Stephen Warren <swarren@xxxxxxxxxxxxx> wrote @ Wed, 17 Jul 2013 01:07:12 +0200: > On 07/05/2013 04:44 AM, Hiroshi Doyu wrote: > > Create a header file to define the swgroup IDs used by the IOMMU(SMMU) > > binding. "swgroup" is a group of H/W clients in Tegra SoC from S/W POV. > > > > This will allow the same header to be used by both device tree files, > > and drivers implementing this binding, which guarantees that the two > > stay in sync. This also makes device trees more readable by using names > > instead of magic numbers. > > Why does the driver need these constants; shouldn't it simply support > 0..n SW group IDs that all work the same way? Or, is there some reason > for it to know the identities? > > > diff --git a/include/dt-bindings/memory/tegra-swgroup.h b/include/dt-bindings/memory/tegra-swgroup.h > > s/memory/iommu/? This info would be used in PMC code as well, which H/W belongs to which swgroup. So I use the term "memory(-client)" instead of "iommu". > s/tegra-swgroup.h/tegra-smmu.h/? Is "tegra-memory-clients.h" preferable, then? > > +#define TEGRA_SWGROUP_AFI 0 > > Should this file document which values are valid for which SoCs? Should > there be separate files for each SoC; I don't know if it's guaranteed > that IDs won't be re-assigned between different SoCs. I've checked all SoC which I can refer. Those IDs are calculated from the register offset. But I haven't got any explicit guarantee from H/W designers yet. > > +#define TEGRA_SWGROUP_BIT(x) (1ULL << TEGRA_SWGROUP_##x) > > + > > +#define TEGRA30_SWGROUP_ALL <0x00000000 0x000779ff> > > +#define TEGRA114_SWGROUP_ALL <0x00000000 0x01b659fe> > > Are those 3 values needed by DT files, or just the driver? Only from DT. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
