diff options
| author | Andre Przywara <andre.przywara@arm.com> | 2021-03-02 15:43:43 +0000 |
|---|---|---|
| committer | Tom Rini <trini@konsulko.com> | 2021-03-19 10:36:55 -0400 |
| commit | 4c498796891a26a7283130f367a346096a6ccce7 (patch) | |
| tree | 46324d6775b7ef08eb43f92cbc43b937939fc001 | |
| parent | d0c04926cd054cf7360ec15913ac17a465f32603 (diff) | |
| download | u-boot-WIP/2021-03-19-assorted-fixes.tar.gz | |
nvme: Elaborate on cache maintenance operation in get/set_featuresWIP/2021-03-19-assorted-fixes
At the moment the nvme_get_features() and nvme_set_features() functions
carry a (somewhat misleading) comment about missing cache maintenance.
As it turns out, nvme_get_features() has no caller at all in the tree,
and nvme_set_features' only user doesn't use a DMA buffer.
Mention that in the comment, and leave some breadcrumbs for the future,
should those functions attract more users.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Michael Trimarchi <michael@amarulasolutions.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
| -rw-r--r-- | drivers/nvme/nvme.c | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/drivers/nvme/nvme.c b/drivers/nvme/nvme.c index c9efeff4bc..c61dab20c5 100644 --- a/drivers/nvme/nvme.c +++ b/drivers/nvme/nvme.c @@ -489,6 +489,7 @@ int nvme_get_features(struct nvme_dev *dev, unsigned fid, unsigned nsid, dma_addr_t dma_addr, u32 *result) { struct nvme_command c; + int ret; memset(&c, 0, sizeof(c)); c.features.opcode = nvme_admin_get_features; @@ -496,12 +497,20 @@ int nvme_get_features(struct nvme_dev *dev, unsigned fid, unsigned nsid, c.features.prp1 = cpu_to_le64(dma_addr); c.features.fid = cpu_to_le32(fid); + ret = nvme_submit_admin_cmd(dev, &c, result); + /* - * TODO: add cache invalidate operation when the size of - * the DMA buffer is known + * TODO: Add some cache invalidation when a DMA buffer is involved + * in the request, here and before the command gets submitted. The + * buffer size varies by feature, also some features use a different + * field in the command packet to hold the buffer address. + * Section 5.21.1 (Set Features command) in the NVMe specification + * details the buffer requirements for each feature. + * + * At the moment there is no user of this function. */ - return nvme_submit_admin_cmd(dev, &c, result); + return ret; } int nvme_set_features(struct nvme_dev *dev, unsigned fid, unsigned dword11, @@ -516,8 +525,14 @@ int nvme_set_features(struct nvme_dev *dev, unsigned fid, unsigned dword11, c.features.dword11 = cpu_to_le32(dword11); /* - * TODO: add cache flush operation when the size of - * the DMA buffer is known + * TODO: Add a cache clean (aka flush) operation when a DMA buffer is + * involved in the request. The buffer size varies by feature, also + * some features use a different field in the command packet to hold + * the buffer address. Section 5.21.1 (Set Features command) in the + * NVMe specification details the buffer requirements for each + * feature. + * At the moment the only user of this function is not using + * any DMA buffer at all. */ return nvme_submit_admin_cmd(dev, &c, result); |