Hi Bin, On Fri, Dec 11, 2020 at 2:57 PM Bin Meng <bmeng...@gmail.com> wrote:
> HI Padmarao, > > On Fri, Dec 11, 2020 at 4:23 PM Padmarao Begari <padmara...@gmail.com> > wrote: > > > > Hi Bin, > > > > On Fri, Dec 11, 2020 at 1:22 PM Bin Meng <bmeng...@gmail.com> wrote: > >> > >> Hi Padmarao, > >> > >> On Fri, Dec 11, 2020 at 3:10 PM Padmarao Begari <padmara...@gmail.com> > wrote: > >> > > >> > Hi Bin, > >> > > >> > On Thu, Dec 10, 2020 at 4:11 PM Bin Meng <bmeng...@gmail.com> wrote: > >> >> > >> >> Hi Padmarao, > >> >> > >> >> On Thu, Dec 3, 2020 at 4:43 AM Padmarao Begari > >> >> <padmarao.beg...@microchip.com> wrote: > >> >> > > >> >> > dma_addr_t holds any valid DMA address. If the DMA API only uses > 32/64-bit > >> >> > addresses, dma_addr_t need only be 32/64 bits wide. > >> >> > > >> >> > Signed-off-by: Padmarao Begari <padmarao.beg...@microchip.com> > >> >> > Reviewed-by: Anup Patel <anup.pa...@wdc.com> > >> >> > --- > >> >> > arch/riscv/Kconfig | 4 ++++ > >> >> > arch/riscv/include/asm/types.h | 4 ++++ > >> >> > 2 files changed, 8 insertions(+) > >> >> > > >> >> > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > >> >> > index 30b05408b1..55eaee2da6 100644 > >> >> > --- a/arch/riscv/Kconfig > >> >> > +++ b/arch/riscv/Kconfig > >> >> > @@ -152,6 +152,10 @@ config 32BIT > >> >> > config 64BIT > >> >> > bool > >> >> > > >> >> > +config DMA_ADDR_T_64BIT > >> >> > + bool > >> >> > + default y if 64BIT > >> >> > + > >> >> > config SIFIVE_CLINT > >> >> > bool > >> >> > depends on RISCV_MMODE || SPL_RISCV_MMODE > >> >> > diff --git a/arch/riscv/include/asm/types.h > b/arch/riscv/include/asm/types.h > >> >> > index 403cf9a48f..b800b2d221 100644 > >> >> > --- a/arch/riscv/include/asm/types.h > >> >> > +++ b/arch/riscv/include/asm/types.h > >> >> > @@ -29,7 +29,11 @@ typedef unsigned short umode_t; > >> >> > > >> >> > #include <stddef.h> > >> >> > > >> >> > +#ifdef CONFIG_DMA_ADDR_T_64BIT > >> >> > +typedef u64 dma_addr_t; > >> >> > +#else > >> >> > typedef u32 dma_addr_t; > >> >> > +#endif > >> >> > >> >> Why is this patch needed for U-Boot? > >> >> > >> > > >> > Initially this patch was created for the MACB driver dependency and > now the MACB driver is not dependent on CONFIG_DMA_ADDR_T_64BIT. > >> > But We created this patch the same as the ARM 64-bit kconfig and the > 'CONFIG_DMA_ADDR_T_64BIT' is used when the MMC driver is configured with > DMA. > >> > > >> > >> But in U-Boot there is no 64-bit address. The DMA address should be > >> under 4G. Both MACB and MMC driver should work with the 32-bit DMA > >> addresses, no? > >> > > > > We will use 64-bit addresses in the future. > > But U-Boot does not generate 64-bit addresses for DMA at present. > > PolarFire SoC GEM uses 64-bit DMA not 32-bit DMA Regards Padmarao > > Both MACB and MMC drivers work with 64-bit DMA addresses in the > PolarFire SoC. > > So I think the patch to enable 64-bit DMA in U-Boot is not necessary. > > Regards, > Bin >
