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| author | Dave Jiang <dave.jiang@intel.com> | 2021-01-22 11:46:00 -0700 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2021-01-26 22:58:55 +0530 |
| commit | 03d939c7e3d8800a9feb54808929c5776ac510eb (patch) | |
| tree | 007b7998d6618bd6423be049e5e5661fc8907173 | |
| parent | 9f3c14d4433b98c87f958128045539f297a2fa6d (diff) | |
| download | linux-03d939c7e3d8800a9feb54808929c5776ac510eb.tar.bz2 | |
dmaengine: idxd: add module parameter to force disable of SVA
Add a module parameter that overrides the SVA feature enabling. This keeps
the driver in legacy mode even when intel_iommu=sm_on is set. In this mode,
the descriptor fields must be programmed with dma_addr_t from the Linux DMA
API for source, destination, and completion descriptors.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/161134110457.4005461.13171197785259115852.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 6 | ||||
| -rw-r--r-- | drivers/dma/idxd/init.c | 8 |
2 files changed, 13 insertions, 1 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index c722ec19cd00..c25786b95419 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1673,6 +1673,12 @@ In such case C2/C3 won't be used again. idle=nomwait: Disable mwait for CPU C-states + idxd.sva= [HW] + Format: <bool> + Allow force disabling of Shared Virtual Memory (SVA) + support for the idxd driver. By default it is set to + true (1). + ieee754= [MIPS] Select IEEE Std 754 conformance mode Format: { strict | legacy | 2008 | relaxed } Default: strict diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c index 25cc947c6179..9687a24ff982 100644 --- a/drivers/dma/idxd/init.c +++ b/drivers/dma/idxd/init.c @@ -26,6 +26,10 @@ MODULE_VERSION(IDXD_DRIVER_VERSION); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Intel Corporation"); +static bool sva = true; +module_param(sva, bool, 0644); +MODULE_PARM_DESC(sva, "Toggle SVA support on/off"); + #define DRV_NAME "idxd" bool support_enqcmd; @@ -338,12 +342,14 @@ static int idxd_probe(struct idxd_device *idxd) idxd_device_init_reset(idxd); dev_dbg(dev, "IDXD reset complete\n"); - if (IS_ENABLED(CONFIG_INTEL_IDXD_SVM)) { + if (IS_ENABLED(CONFIG_INTEL_IDXD_SVM) && sva) { rc = idxd_enable_system_pasid(idxd); if (rc < 0) dev_warn(dev, "Failed to enable PASID. No SVA support: %d\n", rc); else set_bit(IDXD_FLAG_PASID_ENABLED, &idxd->flags); + } else if (!sva) { + dev_warn(dev, "User forced SVA off via module param.\n"); } idxd_read_caps(idxd); |