I'm sorry about the messed up subject saying [PATCH]. For some reason git
send-email is mangling the subject line. I'm new to trying to use this method
to send out patches. This is version 2 of my patch.
-Aaron
On Thursday, August 22, 2019 2:12:32 AM PDT Aaron Williams wrote:
> When large writes take place I saw a Samsung EVO 970+ return a status
> value of 0x13, PRP Offset Invalid. I tracked this down to the
> improper handling of PRP entries. The blocks the PRP entries are
> placed in cannot cross a page boundary and thus should be allocated
> on page boundaries. This is how the Linux kernel driver works.
>
> With this patch, the PRP pool is allocated on a page boundary and
> other than the very first allocation, the pool size is a multiple of
> the page size. Each page can hold (4096 / 8) - 1 entries since the
> last entry must point to the next page in the pool.
>
> Signed-off-by: Aaron Williams <awilli...@marvell.com>
> ---
> drivers/nvme/nvme.c | 28 ++++++++++++++++++----------
> 1 file changed, 18 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/nvme/nvme.c b/drivers/nvme/nvme.c
> index d4965e2ef6..bc4cf40b40 100644
> --- a/drivers/nvme/nvme.c
> +++ b/drivers/nvme/nvme.c
> @@ -73,6 +73,9 @@ static int nvme_setup_prps(struct nvme_dev *dev, u64
> *prp2, u64 *prp_pool;
> int length = total_len;
> int i, nprps;
> + u32 prps_per_page = (page_size >> 3) - 1;
> + u32 num_pages;
> +
> length -= (page_size - offset);
>
> if (length <= 0) {
> @@ -89,15 +92,19 @@ static int nvme_setup_prps(struct nvme_dev *dev, u64
> *prp2, }
>
> nprps = DIV_ROUND_UP(length, page_size);
> + num_pages = DIV_ROUND_UP(nprps, prps_per_page);
>
> if (nprps > dev->prp_entry_num) {
> free(dev->prp_pool);
> - dev->prp_pool = malloc(nprps << 3);
> + /* Always increase in increments of pages. It doesn't
waste
> + * much memory and reduces the number of allocations.
> + */
> + dev->prp_pool = memalign(page_size, num_pages *
page_size);
> if (!dev->prp_pool) {
> printf("Error: malloc prp_pool fail\n");
> return -ENOMEM;
> }
> - dev->prp_entry_num = nprps;
> + dev->prp_entry_num = prps_per_page * num_pages;
> }
>
> prp_pool = dev->prp_pool;
> @@ -788,14 +795,6 @@ static int nvme_probe(struct udevice *udev)
> }
> memset(ndev->queues, 0, NVME_Q_NUM * sizeof(struct nvme_queue
*));
>
> - ndev->prp_pool = malloc(MAX_PRP_POOL);
> - if (!ndev->prp_pool) {
> - ret = -ENOMEM;
> - printf("Error: %s: Out of memory!\n", udev->name);
> - goto free_nvme;
> - }
> - ndev->prp_entry_num = MAX_PRP_POOL >> 3;
> -
> ndev->cap = nvme_readq(&ndev->bar->cap);
> ndev->q_depth = min_t(int, NVME_CAP_MQES(ndev->cap) + 1,
NVME_Q_DEPTH);
> ndev->db_stride = 1 << NVME_CAP_STRIDE(ndev->cap);
> @@ -805,6 +804,15 @@ static int nvme_probe(struct udevice *udev)
> if (ret)
> goto free_queue;
>
> + /* Allocate after the page size is known */
> + ndev->prp_pool = memalign(ndev->page_size, MAX_PRP_POOL);
> + if (!ndev->prp_pool) {
> + ret = -ENOMEM;
> + printf("Error: %s: Out of memory!\n", udev->name);
> + goto free_nvme;
> + }
> + ndev->prp_entry_num = MAX_PRP_POOL >> 3;
> +
> ret = nvme_setup_io_queues(ndev);
> if (ret)
> goto free_queue;
_______________________________________________
U-Boot mailing list
U-Boot@lists.denx.de
https://lists.denx.de/listinfo/u-boot
