPI_INST_TYPE_DUAL			1
> -#define CQSPI_INST_TYPE_QUAD			2
> -#define CQSPI_INST_TYPE_OCTAL			3
> -
>  #define CQSPI_DUMMY_CLKS_PER_BYTE		8
>  #define CQSPI_DUMMY_BYTES_MAX			4
>  #define CQSPI_DUMMY_CLKS_MAX			31
> @@ -376,10 +371,6 @@ static unsigned int cqspi_calc_dummy(const
> struct spi_mem_op *op, bool dtr)
>  static int cqspi_set_protocol(struct cqspi_flash_pdata *f_pdata,
>  			      const struct spi_mem_op *op)
>  {
> -	f_pdata->inst_width = CQSPI_INST_TYPE_SINGLE;
> -	f_pdata->addr_width = CQSPI_INST_TYPE_SINGLE;
> -	f_pdata->data_width = CQSPI_INST_TYPE_SINGLE;
> -
>  	/*
>  	 * For an op to be DTR, cmd phase along with every other non-
> empty
>  	 * phase should have dtr field set to 1. If an op phase has
> zero
> @@ -389,32 +380,23 @@ static int cqspi_set_protocol(struct
> cqspi_flash_pdata *f_pdata,
>  		       (!op->addr.nbytes || op->addr.dtr) &&
>  		       (!op->data.nbytes || op->data.dtr);
>  
> -	switch (op->data.buswidth) {
> -	case 0:
> -		break;
> -	case 1:
> -		f_pdata->data_width = CQSPI_INST_TYPE_SINGLE;
> -		break;
> -	case 2:
> -		f_pdata->data_width = CQSPI_INST_TYPE_DUAL;
> -		break;
> -	case 4:
> -		f_pdata->data_width = CQSPI_INST_TYPE_QUAD;
> -		break;
> -	case 8:
> -		f_pdata->data_width = CQSPI_INST_TYPE_OCTAL;
> -		break;
> -	default:
> -		return -EINVAL;
> -	}
> +	f_pdata->inst_width = 0;
> +	if (op->cmd.buswidth)
> +		f_pdata->inst_width = ilog2(op->cmd.buswidth);
> +
> +	f_pdata->addr_width = 0;
> +	if (op->addr.buswidth)
> +		f_pdata->addr_width = ilog2(op->addr.buswidth);
> +
> +	f_pdata->data_width = 0;
> +	if (op->data.buswidth)
> +		f_pdata->data_width = ilog2(op->data.buswidth);
>  
>  	/* Right now we only support 8-8-8 DTR mode. */
>  	if (f_pdata->dtr) {
>  		switch (op->cmd.buswidth) {
>  		case 0:
> -			break;
>  		case 8:
> -			f_pdata->inst_width = CQSPI_INST_TYPE_OCTAL;
>  			break;
>  		default:
>  			return -EINVAL;
> @@ -422,9 +404,7 @@ static int cqspi_set_protocol(struct
> cqspi_flash_pdata *f_pdata,
>  
>  		switch (op->addr.buswidth) {
>  		case 0:
> -			break;
>  		case 8:
> -			f_pdata->addr_width = CQSPI_INST_TYPE_OCTAL;
>  			break;
>  		default:
>  			return -EINVAL;
> @@ -432,9 +412,7 @@ static int cqspi_set_protocol(struct
> cqspi_flash_pdata *f_pdata,
>  
>  		switch (op->data.buswidth) {
>  		case 0:
> -			break;
>  		case 8:
> -			f_pdata->data_width = CQSPI_INST_TYPE_OCTAL;
>  			break;
>  		default:
>  			return -EINVAL;