[Skiboot] [PATCH 07/11] libflash/mbox-flash: Use BMC suggested timeout value

[Samuel Mendoza-Jonas]

On Thu, 2017-06-29 at 22:39 +1000, Cyril Bur wrote:
> Signed-off-by: Cyril Bur <cyril.bur at au1.ibm.com>
> ---
>  libflash/mbox-flash.c | 37 ++++++++++++++++++++++++++-----------
>  1 file changed, 26 insertions(+), 11 deletions(-)
> 
> diff --git a/libflash/mbox-flash.c b/libflash/mbox-flash.c
> index 999f663c..2a7321f4 100644
> --- a/libflash/mbox-flash.c
> +++ b/libflash/mbox-flash.c
> @@ -50,6 +50,7 @@ struct lpc_window {
>  
>  struct mbox_flash_data {
>  	int version;
> +	uint16_t timeout;
>  	uint32_t shift;
>  	struct lpc_window read;
>  	struct lpc_window write;
> @@ -286,7 +287,12 @@ static int mbox_flash_ack(struct mbox_flash_data *mbox_flash, uint8_t reg)
>  	/* Clear this first so msg_send() doesn't freak out */
>  	mbox_flash->reboot = false;
>  
> -	rc = msg_send(mbox_flash, &msg, MBOX_DEFAULT_TIMEOUT);
> +	/*
> +	 * Use a lower timeout - there is strong evidence to suggest the
> +	 * BMC won't respond, don't waste time spinning here just have the
> +	 * high levels retry when the BMC might be back
> +	 */
> +	rc = msg_send(mbox_flash, &msg, 3);

Ah this answers my earlier question then - BMC's are gross as always.

>  
>  	/* Still need to deal with it, we've only acked it now. */
>  	mbox_flash->reboot = true;
> @@ -340,6 +346,9 @@ static void mbox_flash_do_get_mbox_info(struct mbox_flash_data *mbox_flash,
>  		mbox_flash->write.size = blocks_to_bytes(mbox_flash, msg_get_u16(msg, 3));
>  	} else { /* V2 compatible */
>  		mbox_flash->shift = msg_get_u8(msg, 5);
> +		mbox_flash->timeout = msg_get_u16(msg, 6);
> +		if (mbox_flash->timeout == 0)
> +			mbox_flash->timeout = MBOX_DEFAULT_TIMEOUT;
>  	}
>  	/* Callers will handle the case where the version is not known
>  	 *
> @@ -472,13 +481,13 @@ static int mbox_flash_mark_write(struct mbox_flash_data *mbox_flash,
>  		msg_put_u16(&msg, 2, end - start); /* Total Length */
>  	}
>  
> -	rc = msg_send(mbox_flash, &msg, MBOX_DEFAULT_TIMEOUT);
> +	rc = msg_send(mbox_flash, &msg, mbox_flash->timeout);
>  	if (rc) {
>  		prlog(PR_ERR, "Failed to enqueue/send BMC MBOX message\n");
>  		return rc;
>  	}
>  
> -	rc = wait_for_bmc(mbox_flash, MBOX_DEFAULT_TIMEOUT);
> +	rc = wait_for_bmc(mbox_flash, mbox_flash->timeout);
>  	if (rc)
>  		prlog(PR_ERR, "Error waiting for BMC\n");
>  
> @@ -519,13 +528,13 @@ static int mbox_flash_flush(struct mbox_flash_data *mbox_flash)
>  		return FLASH_ERR_DEVICE_GONE;
>  	}
>  
> -	rc = msg_send(mbox_flash, &msg, MBOX_DEFAULT_TIMEOUT);
> +	rc = msg_send(mbox_flash, &msg, mbox_flash->timeout);
>  	if (rc) {
>  		prlog(PR_ERR, "Failed to enqueue/send BMC MBOX message\n");
>  		return rc;
>  	}
>  
> -	rc = wait_for_bmc(mbox_flash, MBOX_DEFAULT_TIMEOUT);
> +	rc = wait_for_bmc(mbox_flash, mbox_flash->timeout);
>  	if (rc)
>  		prlog(PR_ERR, "Error waiting for BMC\n");
>  
> @@ -568,7 +577,7 @@ static int mbox_window_move(struct mbox_flash_data *mbox_flash,
>  	win->cur_pos = pos & ~mbox_flash_mask(mbox_flash);
>  
>  	msg_put_u16(&msg, 0, bytes_to_blocks(mbox_flash, pos));
> -	rc = msg_send(mbox_flash, &msg, MBOX_DEFAULT_TIMEOUT);
> +	rc = msg_send(mbox_flash, &msg, mbox_flash->timeout);
>  	if (rc) {
>  		prlog(PR_ERR, "Failed to enqueue/send BMC MBOX message\n");
>  		return rc;
> @@ -577,7 +586,7 @@ static int mbox_window_move(struct mbox_flash_data *mbox_flash,
>  	mbox_flash->read.open = false;
>  	mbox_flash->write.open = false;
>  
> -	rc = wait_for_bmc(mbox_flash, MBOX_DEFAULT_TIMEOUT);
> +	rc = wait_for_bmc(mbox_flash, mbox_flash->timeout);
>  	if (rc) {
>  		prlog(PR_ERR, "Error waiting for BMC\n");
>  		return rc;
> @@ -725,13 +734,13 @@ static int mbox_flash_get_info(struct blocklevel_device *bl, const char **name,
>  		*name = NULL;
>  
>  	mbox_flash->busy = true;
> -	rc = msg_send(mbox_flash, &msg, MBOX_DEFAULT_TIMEOUT);
> +	rc = msg_send(mbox_flash, &msg, mbox_flash->timeout);
>  	if (rc) {
>  		prlog(PR_ERR, "Failed to enqueue/send BMC MBOX message\n");
>  		return rc;
>  	}
>  
> -	if (wait_for_bmc(mbox_flash, MBOX_DEFAULT_TIMEOUT)) {
> +	if (wait_for_bmc(mbox_flash, mbox_flash->timeout)) {
>  		prlog(PR_ERR, "Error waiting for BMC\n");
>  		return rc;
>  	}
> @@ -905,6 +914,12 @@ static int protocol_init(struct mbox_flash_data *mbox_flash)
>  	mbox_flash->shift = 12;
>  
>  	/*
> +	 * For V1 we'll use this value.
> +	 * V2: The init code (may) update this
> +	 */
> +	mbox_flash->timeout = MBOX_DEFAULT_TIMEOUT;
> +
> +	/*
>  	 * Always attempt init with V2.
>  	 * The GET_MBOX_INFO response will confirm that the other side can
>  	 * talk V2, we'll update this variable then if V2 is not supported
> @@ -912,13 +927,13 @@ static int protocol_init(struct mbox_flash_data *mbox_flash)
>  	mbox_flash->version = 2;
>  
>  	msg_put_u8(&msg, 0, mbox_flash->version);
> -	rc = msg_send(mbox_flash, &msg, MBOX_DEFAULT_TIMEOUT);
> +	rc = msg_send(mbox_flash, &msg, mbox_flash->timeout);
>  	if (rc) {
>  		prlog(PR_ERR, "Failed to enqueue/send BMC MBOX message\n");
>  		return rc;
>  	}
>  
> -	rc = wait_for_bmc(mbox_flash, MBOX_DEFAULT_TIMEOUT);
> +	rc = wait_for_bmc(mbox_flash, mbox_flash->timeout);
>  	if (rc) {
>  		prlog(PR_ERR, "Error waiting for BMC\n");
>  		return rc;