Re: [PATCHv2 2/3] fpga: altera-cvp: Preparation for V2 parts.

From: Moritz Fischer
Date: Sun Jul 21 2019 - 20:59:50 EST


Thor,

On Tue, Jul 16, 2019 at 05:48:06PM -0500, thor.thayer@xxxxxxxxxxxxxxx wrote:
> From: Thor Thayer <thor.thayer@xxxxxxxxxxxxxxx>
>
> In preparation for adding newer V2 parts that use a FIFO,
> reorganize altera_cvp_chk_error() and change the write
> function to block based.
> V2 parts have a block size matching the FIFO while older
> V1 parts write a 32 bit word at a time.
>
> Signed-off-by: Thor Thayer <thor.thayer@xxxxxxxxxxxxxxx>
> ---
> v2 Remove inline function declaration
> Reverse Christmas Tree format for local variables
> ---
> drivers/fpga/altera-cvp.c | 72 ++++++++++++++++++++++++++++++-----------------
> 1 file changed, 46 insertions(+), 26 deletions(-)
>
> diff --git a/drivers/fpga/altera-cvp.c b/drivers/fpga/altera-cvp.c
> index b78c90580071..37419d6b9915 100644
> --- a/drivers/fpga/altera-cvp.c
> +++ b/drivers/fpga/altera-cvp.c
> @@ -140,6 +140,41 @@ static int altera_cvp_wait_status(struct altera_cvp_conf *conf, u32 status_mask,
> return -ETIMEDOUT;
> }
>
> +static int altera_cvp_chk_error(struct fpga_manager *mgr, size_t bytes)
> +{
> + struct altera_cvp_conf *conf = mgr->priv;
> + u32 val;
> +
> + /* STEP 10 (optional) - check CVP_CONFIG_ERROR flag */
> + altera_read_config_dword(conf, VSE_CVP_STATUS, &val);
Same as in the other email, why can we ignore return values here. I
think the original code probably did that already.
> + if (val & VSE_CVP_STATUS_CFG_ERR) {
> + dev_err(&mgr->dev, "CVP_CONFIG_ERROR after %zu bytes!\n",
> + bytes);
> + return -EPROTO;
> + }
> + return 0;
> +}
> +
> +static int altera_cvp_send_block(struct altera_cvp_conf *conf,
> + const u32 *data, size_t len)
> +{
> + u32 mask, words = len / sizeof(u32);
> + int i, remainder;
> +
> + for (i = 0; i < words; i++)
> + conf->write_data(conf, *data++);
> +
> + /* write up to 3 trailing bytes, if any */
> + remainder = len % sizeof(u32);
> + if (remainder) {
> + mask = BIT(remainder * 8) - 1;
> + if (mask)
> + conf->write_data(conf, *data & mask);
> + }
> +
> + return 0;
> +}
> +
> static int altera_cvp_teardown(struct fpga_manager *mgr,
> struct fpga_image_info *info)
> {
> @@ -262,39 +297,29 @@ static int altera_cvp_write_init(struct fpga_manager *mgr,
> return 0;
> }
>
> -static inline int altera_cvp_chk_error(struct fpga_manager *mgr, size_t bytes)
> -{
> - struct altera_cvp_conf *conf = mgr->priv;
> - u32 val;
> -
> - /* STEP 10 (optional) - check CVP_CONFIG_ERROR flag */
> - altera_read_config_dword(conf, VSE_CVP_STATUS, &val);
> - if (val & VSE_CVP_STATUS_CFG_ERR) {
> - dev_err(&mgr->dev, "CVP_CONFIG_ERROR after %zu bytes!\n",
> - bytes);
> - return -EPROTO;
> - }
> - return 0;
> -}
> -
> static int altera_cvp_write(struct fpga_manager *mgr, const char *buf,
> size_t count)
> {
> struct altera_cvp_conf *conf = mgr->priv;
> + size_t done, remaining, len;
> const u32 *data;
> - size_t done, remaining;
> int status = 0;
> - u32 mask;
>
> /* STEP 9 - write 32-bit data from RBF file to CVP data register */
> data = (u32 *)buf;
> remaining = count;
> done = 0;
>
> - while (remaining >= 4) {
> - conf->write_data(conf, *data++);
> - done += 4;
> - remaining -= 4;
> + while (remaining) {
> + if (remaining >= sizeof(u32))
> + len = sizeof(u32);
> + else
> + len = remaining;
> +
> + altera_cvp_send_block(conf, data, len);
> + data++;
> + done += len;
> + remaining -= len;
>
> /*
> * STEP 10 (optional) and STEP 11
> @@ -312,11 +337,6 @@ static int altera_cvp_write(struct fpga_manager *mgr, const char *buf,
> }
> }
>
> - /* write up to 3 trailing bytes, if any */
> - mask = BIT(remaining * 8) - 1;
> - if (mask)
> - conf->write_data(conf, *data & mask);
> -
> if (altera_cvp_chkcfg)
> status = altera_cvp_chk_error(mgr, count);
>
> --
> 2.7.4
>
Cheers,
Moritz