Re: [PATCH 1/2] arm64: amd-seattle: Fix dma-ranges property
On Tuesday 02 December 2014 14:12:48 Suthikulpanit, Suravee wrote: > > Would you minding adding the following detail in the commit message? I was going to, but then decided not to. It's usually better if you just send a new patch when requested to update the changelog, so please do that. > - BEGIN - > AMD Seattle supports 40-bit DMA, which includes two ranges: > 1. GICv2m MSI register frame at 0xe008 > 2. DRAM range [0x80 to 0xff] > > Since the current parsing logic handles only single range, this patch > specifies the range from zero to 0x100 to cover the whole > 40-bit range. > > However, it expects DMA allocation/mapping logic to check the specified > DMA range against the reported DRAM range, which starts from > 0x80 in this case. Unfortunately the description is (for the most part) wrong: - It doesn't matter whatsoever what the target of the DMA is or how large the DRAM can be. The only thing that matters is the transformation that the bus physically performs. If the AXI bus is (as you said earlier, though I'm no longer sure about it after your text above) limited to 40 bit address, you should use the 40-bit mask you gave above. If the 40-bit address is not a result of a limitation of the AXI bus but of the memory controller, you should just list a full 64-bit mask here. In that case, you actually have to use '0x 0x' as the length, which is one byte short as before, but we can't express that otherwise. - Furthermore it does not matter at all what the Linux implementation does. If your hardware does a transformation that the current code can't handle, we need to fix the code rather than work around the implementation bug by putting incorrect data into the DT. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 1/2] arm64: amd-seattle: Fix dma-ranges property
On Tuesday 02 December 2014 14:12:48 Suthikulpanit, Suravee wrote: Would you minding adding the following detail in the commit message? I was going to, but then decided not to. It's usually better if you just send a new patch when requested to update the changelog, so please do that. - BEGIN - AMD Seattle supports 40-bit DMA, which includes two ranges: 1. GICv2m MSI register frame at 0xe008 2. DRAM range [0x80 to 0xff] Since the current parsing logic handles only single range, this patch specifies the range from zero to 0x100 to cover the whole 40-bit range. However, it expects DMA allocation/mapping logic to check the specified DMA range against the reported DRAM range, which starts from 0x80 in this case. Unfortunately the description is (for the most part) wrong: - It doesn't matter whatsoever what the target of the DMA is or how large the DRAM can be. The only thing that matters is the transformation that the bus physically performs. If the AXI bus is (as you said earlier, though I'm no longer sure about it after your text above) limited to 40 bit address, you should use the 40-bit mask you gave above. If the 40-bit address is not a result of a limitation of the AXI bus but of the memory controller, you should just list a full 64-bit mask here. In that case, you actually have to use '0x 0x' as the length, which is one byte short as before, but we can't express that otherwise. - Furthermore it does not matter at all what the Linux implementation does. If your hardware does a transformation that the current code can't handle, we need to fix the code rather than work around the implementation bug by putting incorrect data into the DT. Arnd -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 1/2] arm64: amd-seattle: Fix dma-ranges property
Hi Arnd, On 12/1/14, 20:33, "Arnd Bergmann" wrote: >On Sunday 30 November 2014 21:46:39 suravee.suthikulpa...@amd.com wrote: >> From: Suravee Suthikulpanit >> >> AMD Seattle should support 40-bit DMA. >> >> Signed-off-by: Suravee Suthikulpanit >> > >The change looks good, but two things about the patch description: > >- You should be a little more verbose, especially after we had discussed > this to some detail on IRC, explain why you use the specific values. Would you minding adding the following detail in the commit message? - BEGIN - AMD Seattle supports 40-bit DMA, which includes two ranges: 1. GICv2m MSI register frame at 0xe008 2. DRAM range [0x80 to 0xff] Since the current parsing logic handles only single range, this patch specifies the range from zero to 0x100 to cover the whole 40-bit range. However, it expects DMA allocation/mapping logic to check the specified DMA range against the reported DRAM range, which starts from 0x80 in this case. - END - > >- You should configure git-send-email to know your full email address > including the name. Right now it gets sent from > "suravee.suthikulpa...@amd.com" instead of "Suravee Suthikulpanit > ", and that causes the extra From > line at the start of the mail, besides looking a bit strange. Thanks for the pointer. I didn¹t notice that. I¹ll fix that for the future. Suravee > >Thanks, > > Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 1/2] arm64: amd-seattle: Fix dma-ranges property
Hi Arnd, On 12/1/14, 20:33, Arnd Bergmann a...@arndb.de wrote: On Sunday 30 November 2014 21:46:39 suravee.suthikulpa...@amd.com wrote: From: Suravee Suthikulpanit suravee.suthikulpa...@amd.com AMD Seattle should support 40-bit DMA. Signed-off-by: Suravee Suthikulpanit suravee.suthikulpa...@amd.com The change looks good, but two things about the patch description: - You should be a little more verbose, especially after we had discussed this to some detail on IRC, explain why you use the specific values. Would you minding adding the following detail in the commit message? - BEGIN - AMD Seattle supports 40-bit DMA, which includes two ranges: 1. GICv2m MSI register frame at 0xe008 2. DRAM range [0x80 to 0xff] Since the current parsing logic handles only single range, this patch specifies the range from zero to 0x100 to cover the whole 40-bit range. However, it expects DMA allocation/mapping logic to check the specified DMA range against the reported DRAM range, which starts from 0x80 in this case. - END - - You should configure git-send-email to know your full email address including the name. Right now it gets sent from suravee.suthikulpa...@amd.com instead of Suravee Suthikulpanit suravee.suthikulpa...@amd.com, and that causes the extra From line at the start of the mail, besides looking a bit strange. Thanks for the pointer. I didn¹t notice that. I¹ll fix that for the future. Suravee Thanks, Arnd -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 1/2] arm64: amd-seattle: Fix dma-ranges property
On Sunday 30 November 2014 21:46:39 suravee.suthikulpa...@amd.com wrote: > From: Suravee Suthikulpanit > > AMD Seattle should support 40-bit DMA. > > Signed-off-by: Suravee Suthikulpanit > The change looks good, but two things about the patch description: - You should be a little more verbose, especially after we had discussed this to some detail on IRC, explain why you use the specific values. - You should configure git-send-email to know your full email address including the name. Right now it gets sent from "suravee.suthikulpa...@amd.com" instead of "Suravee Suthikulpanit ", and that causes the extra From line at the start of the mail, besides looking a bit strange. Thanks, Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 1/2] arm64: amd-seattle: Fix dma-ranges property
On Sunday 30 November 2014 21:46:39 suravee.suthikulpa...@amd.com wrote: From: Suravee Suthikulpanit suravee.suthikulpa...@amd.com AMD Seattle should support 40-bit DMA. Signed-off-by: Suravee Suthikulpanit suravee.suthikulpa...@amd.com The change looks good, but two things about the patch description: - You should be a little more verbose, especially after we had discussed this to some detail on IRC, explain why you use the specific values. - You should configure git-send-email to know your full email address including the name. Right now it gets sent from suravee.suthikulpa...@amd.com instead of Suravee Suthikulpanit suravee.suthikulpa...@amd.com, and that causes the extra From line at the start of the mail, besides looking a bit strange. Thanks, Arnd -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH 1/2] arm64: amd-seattle: Fix dma-ranges property
From: Suravee Suthikulpanit AMD Seattle should support 40-bit DMA. Signed-off-by: Suravee Suthikulpanit --- arch/arm64/boot/dts/amd/amd-seattle-soc.dtsi | 10 +++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/arm64/boot/dts/amd/amd-seattle-soc.dtsi b/arch/arm64/boot/dts/amd/amd-seattle-soc.dtsi index 0c8e7ae..f370f03 100644 --- a/arch/arm64/boot/dts/amd/amd-seattle-soc.dtsi +++ b/arch/arm64/boot/dts/amd/amd-seattle-soc.dtsi @@ -55,8 +55,12 @@ #size-cells = <2>; ranges; - /* DDR range is 40-bit addressing */ - dma-ranges = <0x80 0x0 0x80 0x0 0x7f 0x>; + /* +* dma-ranges is 40-bit address space containing: +* - GICv2m MSI register is at 0xe008 +* - DRAM range [0x80 to 0xff] +*/ + dma-ranges = <0x0 0x0 0x0 0x0 0x100 0x0>; /include/ "amd-seattle-clks.dtsi" @@ -159,7 +163,7 @@ <0x1000 0x0 0x0 0x4 0x0 0x0 0x0 0x123 0x1>; dma-coherent; - dma-ranges = <0x4300 0x80 0x0 0x80 0x0 0x7f 0x>; + dma-ranges = <0x4300 0x0 0x0 0x0 0x0 0x100 0x0>; ranges = /* I/O Memory (size=64K) */ <0x0100 0x00 0x 0x00 0xefff 0x00 0x0001>, -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH 1/2] arm64: amd-seattle: Fix dma-ranges property
From: Suravee Suthikulpanit suravee.suthikulpa...@amd.com AMD Seattle should support 40-bit DMA. Signed-off-by: Suravee Suthikulpanit suravee.suthikulpa...@amd.com --- arch/arm64/boot/dts/amd/amd-seattle-soc.dtsi | 10 +++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/arm64/boot/dts/amd/amd-seattle-soc.dtsi b/arch/arm64/boot/dts/amd/amd-seattle-soc.dtsi index 0c8e7ae..f370f03 100644 --- a/arch/arm64/boot/dts/amd/amd-seattle-soc.dtsi +++ b/arch/arm64/boot/dts/amd/amd-seattle-soc.dtsi @@ -55,8 +55,12 @@ #size-cells = 2; ranges; - /* DDR range is 40-bit addressing */ - dma-ranges = 0x80 0x0 0x80 0x0 0x7f 0x; + /* +* dma-ranges is 40-bit address space containing: +* - GICv2m MSI register is at 0xe008 +* - DRAM range [0x80 to 0xff] +*/ + dma-ranges = 0x0 0x0 0x0 0x0 0x100 0x0; /include/ amd-seattle-clks.dtsi @@ -159,7 +163,7 @@ 0x1000 0x0 0x0 0x4 gic0 0x0 0x0 0x0 0x123 0x1; dma-coherent; - dma-ranges = 0x4300 0x80 0x0 0x80 0x0 0x7f 0x; + dma-ranges = 0x4300 0x0 0x0 0x0 0x0 0x100 0x0; ranges = /* I/O Memory (size=64K) */ 0x0100 0x00 0x 0x00 0xefff 0x00 0x0001, -- 1.9.3 -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
