Re: [PATCH v2 09/34] media: iris: initialize shared queues for host and firmware communication

[Dikshita Agarwal <quic_dikshita@quicinc.com>]

On 12/19/2023 12:16 AM, Dmitry Baryshkov wrote:
> On 18/12/2023 13:32, Dikshita Agarwal wrote:
>> Shared queues are used for communication between driver and firmware.
>> There are 3 types of queues:
>> Command queue - driver to write any command to firmware.
>> Message queue - firmware to send any response to driver.
>> Debug queue - firmware to write debug message.
>>
>> Above queues are initialized and configured to firmware during probe.
>>
>> Signed-off-by: Dikshita Agarwal <quic_dikshita@quicinc.com>
>> ---
>>   drivers/media/platform/qcom/vcodec/iris/Makefile   |  2 ++
>>   .../media/platform/qcom/vcodec/iris/iris_core.h    | 11 ++++++++
>>   .../media/platform/qcom/vcodec/iris/iris_probe.c   | 31
>> ++++++++++++++++++++++
>>   3 files changed, 44 insertions(+)
>>
>> diff --git a/drivers/media/platform/qcom/vcodec/iris/Makefile
>> b/drivers/media/platform/qcom/vcodec/iris/Makefile
>> index 12a74de..59798e5d 100644
>> --- a/drivers/media/platform/qcom/vcodec/iris/Makefile
>> +++ b/drivers/media/platform/qcom/vcodec/iris/Makefile
>> @@ -1,3 +1,5 @@
>> +iris-objs += ../hfi_queue.o
>> +
>>   iris-objs += iris_probe.o \
>>                resources.o \
>>                iris_state.o
>> diff --git a/drivers/media/platform/qcom/vcodec/iris/iris_core.h
>> b/drivers/media/platform/qcom/vcodec/iris/iris_core.h
>> index 56a5b7d..77124f9 100644
>> --- a/drivers/media/platform/qcom/vcodec/iris/iris_core.h
>> +++ b/drivers/media/platform/qcom/vcodec/iris/iris_core.h
>> @@ -9,6 +9,7 @@
>>   #include <linux/types.h>
>>   #include <media/v4l2-device.h>
>>   +#include "../hfi_queue.h"
>>   #include "iris_state.h"
>>     /**
>> @@ -30,6 +31,11 @@
>>    * @reset_tbl: table of iris reset clocks
>>    * @reset_count: count of iris reset clocks
>>    * @state: current state of core
>> + * @iface_q_table: Interface queue table memory
>> + * @command_queue: shared interface queue to send commands to firmware
>> + * @message_queue: shared interface queue to receive responses from
>> firmware
>> + * @debug_queue: shared interface queue to receive debug info from firmware
>> + * @sfr: SFR register memory
>>    */
>>     struct iris_core {
>> @@ -49,6 +55,11 @@ struct iris_core {
>>       struct reset_info            *reset_tbl;
>>       u32                    reset_count;
>>       enum iris_core_state            state;
>> +    struct mem_desc                iface_q_table;
>> +    struct iface_q_info            command_queue;
>> +    struct iface_q_info            message_queue;
>> +    struct iface_q_info            debug_queue;
>> +    struct mem_desc                sfr;
>>   };
>>     #endif
>> diff --git a/drivers/media/platform/qcom/vcodec/iris/iris_probe.c
>> b/drivers/media/platform/qcom/vcodec/iris/iris_probe.c
>> index 7bb9c92..fd349a3 100644
>> --- a/drivers/media/platform/qcom/vcodec/iris/iris_probe.c
>> +++ b/drivers/media/platform/qcom/vcodec/iris/iris_probe.c
>> @@ -7,6 +7,7 @@
>>   #include <linux/of_device.h>
>>   #include <linux/platform_device.h>
>>   +#include "../hfi_queue.h"
>>   #include "iris_core.h"
>>   #include "resources.h"
>>   @@ -50,6 +51,10 @@ static void iris_remove(struct platform_device *pdev)
>>       if (!core)
>>           return;
>>   +    hfi_queue_deinit(core->dev, &core->iface_q_table, &core->sfr,
>> +             &core->command_queue, &core->message_queue,
>> +             &core->debug_queue);
>> +
>>       video_unregister_device(core->vdev_dec);
>>         v4l2_device_unregister(&core->v4l2_dev);
>> @@ -59,6 +64,7 @@ static int iris_probe(struct platform_device *pdev)
>>   {
>>       struct device *dev = &pdev->dev;
>>       struct iris_core *core;
>> +    u64 dma_mask;
>>       int ret;
>>         core = devm_kzalloc(&pdev->dev, sizeof(*core), GFP_KERNEL);
>> @@ -91,8 +97,33 @@ static int iris_probe(struct platform_device *pdev)
>>         platform_set_drvdata(pdev, core);
>>   +    /*
>> +     * Specify the max value of address space, which can be used
>> +     * for buffer transactions.
>> +     */
>> +    dma_mask = DMA_BIT_MASK(32);
>> +    dma_mask &= ~BIT(29);
>> +
>> +    ret = dma_set_mask_and_coherent(dev, dma_mask);
>> +    if (ret)
>> +        goto err_vdev_unreg;
>> +
>> +    dma_set_max_seg_size(&pdev->dev, (unsigned int)DMA_BIT_MASK(32));
>> +    dma_set_seg_boundary(&pdev->dev, (unsigned long)DMA_BIT_MASK(64));
> 
> This isn't related to queues.
> 
Using this DMA mask, we define the upper limit of memory to be used to
allocate the queues, hence this is added with this patch.
>> +
>> +    ret = hfi_queue_init(core->dev, &core->iface_q_table, &core->sfr,
>> +                 &core->command_queue, &core->message_queue,
>> +                 &core->debug_queue, core);
>> +    if (ret) {
>> +        dev_err_probe(core->dev, ret,
>> +                  "%s: interface queues init failed\n", __func__);
>> +        goto err_vdev_unreg;
>> +    }
>> +
>>       return ret;
>>   +err_vdev_unreg:
>> +    iris_unregister_video_device(core);
>>   err_v4l2_unreg:
>>       v4l2_device_unregister(&core->v4l2_dev);
>>   
>