| Message ID | 1373021097-32420-4-git-send-email-hdoyu@nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
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/? s/tegra-swgroup.h/tegra-smmu.h/? > +#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. > +#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?
Stephen Warren <swarren@wwwdotorg.org> 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.
On 07/29/2013 04:53 AM, Hiroshi Doyu wrote: > Stephen Warren <swarren@wwwdotorg.org> 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". Why does the PMC care? An explanation of exactly what SW needs to know about these groups and why would be a good idea. >> s/tegra-swgroup.h/tegra-smmu.h/? > > Is "tegra-memory-clients.h" preferable, then? Perhaps, although aren't these IDs specific to the connection between modules and the SMMU? Or, are these IDs some more global concept; the HW modules in question pass the same IDs to both the SMMU and to other HW modules for some reason? >>> +#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. If the values are only needed to write the DT content, I'd tend to prefer not defining them in a header in <dt-bindings/>; I consider that directory a definition of the constants that define the ABI itself, not as a random place to put useful things for DT. You can include headers in the *.dts directory itself.
On Mon, 29 Jul 2013 19:45:15 +0200 Stephen Warren <swarren@wwwdotorg.org> wrote: > On 07/29/2013 04:53 AM, Hiroshi Doyu wrote: > > Stephen Warren <swarren@wwwdotorg.org> 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". > > Why does the PMC care? An explanation of exactly what SW needs to know > about these groups and why would be a good idea. Joseph, can you explain a bit here?
diff --git a/include/dt-bindings/memory/tegra-swgroup.h b/include/dt-bindings/memory/tegra-swgroup.h new file mode 100644 index 0000000..4cfa769 --- /dev/null +++ b/include/dt-bindings/memory/tegra-swgroup.h @@ -0,0 +1,50 @@ +/* + * This header provides constants for binding nvidia,swgroup ID + */ + +#ifndef _DT_BINDINGS_MEMORY_TEGRA_SWGROUP_H +#define _DT_BINDINGS_MEMORY_TEGRA_SWGROUP_H + +#define TEGRA_SWGROUP_AFI 0 +#define TEGRA_SWGROUP_AVPC 1 +#define TEGRA_SWGROUP_DC 2 +#define TEGRA_SWGROUP_DCB 3 +#define TEGRA_SWGROUP_EPP 4 +#define TEGRA_SWGROUP_G2 5 +#define TEGRA_SWGROUP_HC 6 +#define TEGRA_SWGROUP_HDA 7 +#define TEGRA_SWGROUP_ISP 8 +#define TEGRA_SWGROUP_ISP2 SWGID_ISP +/* UNUSED: 9 */ +/* UNUSED: 10 */ +#define TEGRA_SWGROUP_MPE 11 +#define TEGRA_SWGROUP_MSENC SWGID_MPE +#define TEGRA_SWGROUP_NV 12 +#define TEGRA_SWGROUP_NV2 13 +#define TEGRA_SWGROUP_PPCS 14 +#define TEGRA_SWGROUP_SATA2 15 +#define TEGRA_SWGROUP_SATA 16 +#define TEGRA_SWGROUP_VDE 17 +#define TEGRA_SWGROUP_VI 18 +#define TEGRA_SWGROUP_VIC 19 +#define TEGRA_SWGROUP_XUSB_HOST 20 +#define TEGRA_SWGROUP_XUSB_DEV 21 +#define TEGRA_SWGROUP_A9AVP 22 +#define TEGRA_SWGROUP_TSEC 23 +#define TEGRA_SWGROUP_PPCS1 24 +/* UNUSED: 25 */ +/* UNUSED: 26 */ +/* UNUSED: 27 */ +/* UNUSED: 28 */ +/* UNUSED: 29 */ +/* UNUSED: 30 */ +/* UNUSED: 31 */ + +/* Reserved: 32-63 */ + +#define TEGRA_SWGROUP_BIT(x) (1ULL << TEGRA_SWGROUP_##x) + +#define TEGRA30_SWGROUP_ALL <0x00000000 0x000779ff> +#define TEGRA114_SWGROUP_ALL <0x00000000 0x01b659fe> + +#endif /* _DT_BINDINGS_MEMORY_TEGRA_SWGROUP_H */
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. Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com> --- include/dt-bindings/memory/tegra-swgroup.h | 50 ++++++++++++++++++++++++++++ 1 file changed, 50 insertions(+) create mode 100644 include/dt-bindings/memory/tegra-swgroup.h