Re: [RFC PATCH 13/17] net: ipa: Add support for IPA v2.x in the driver's QMI interface

[Alex Elder <elder@ieee.org>]

On 9/19/21 10:08 PM, Sireesh Kodali wrote:
> On IPA v2.x, the modem doesn't send a DRIVER_INIT_COMPLETED, so we have
> to rely on the uc's IPA_UC_RESPONSE_INIT_COMPLETED to know when its
> ready. We add a function here that marks uc_ready = true. This function
> is called by ipa_uc.c when IPA_UC_RESPONSE_INIT_COMPLETED is handled.

This should use the new ipa_mem_find() interface for getting the
memory information for the ZIP region.

I don't know where the IPA_UC_RESPONSE_INIT_COMPLETED gets sent
but I presume it ends up calling ipa_qmi_signal_uc_loaded().

I think actually the DRIVER_INIT_COMPLETE message from the modem
is saying "I finished initializing the microcontroller."  And
I've wondered why there is a duplicate mechanism.  Maybe there
was a race or something.

					-Alex

> Signed-off-by: Sireesh Kodali <sireeshkodali1@gmail.com>
> Signed-off-by: Vladimir Lypak <vladimir.lypak@gmail.com>
> ---
>   drivers/net/ipa/ipa_qmi.c | 27 ++++++++++++++++++++++++++-
>   drivers/net/ipa/ipa_qmi.h | 10 ++++++++++
>   2 files changed, 36 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ipa/ipa_qmi.c b/drivers/net/ipa/ipa_qmi.c
> index 7e2fe701cc4d..876e2a004f70 100644
> --- a/drivers/net/ipa/ipa_qmi.c
> +++ b/drivers/net/ipa/ipa_qmi.c
> @@ -68,6 +68,11 @@
>    * - The INDICATION_REGISTER request and INIT_COMPLETE indication are
>    *   optional for non-initial modem boots, and have no bearing on the
>    *   determination of when things are "ready"
> + *
> + * Note that on IPA v2.x, the modem doesn't send a DRIVER_INIT_COMPLETE
> + * request. Thus, we rely on the uc's IPA_UC_RESPONSE_INIT_COMPLETED to know
> + * when the uc is ready. The rest of the process is the same on IPA v2.x and
> + * later IPA versions
>    */
>   
>   #define IPA_HOST_SERVICE_SVC_ID		0x31
> @@ -345,7 +350,12 @@ init_modem_driver_req(struct ipa_qmi *ipa_qmi)
>   			req.hdr_proc_ctx_tbl_info.start + mem->size - 1;
>   	}
>   
> -	/* Nothing to report for the compression table (zip_tbl_info) */
> +	mem = &ipa->mem[IPA_MEM_ZIP];
> +	if (mem->size) {
> +		req.zip_tbl_info_valid = 1;
> +		req.zip_tbl_info.start = ipa->mem_offset + mem->offset;
> +		req.zip_tbl_info.end = ipa->mem_offset + mem->size - 1;
> +	}
>   
>   	mem = ipa_mem_find(ipa, IPA_MEM_V4_ROUTE_HASHED);
>   	if (mem->size) {
> @@ -525,6 +535,21 @@ int ipa_qmi_setup(struct ipa *ipa)
>   	return ret;
>   }
>   
> +/* With IPA v2 modem is not required to send DRIVER_INIT_COMPLETE request to AP.
> + * We start operation as soon as IPA_UC_RESPONSE_INIT_COMPLETED irq is triggered.
> + */
> +void ipa_qmi_signal_uc_loaded(struct ipa *ipa)
> +{
> +	struct ipa_qmi *ipa_qmi = &ipa->qmi;
> +
> +	/* This is needed only on IPA 2.x */
> +	if (ipa->version > IPA_VERSION_2_6L)
> +		return;
> +
> +	ipa_qmi->uc_ready = true;
> +	ipa_qmi_ready(ipa_qmi);
> +}
> +
>   /* Tear down IPA QMI handles */
>   void ipa_qmi_teardown(struct ipa *ipa)
>   {
> diff --git a/drivers/net/ipa/ipa_qmi.h b/drivers/net/ipa/ipa_qmi.h
> index 856ef629ccc8..4962d88b0d22 100644
> --- a/drivers/net/ipa/ipa_qmi.h
> +++ b/drivers/net/ipa/ipa_qmi.h
> @@ -55,6 +55,16 @@ struct ipa_qmi {
>    */
>   int ipa_qmi_setup(struct ipa *ipa);
>   
> +/**
> + * ipa_qmi_signal_uc_loaded() - Signal that the UC has been loaded
> + * @ipa:		IPA pointer
> + *
> + * This is called when the uc indicates that it is ready. This exists, because
> + * on IPA v2.x, the modem does not send a DRIVER_INIT_COMPLETED. Thus we have
> + * to rely on the uc's INIT_COMPLETED response to know if it was initialized
> + */
> +void ipa_qmi_signal_uc_loaded(struct ipa *ipa);
> +
>   /**
>    * ipa_qmi_teardown() - Tear down IPA QMI handles
>    * @ipa:		IPA pointer
>