Re: [PATCH 07/15] ARM: dts: Configure interconnect target module for dra7 sata

[Roger Quadros <rogerq@kernel.org>]

On 14/11/2024 15:50, Romain Naour wrote:
> Hi Roger, Robin, All,
> 
> Le 14/11/2024 à 12:02, Roger Quadros a écrit :
>> Hi Romain,
>>
>> On 12/11/2024 16:15, Romain Naour wrote:
>>> Hello Tony, Roger, All,
>>>
>>> Le 26/01/2021 à 13:39, Tony Lindgren a écrit :
>>>> We can now probe devices with device tree only configuration using
>>>> ti-sysc interconnect target module driver. Let's configure the
>>>> module, but keep the legacy "ti,hwmods" peroperty to avoid new boot
>>>> time warnings. The legacy property will be removed in later patches
>>>> together with the legacy platform data.
>>>>
>>>> Note that the old sysc register offset is wrong, the real offset is at
>>>> 0x1100 as listed in TRM for SATA_SYSCONFIG register. Looks like we've been
>>>> happily using sata on the bootloader configured sysconfig register and
>>>> nobody noticed. Also the old register range for SATAMAC_wrapper registers
>>>> is wrong at 7 while it should be 8. But that too seems harmless.
>>>>
>>>> There is also an L3 parent interconnect range that we don't seem to be
>>>> using. That can be added as needed later on.
>>>
>>> Since the switch from a kernel 5.10 to 6.1, the dra7 (AM574x) sata interface
>>> doesn't work as expected.
>>>
>>> Using a kernel 6.1 with a preformated ext4 SATA disc, any copied file will be
>>> corrupted when the filesystem is umounted.
>>>
>>> mount /dev/sda1 /mnt
>>> cp /<test_file> /mnt/
>>> sync
>>> sha256sum /mnt/<test_file> /<test_file>
>>> <same hash>
>>> umount /mnt
>>>
>>> mount /dev/sda1 /mnt
>>> sha256sum /mnt/<test_file> /<test_file>
>>> /mnt/<test_file> is corrupted.
>>>
>>> git bisect report 8af15365a368 ("ARM: dts: Configure interconnect target module
>>> for dra7 sata") as the first bad commit [1] (merged in 5.13).
>>>
>>> While looking for existing SATA issue on dra7 SoC, I found this old patch:
>>>
>>> "On TI Platforms using LPAE, SATA breaks with 64-bit DMA. Restrict it to
>>> 32-bit." [2].
>>>
>>> Even if it's not the correct fix, disabling 64-bit DMA allows to use the sata
>>> disc correctly. The discussion about this issue seems to have stopped [3] and
>>> the suggested change was never merged.
>>
>> If I remember right the following commit fixed the issue back then.
>>
>> cfb5d65f2595 ARM: dts: dra7: Add bus_dma_limit for L3 bus
>>
>> But, when commit [1] moved the SATA node from L3 bus to L4_cfg it lost the bus_dma_limit
>> that we added at the L3 bus and hence the regression.
>>
>> I think we should add the same 2GB dma ranges limit into l4_cfg bus so all modules
>> can inherit it.
> 
> Thanks for your reply!
> 
> It seems l4_cfg can inherit dma-ranges property from ocp node using
> "dma-ranges;". But then segment@100000 node (0x4a100000) needs "dma-ranges;" too.
> 
> With the following patch applied, the SATA drive works correctly.
> 
> diff --git a/arch/arm/boot/dts/dra7-l4.dtsi b/arch/arm/boot/dts/dra7-l4.dtsi
> index 1aaffd034c39..3ac770298844 100644
> --- a/arch/arm/boot/dts/dra7-l4.dtsi
> +++ b/arch/arm/boot/dts/dra7-l4.dtsi
> @@ -12,6 +12,7 @@ &l4_cfg {                                             /*
> 0x4a000000 */
>         ranges = <0x00000000 0x4a000000 0x100000>,      /* segment 0 */
>                  <0x00100000 0x4a100000 0x100000>,      /* segment 1 */
>                  <0x00200000 0x4a200000 0x100000>;      /* segment 2 */
> +       dma-ranges;
> 
>         segment@0 {                                     /* 0x4a000000 */
>                 compatible = "simple-pm-bus";
> @@ -557,6 +558,7 @@ segment@100000 {                                    /*
> 0x4a100000 */
>                          <0x0007e000 0x0017e000 0x001000>,      /* ap 124 */
>                          <0x00059000 0x00159000 0x001000>,      /* ap 125 */
>                          <0x0005a000 0x0015a000 0x001000>;      /* ap 126 */
> +               dma-ranges;
> 
>                 target-module@2000 {                    /* 0x4a102000, ap 27 3c.0 */
>                         compatible = "ti,sysc";
> 
> 
> Sorry, I'm not familliar with property inheritance between devicetree nodes,
> especially with dma-ranges. Does this change seem correct to you?

I think this is correct.
A similar fix [4] was done for PCIe as well.

[4] https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=90d4d3f4ea45370d482fa609dbae4d2281b4074f

> 
> Best regards,
> Romain
> 
> 
>>
>>>
>>> The SATA port is unlikely not available on TI AM57 EVM boards or the beaglebone-AI.
>>>
>>> Any suggestion?
>>>
>>> [1]
>>> https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=8af15365a36845c4c15d4c8046ddccff331d5263
>>> [2] https://lore.kernel.org/all/20200206111728.6703-1-rogerq@ti.com/T/
>>> [3] https://lore.kernel.org/lkml/c753a232-403d-6ed2-89fd-09476c887391@ti.com/
>>>
>>> Best regards,
>>> Romain
>>>
>>>
>>>>
>>>> Signed-off-by: Tony Lindgren <tony@atomide.com>
>>>> ---
>>>>  arch/arm/boot/dts/dra7-l4.dtsi | 29 ++++++++++++++++++++++++++---
>>>>  arch/arm/boot/dts/dra7.dtsi    | 12 ------------
>>>>  2 files changed, 26 insertions(+), 15 deletions(-)
>>>>
>>>> diff --git a/arch/arm/boot/dts/dra7-l4.dtsi b/arch/arm/boot/dts/dra7-l4.dtsi
>>>> --- a/arch/arm/boot/dts/dra7-l4.dtsi
>>>> +++ b/arch/arm/boot/dts/dra7-l4.dtsi
>>>> @@ -572,11 +572,34 @@ target-module@8000 {			/* 0x4a108000, ap 29 1e.0 */
>>>>  		};
>>>>  
>>>>  		target-module@40000 {			/* 0x4a140000, ap 31 06.0 */
>>>> -			compatible = "ti,sysc";
>>>> -			status = "disabled";
>>>> -			#address-cells = <1>;
>>>> +			compatible = "ti,sysc-omap4", "ti,sysc";
>>>> +			ti,hwmods = "sata";
>>>> +			reg = <0x400fc 4>,
>>>> +			      <0x41100 4>;
>>>> +			reg-names = "rev", "sysc";
>>>> +			ti,sysc-midle = <SYSC_IDLE_FORCE>,
>>>> +					<SYSC_IDLE_NO>,
>>>> +					<SYSC_IDLE_SMART>;
>>>> +			ti,sysc-sidle = <SYSC_IDLE_FORCE>,
>>>> +					<SYSC_IDLE_NO>,
>>>> +					<SYSC_IDLE_SMART>,
>>>> +					<SYSC_IDLE_SMART_WKUP>;
>>>> +			power-domains = <&prm_l3init>;
>>>> +			clocks = <&l3init_clkctrl DRA7_L3INIT_SATA_CLKCTRL 0>;
>>>> +			clock-names = "fck";
>>>>  			#size-cells = <1>;
>>>> +			#address-cells = <1>;
>>>>  			ranges = <0x0 0x40000 0x10000>;
>>>> +
>>>> +			sata: sata@0 {
>>>> +				compatible = "snps,dwc-ahci";
>>>> +				reg = <0 0x1100>, <0x1100 0x8>;
>>>> +				interrupts = <GIC_SPI 49 IRQ_TYPE_LEVEL_HIGH>;
>>>> +				phys = <&sata_phy>;
>>>> +				phy-names = "sata-phy";
>>>> +				clocks = <&l3init_clkctrl DRA7_L3INIT_SATA_CLKCTRL 8>;
>>>> +				ports-implemented = <0x1>;
>>>> +			};
>>>>  		};
>>>>  
>>>>  		target-module@51000 {			/* 0x4a151000, ap 33 50.0 */
>>>> diff --git a/arch/arm/boot/dts/dra7.dtsi b/arch/arm/boot/dts/dra7.dtsi
>>>> --- a/arch/arm/boot/dts/dra7.dtsi
>>>> +++ b/arch/arm/boot/dts/dra7.dtsi
>>>> @@ -785,18 +785,6 @@ qspi: spi@0 {
>>>>  			};
>>>>  		};
>>>>  
>>>> -		/* OCP2SCP3 */
>>>> -		sata: sata@4a141100 {
>>>> -			compatible = "snps,dwc-ahci";
>>>> -			reg = <0x4a140000 0x1100>, <0x4a141100 0x7>;
>>>> -			interrupts = <GIC_SPI 49 IRQ_TYPE_LEVEL_HIGH>;
>>>> -			phys = <&sata_phy>;
>>>> -			phy-names = "sata-phy";
>>>> -			clocks = <&l3init_clkctrl DRA7_L3INIT_SATA_CLKCTRL 8>;
>>>> -			ti,hwmods = "sata";
>>>> -			ports-implemented = <0x1>;
>>>> -		};
>>>> -
>>>>  		/* OCP2SCP1 */
>>>>  		/* IRQ for DWC3_3 and DWC3_4 need IRQ crossbar */
>>>>  
>>
> 

-- 
cheers,
-roger