On Wed, 2019-08-21 at 16:34 +0100, Robin Murphy wrote: > On 21/08/2019 16:24, Will Deacon wrote: > > On Wed, Aug 21, 2019 at 09:53:12PM +0800, Yong Wu wrote: > >> MediaTek extend the arm v7s descriptor to support up to 34 bits PA where > >> the bit32 and bit33 are encoded in the bit9 and bit4 of the PTE > >> respectively. Meanwhile the iova still is 32bits. > >> > >> Regarding whether the pagetable address could be over 4GB, the mt8183 > >> support it while the previous mt8173 don't, thus keep it as is. > >> > >> Signed-off-by: Yong Wu <[email protected]> > >> --- > >> drivers/iommu/io-pgtable-arm-v7s.c | 32 +++++++++++++++++++++++++------- > >> include/linux/io-pgtable.h | 7 +++---- > >> 2 files changed, 28 insertions(+), 11 deletions(-) > > > > [...] > > > >> @@ -731,7 +747,9 @@ static struct io_pgtable *arm_v7s_alloc_pgtable(struct > >> io_pgtable_cfg *cfg, > >> { > >> struct arm_v7s_io_pgtable *data; > >> > >> - if (cfg->ias > ARM_V7S_ADDR_BITS || cfg->oas > ARM_V7S_ADDR_BITS) > >> + if (cfg->ias > ARM_V7S_ADDR_BITS || > >> + (cfg->oas > ARM_V7S_ADDR_BITS && > >> + !(cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_EXT))) > > > > Please can you instead change arm_v7s_alloc_pgtable() so that it allows an > > ias of up to 34 when the IO_PGTABLE_QUIRK_ARM_MTK_EXT is set? > > You mean oas, right? I believe the hardware *does* actually support a > 32-bit ias as well, but we shouldn't pretend to support that while > __arm_v7s_alloc_table() still only knows how to allocate normal-sized > tables.
Yes. The HW double the lvl1 pgtable, thus it supports 33bit iova actually. We may extend ias in the future. > > Robin. > > > > > With that change: > > > > Acked-by: Will Deacon <[email protected]> > > > > Will > > > > _______________________________________________ > Linux-mediatek mailing list > [email protected] > http://lists.infradead.org/mailman/listinfo/linux-mediatek _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
