diff options
| author | Alexey Kardashevskiy <aik@ozlabs.ru> | 2021-10-06 15:47:35 +1100 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-10-09 00:15:57 +1100 |
| commit | 3872731187141d5d0a5c4fb30007b8b9ec36a44d (patch) | |
| tree | 27137225324d6bfd83a49cb09a24b028e9fcc246 /arch/powerpc/platforms | |
| parent | e4e737bb5c170df6135a127739a9e6148ee3da82 (diff) | |
powerps/pseries/dma: Add support for 2M IOMMU page size
The upcoming PAPR spec adds a 2M page size, bit 23 right after 16G page
size in the "ibm,query-pe-dma-window" call.
This adds support for the new page size. Since the new page size is out
of sorted order, this changes the loop to not assume that shift[] is
sorted.
This has now been tested and is known to work on a pre-release version
of phyp.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Leonardo Bras <leobras.c@gmail.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211006044735.1114669-1-aik@ozlabs.ru
Diffstat (limited to 'arch/powerpc/platforms')
| -rw-r--r-- | arch/powerpc/platforms/pseries/iommu.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index dab5c56ffd0e..269f61d519c2 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -1159,14 +1159,15 @@ static void reset_dma_window(struct pci_dev *dev, struct device_node *par_dn) /* Return largest page shift based on "IO Page Sizes" output of ibm,query-pe-dma-window. */ static int iommu_get_page_shift(u32 query_page_size) { - /* Supported IO page-sizes according to LoPAR */ + /* Supported IO page-sizes according to LoPAR, note that 2M is out of order */ const int shift[] = { __builtin_ctzll(SZ_4K), __builtin_ctzll(SZ_64K), __builtin_ctzll(SZ_16M), __builtin_ctzll(SZ_32M), __builtin_ctzll(SZ_64M), __builtin_ctzll(SZ_128M), - __builtin_ctzll(SZ_256M), __builtin_ctzll(SZ_16G) + __builtin_ctzll(SZ_256M), __builtin_ctzll(SZ_16G), __builtin_ctzll(SZ_2M) }; int i = ARRAY_SIZE(shift) - 1; + int ret = 0; /* * On LoPAR, ibm,query-pe-dma-window outputs "IO Page Sizes" using a bit field: @@ -1176,11 +1177,10 @@ static int iommu_get_page_shift(u32 query_page_size) */ for (; i >= 0 ; i--) { if (query_page_size & (1 << i)) - return shift[i]; + ret = max(ret, shift[i]); } - /* No valid page size found. */ - return 0; + return ret; } static struct property *ddw_property_create(const char *propname, u32 liobn, u64 dma_addr, |