Re: [PATCH] arm64: dts: meson: fix g12a buses

From: Jianxin Pan
Date: Fri Jan 18 2019 - 13:09:23 EST

Hi Martin and Jerome,

On 2019/1/18 5:20, Martin Blumenstingl wrote:
> On Thu, Jan 17, 2019 at 9:39 PM Jerome Brunet <jbrunet@xxxxxxxxxxxx> wrote:
>> On Thu, 2019-01-17 at 21:27 +0100, Martin Blumenstingl wrote:
>>> OK, but we had incorrect documentation in the past. did you check this
>>> with someone from Amlogic?
>>> I'm curious because there seem to be two different approaches here:
>>> 1) hiubus name and offsets are being fixed within this patch
>>> 2) aobus is being dropped here and re-introduced with a different name later
>>> on
>> because hiu exist and aobus does not, for which both the name and size was
>> wrong
>>> approach 1) can also be used for the "rti" region (at least in my
>>> opinion, the patch doesn't explain why it can't be done):
>> THe patch remove aobus (instead of fixing name and size) because, of the
>> multiple region documented covered by this 'made region', I did not anticipate
>> which one will be required and I did not want to add them all.
>> Better to add them as needed, which is want I done for pinctrl as you pointed
>> out
>>> rename "aobus" to "rti" and change the size to either 0x1000 or 0xb000
>>> (both values can be found in mesong12a.dtsi from
>>> buildroot_openlinux_kernel_4.9_fbdev_20180706)
>> RTI is added here:
>> I don't really understand the problem ? result is the same
> the actual problem is "me" as I have conflicting information:
> - Amlogic's buildroot kernel (for G12A) uses similar bus definitions
> as the GX SoCs (for which there are public datasheets) - this is how
> Jianxin added it to meson-g12a.dtsi originally
> - this patch does it different - but cannot check if this is correct
> (no public datasheet is available for G12A or AXG) nor do I have a
> "big picture" of upcoming changes
> Cc'ing Jianxin: can you please review Jerome's patch and give some
> more details on the memory map on G12A so further contributions can be
> reviewed easier?
1. "aobus: bus@ff800000" describes the following registers:
ahb ao_reg reserved 980 FF80B000
ahb ao_reg ao_mailbox 4 FF80A000
ahb ao_reg sar_adc 4 FF809000
ahb ao_reg ir_dec 4 FF808000
ahb ao_reg pwm_ab 4 FF807000
ahb ao_reg i2c_s 4 FF806000
ahb ao_reg i2c_m 4 FF805000
ahb ao_reg uart2 4 FF804000
ahb ao_reg uart 4 FF803000
ahb ao_reg pwm_cd 4 FF802000
ahb ao_reg reserved 4 FF801000
ahb ao_reg rti 4 FF800000

2. "cbus: bus@ffd00000" describes the following registers:
capb3 cbus reserved 872 FFD26000 FFDFFFFF
capb3 cbus sc 4 FFD25000 FFD25FFF
capb3 cbus uart0 4 FFD24000 FFD24FFF
capb3 cbus uart1 4 FFD23000 FFD23FFF
capb3 cbus uart2 4 FFD22000 FFD22FFF
capb3 cbus reserved 4 FFD21000 FFD21FFF
capb3 cbus reserved 4 FFD20000 FFD20FFF
capb3 cbus i2c_m0 4 FFD1F000 FFD1FFFF
capb3 cbus i2c_m1 4 FFD1E000 FFD1EFFF
capb3 cbus i2c_m2 4 FFD1D000 FFD1DFFF
capb3 cbus i2c_m3 4 FFD1C000 FFD1CFFF
capb3 cbus pwm_ab 4 FFD1B000 FFD1BFFF
capb3 cbus pwm_cd 4 FFD1A000 FFD1AFFF
capb3 cbus pwm_ef 4 FFD19000 FFD19FFF
capb3 cbus msr_clk 4 FFD18000 FFD18FFF
capb3 cbus reserved 4 FFD17000 FFD17FFF
capb3 cbus reserved 4 FFD16000 FFD16FFF
capb3 cbus spicc_1 4 FFD15000 FFD15FFF
capb3 cbus spifc 4 FFD14000 FFD14FFF
capb3 cbus spicc_0 4 FFD13000 FFD13FFF
capb3 cbus reserved 4 FFD12000 FFD12FFF
capb3 cbus reserved 4 FFD11000 FFD11FFF
capb3 cbus reserved 4 FFD10000 FFD10FFF
capb3 cbus isa 4 FFD0F000 FFD0FFFF
capb3 cbus parser 4 FFD0E000 FFD0EFFF
capb3 cbus reserved 4 FFD0D000 FFD0DFFF
capb3 cbus sana 4 FFD0C000 FFD0CFFF
capb3 cbus stream 4 FFD0B000 FFD0BFFF
capb3 cbus async_fifo 4 FFD0A000 FFD0AFFF
capb3 cbus async_fifo2 4 FFD09000 FFD09FFF
capb3 cbus assist 4 FFD08000 FFD08FFF
capb3 cbus mipi_dsi_host 4 FFD07000 FFD07FFF
capb3 cbus stb 4 FFD06000 FFD06FFF
capb3 cbus aififo 4 FFD05000 FFD05FFF
capb3 cbus reserved 4 FFD04000 FFD04FFF
capb3 cbus reserved 4 FFD03000 FFD03FFF
capb3 cbus reserved 4 FFD02000 FFD02FFF
capb3 cbus reset 4 FFD01000 FFD01FFF
capb3 cbus reserved 4 FFD00000 FFD00FFF

3. In public data sheet, I can only found memory map about sub-regions of each bus.
And no information about the bus itself.

> Regards
> Martin
> .