[Skiboot] [PATCH RFC 10/12] opal-prd: Add firmware_request & firmware_notify implementations

[Vasant Hegde]

On 05/25/2017 12:35 PM, Jeremy Kerr wrote:
> This change adds the implementation of firmware_request() and
> firmware_notify(). To do this, we need to add a message queue, so that
> we can properly handle out-of-order messages coming from firmware.
>
> Signed-off-by: Jeremy Kerr <jk at ozlabs.org>
> ---
>  external/opal-prd/opal-prd.c | 151 ++++++++++++++++++++++++++++++++++++++++++-
>  external/opal-prd/thunk.S    |   2 +-
>  include/opal-api.h           |  16 +++++
>  3 files changed, 167 insertions(+), 2 deletions(-)
>

.../...

> +	n = 0;
> +	for (;;) {
> +		struct prd_msgq_item *item;
> +
> +		rc = read_prd_msg(ctx);
> +		if (rc)
> +			return -1;
> +
> +		msg = ctx->msg;
> +		if (msg->hdr.type == OPAL_PRD_MSG_TYPE_FIRMWARE_RESPONSE) {
> +			size = be64toh(msg->fw_resp.len);
> +			if (size > resp_len)
> +				return -1;
> +
> +			/* success! a valid response that fits into HBRT's
> +			 * resp buffer */
> +			memcpy(resp, msg->fw_resp.data, size);
> +			*resp_lenp = htobe64(size);
> +			return 0;
> +		}
> +
> +		/* not a response? queue up for later consumption */
> +		if (++n > max_msgq_len) {
> +			pr_log(LOG_ERR,
> +				"FW: too many messages queued (%d) while "
> +				"waiting for FIRMWARE_RESPONSE", n);
> +			return -1;
> +		}
> +		size = be16toh(msg->hdr.size);
> +		item = malloc(sizeof(*item) + size);

Validate malloc return value.

> +		memcpy(&item->msg, msg, size);
> +		list_add_tail(&ctx->msgq, &item->list);
> +	}
> +}
> +

.../...

> diff --git a/external/opal-prd/thunk.S b/external/opal-prd/thunk.S
> index b18e3cb..cca5890 100644
> --- a/external/opal-prd/thunk.S
> +++ b/external/opal-prd/thunk.S
> @@ -197,7 +197,7 @@ hinterface:
>  	DISABLED_THUNK(hservice_map_phys_mem)
>  	DISABLED_THUNK(hservice_unmap_phys_mem)
>  	DISABLED_THUNK(hservice_hcode_scom_update)
> -	DISABLED_THUNK(hservice_firmware_request)
> +	CALLBACK_THUNK(hservice_firmware_request)
>  .globl __hinterface_pad
>  __hinterface_pad:
>  	/* Reserved space for future growth */
> diff --git a/include/opal-api.h b/include/opal-api.h
> index 80033c6..e94747f 100644
> --- a/include/opal-api.h
> +++ b/include/opal-api.h
> @@ -1029,6 +1029,9 @@ enum opal_prd_msg_type {
>  	OPAL_PRD_MSG_TYPE_OCC_ERROR,	/* HBRT <-- OPAL */
>  	OPAL_PRD_MSG_TYPE_OCC_RESET,	/* HBRT <-- OPAL */
>  	OPAL_PRD_MSG_TYPE_OCC_RESET_NOTIFY, /* HBRT --> OPAL */
> +	OPAL_PRD_MSG_TYPE_FIRMWARE_REQUEST, /* HBRT --> OPAL */
> +	OPAL_PRD_MSG_TYPE_FIRMWARE_RESPONSE, /* HBRT <-- HBRT */

HBRT <-- OPAL

> +	OPAL_PRD_MSG_TYPE_FIRMWARE_NOTIFY, /* HBRT <-- HBRT */

ditto.

-Vasant