Re: [PATCH v4 13/17] remoteproc: create vdev subdevice with specific dma memory pool

[Suman Anna <s-anna@ti.com>]

On 10/23/18 8:22 PM, Suman Anna wrote:
> On 9/27/18 3:18 PM, Wendy Liang wrote:
>> Hi Loic,
>>
>>
>> On Thu, Sep 27, 2018 at 12:22 PM Loic PALLARDY <loic.pallardy@st.com> wrote:
>>>
>>> Hi Wendy
>>>
>>>> -----Original Message-----
>>>> From: Wendy Liang <sunnyliangjy@gmail.com>
>>>> Sent: Thursday, September 27, 2018 7:17 PM
>>>> To: Loic PALLARDY <loic.pallardy@st.com>
>>>> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>; Ohad Ben-Cohen
>>>> <ohad@wizery.com>; linux-remoteproc@vger.kernel.org; Linux Kernel
>>>> Mailing List <linux-kernel@vger.kernel.org>; Arnaud POULIQUEN
>>>> <arnaud.pouliquen@st.com>; benjamin.gaignard@linaro.org; Suman Anna
>>>> <s-anna@ti.com>
>>>> Subject: Re: [PATCH v4 13/17] remoteproc: create vdev subdevice with
>>>> specific dma memory pool
>>>>
>>>> On Fri, Jul 27, 2018 at 6:16 AM Loic Pallardy <loic.pallardy@st.com> wrote:
>>>>>
>>>>> This patch creates a dedicated vdev subdevice for each vdev declared
>>>>> in firmware resource table and associates carveout named "vdev%dbuffer"
>>>>> (with %d vdev index in resource table) if any as dma coherent memory
>>>> pool.
>>>>>
>>>>> Then vdev subdevice is used as parent for virtio device.
>>>>>
>>>>> Signed-off-by: Loic Pallardy <loic.pallardy@st.com>
>>>>> ---
>>>>>  drivers/remoteproc/remoteproc_core.c     | 35
>>>> +++++++++++++++++++++++---
>>>>>  drivers/remoteproc/remoteproc_internal.h |  1 +
>>>>>  drivers/remoteproc/remoteproc_virtio.c   | 42
>>>> +++++++++++++++++++++++++++++++-
>>>>>  include/linux/remoteproc.h               |  1 +
>>>>>  4 files changed, 75 insertions(+), 4 deletions(-)
>>>>>
>>>>> diff --git a/drivers/remoteproc/remoteproc_core.c
>>>> b/drivers/remoteproc/remoteproc_core.c
>>>>> index 4edc6f0..adcc66e 100644
>>>>> --- a/drivers/remoteproc/remoteproc_core.c
>>>>> +++ b/drivers/remoteproc/remoteproc_core.c
>>>>> @@ -39,6 +39,7 @@
>>>>>  #include <linux/idr.h>
>>>>>  #include <linux/elf.h>
>>>>>  #include <linux/crc32.h>
>>>>> +#include <linux/of_reserved_mem.h>
>>>>>  #include <linux/virtio_ids.h>
>>>>>  #include <linux/virtio_ring.h>
>>>>>  #include <asm/byteorder.h>
>>>>> @@ -145,7 +146,7 @@ static void rproc_disable_iommu(struct rproc
>>>> *rproc)
>>>>>         iommu_domain_free(domain);
>>>>>  }
>>>>>
>>>>> -static phys_addr_t rproc_va_to_pa(void *cpu_addr)
>>>>> +phys_addr_t rproc_va_to_pa(void *cpu_addr)
>>>>>  {
>>>>>         /*
>>>>>          * Return physical address according to virtual address location
>>>>> @@ -160,6 +161,7 @@ static phys_addr_t rproc_va_to_pa(void
>>>> *cpu_addr)
>>>>>         WARN_ON(!virt_addr_valid(cpu_addr));
>>>>>         return virt_to_phys(cpu_addr);
>>>>>  }
>>>>> +EXPORT_SYMBOL(rproc_va_to_pa);
>>>>>
>>>>>  /**
>>>>>   * rproc_da_to_va() - lookup the kernel virtual address for a remoteproc
>>>> address
>>>>> @@ -423,6 +425,20 @@ static void rproc_vdev_do_stop(struct
>>>> rproc_subdev *subdev, bool crashed)
>>>>>  }
>>>>>
>>>>>  /**
>>>>> + * rproc_rvdev_release() - release the existence of a rvdev
>>>>> + *
>>>>> + * @dev: the subdevice's dev
>>>>> + */
>>>>> +static void rproc_rvdev_release(struct device *dev)
>>>>> +{
>>>>> +       struct rproc_vdev *rvdev = container_of(dev, struct rproc_vdev, dev);
>>>>> +
>>>>> +       of_reserved_mem_device_release(dev);
>>>>> +
>>>>> +       kfree(rvdev);
>>>>> +}
>>>>> +
>>>>> +/**
>>>>>   * rproc_handle_vdev() - handle a vdev fw resource
>>>>>   * @rproc: the remote processor
>>>>>   * @rsc: the vring resource descriptor
>>>>> @@ -455,6 +471,7 @@ static int rproc_handle_vdev(struct rproc *rproc,
>>>> struct fw_rsc_vdev *rsc,
>>>>>         struct device *dev = &rproc->dev;
>>>>>         struct rproc_vdev *rvdev;
>>>>>         int i, ret;
>>>>> +       char name[16];
>>>>>
>>>>>         /* make sure resource isn't truncated */
>>>>>         if (sizeof(*rsc) + rsc->num_of_vrings * sizeof(struct
>>>> fw_rsc_vdev_vring)
>>>>> @@ -488,6 +505,18 @@ static int rproc_handle_vdev(struct rproc *rproc,
>>>> struct fw_rsc_vdev *rsc,
>>>>>         rvdev->rproc = rproc;
>>>>>         rvdev->index = rproc->nb_vdev++;
>>>>>
>>>>> +       /* Initialise vdev subdevice */
>>>>> +       snprintf(name, sizeof(name), "vdev%dbuffer", rvdev->index);
>>>>> +       rvdev->dev.parent = rproc->dev.parent;
>>>>> +       rvdev->dev.release = rproc_rvdev_release;
>>>>> +       dev_set_name(&rvdev->dev, "%s#%s", dev_name(rvdev-
>>>>> dev.parent), name);
>>>>> +       dev_set_drvdata(&rvdev->dev, rvdev);
>>>>> +       dma_set_coherent_mask(&rvdev->dev, DMA_BIT_MASK(32));
>>>> I tried the latest kernel, this function will not set the DMA coherent mask as
>>>> dma_supported() of the &rvdev->dev will return false.
>>>> As this is a device created at run time, should it be force to support DMA?
>>>> should it directly set the dma_coherent_mask?
>>>
>>> Thanks for pointing me this issue. I tested on top of 4.18-rc1 few months ago...
>>> Could you please give me kernel version on which you are testing the series?
>>> Is you platform 32bit or 64bit ?
>>> I'll rebase and check on my side.
>>
>> I am testing with 4.19-rc4 on aarch64 platform.
> 
> Btw, I ran into this on my v7 platform as well (4.19-rc6). The
> dma_set_coherent_mask fails with error EIO. I did get my allocations
> through though.

Correction, that was before Patch 17. With patch 17, this fails.

regards
Suman

> 
> regards
> Suman
> 
>>
>> Best Regards,
>> Wendy
>>>
>>> Regards,
>>> Loic
>>>
>>>>
>>>>> +
>>>>> +       ret = device_register(&rvdev->dev);
>>>>> +       if (ret)
>>>>> +               goto free_rvdev;
>>>>> +
>>>>>         /* parse the vrings */
>>>>>         for (i = 0; i < rsc->num_of_vrings; i++) {
>>>>>                 ret = rproc_parse_vring(rvdev, rsc, i);
>>>>> @@ -518,7 +547,7 @@ static int rproc_handle_vdev(struct rproc *rproc,
>>>> struct fw_rsc_vdev *rsc,
>>>>>         for (i--; i >= 0; i--)
>>>>>                 rproc_free_vring(&rvdev->vring[i]);
>>>>>  free_rvdev:
>>>>> -       kfree(rvdev);
>>>>> +       device_unregister(&rvdev->dev);
>>>>>         return ret;
>>>>>  }
>>>>>
>>>>> @@ -536,7 +565,7 @@ void rproc_vdev_release(struct kref *ref)
>>>>>
>>>>>         rproc_remove_subdev(rproc, &rvdev->subdev);
>>>>>         list_del(&rvdev->node);
>>>>> -       kfree(rvdev);
>>>>> +       device_unregister(&rvdev->dev);
>>>>>  }
>>>>>
>>>>>  /**
>>>>> diff --git a/drivers/remoteproc/remoteproc_internal.h
>>>> b/drivers/remoteproc/remoteproc_internal.h
>>>>> index f6cad24..bfeacfd 100644
>>>>> --- a/drivers/remoteproc/remoteproc_internal.h
>>>>> +++ b/drivers/remoteproc/remoteproc_internal.h
>>>>> @@ -52,6 +52,7 @@ struct dentry *rproc_create_trace_file(const char
>>>> *name, struct rproc *rproc,
>>>>>  int rproc_alloc_vring(struct rproc_vdev *rvdev, int i);
>>>>>
>>>>>  void *rproc_da_to_va(struct rproc *rproc, u64 da, int len);
>>>>> +phys_addr_t rproc_va_to_pa(void *cpu_addr);
>>>>>  int rproc_trigger_recovery(struct rproc *rproc);
>>>>>
>>>>>  int rproc_elf_sanity_check(struct rproc *rproc, const struct firmware *fw);
>>>>> diff --git a/drivers/remoteproc/remoteproc_virtio.c
>>>> b/drivers/remoteproc/remoteproc_virtio.c
>>>>> index de21f62..9ee63c0 100644
>>>>> --- a/drivers/remoteproc/remoteproc_virtio.c
>>>>> +++ b/drivers/remoteproc/remoteproc_virtio.c
>>>>> @@ -17,7 +17,9 @@
>>>>>   * GNU General Public License for more details.
>>>>>   */
>>>>>
>>>>> +#include <linux/dma-mapping.h>
>>>>>  #include <linux/export.h>
>>>>> +#include <linux/of_reserved_mem.h>
>>>>>  #include <linux/remoteproc.h>
>>>>>  #include <linux/virtio.h>
>>>>>  #include <linux/virtio_config.h>
>>>>> @@ -315,10 +317,48 @@ static void rproc_virtio_dev_release(struct device
>>>> *dev)
>>>>>  int rproc_add_virtio_dev(struct rproc_vdev *rvdev, int id)
>>>>>  {
>>>>>         struct rproc *rproc = rvdev->rproc;
>>>>> -       struct device *dev = &rproc->dev;
>>>>> +       struct device *dev = &rvdev->dev;
>>>>>         struct virtio_device *vdev = &rvdev->vdev;
>>>>> +       struct rproc_mem_entry *mem;
>>>>>         int ret;
>>>>>
>>>>> +       /* Try to find dedicated vdev buffer carveout */
>>>>> +       mem = rproc_find_carveout_by_name(rproc, "vdev%dbuffer", rvdev-
>>>>> index);
>>>>> +       if (mem) {
>>>>> +               phys_addr_t pa;
>>>>> +
>>>>> +               if (mem->of_resm_idx != -1) {
>>>>> +                       struct device_node *np = rproc->dev.parent->of_node;
>>>>> +
>>>>> +                       /* Associate reserved memory to vdev device */
>>>>> +                       ret = of_reserved_mem_device_init_by_idx(dev, np,
>>>>> +                                                                mem->of_resm_idx);
>>>>> +                       if (ret) {
>>>>> +                               dev_err(dev, "Can't associate reserved memory\n");
>>>>> +                               goto out;
>>>>> +                       }
>>>>> +               } else {
>>>>> +                       if (mem->va) {
>>>>> +                               dev_warn(dev, "vdev %d buffer already mapped\n",
>>>>> +                                        rvdev->index);
>>>>> +                               pa = rproc_va_to_pa(mem->va);
>>>>> +                       } else {
>>>>> +                               /* Use dma address as carveout no memmapped yet */
>>>>> +                               pa = (phys_addr_t)mem->dma;
>>>>> +                       }
>>>>> +
>>>>> +                       /* Associate vdev buffer memory pool to vdev subdev */
>>>>> +                       ret = dmam_declare_coherent_memory(dev, pa,
>>>>> +                                                          mem->da,
>>>>> +                                                          mem->len,
>>>>> +                                                          DMA_MEMORY_EXCLUSIVE);
>>>>> +                       if (ret < 0) {
>>>>> +                               dev_err(dev, "Failed to associate buffer\n");
>>>>> +                               goto out;
>>>>> +                       }
>>>>> +               }
>>>>> +       }
>>>>> +
>>>>>         vdev->id.device = id,
>>>>>         vdev->config = &rproc_virtio_config_ops,
>>>>>         vdev->dev.parent = dev;
>>>>> diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
>>>>> index 6b3a234..2921dd2 100644
>>>>> --- a/include/linux/remoteproc.h
>>>>> +++ b/include/linux/remoteproc.h
>>>>> @@ -547,6 +547,7 @@ struct rproc_vdev {
>>>>>         struct kref refcount;
>>>>>
>>>>>         struct rproc_subdev subdev;
>>>>> +       struct device dev;
>>>>>
>>>>>         unsigned int id;
>>>>>         struct list_head node;
>>>>> --
>>>>> 1.9.1
>>>>>
>>>>> --
>>>>> To unsubscribe from this list: send the line "unsubscribe linux-remoteproc"
>>>> in
>>>>> the body of a message to majordomo@vger.kernel.org
>>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>