Re: [PATCH v0 1/2] aspeed: support uart controller both 0 and 1 base

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 5/2/24 11:46, Cédric Le Goater wrote:
> Hello Jamin,
> 
> On 2/5/24 10:14, Jamin Lin wrote:
>> According to the design of ASPEED SOCS, the uart controller
>> is 1 base for ast10x0, ast2600, ast2500 and ast2400.
>>
>> However, the uart controller is 0 base for ast2700.
>> To support uart controller both 0 and 1 base,
>> adds uasrt_bases parameter in AspeedSoCClass
>> and set the default uart controller 1 base
>> for ast10x0, astt2600, ast2500 and ast2400.
> 
> The board definition can set 'amc->uart_default' to choose a different
> default serial port for the console, or use the "bmc-console" machine
> option . Isn't it enough ? May be I am misunderstanding the need.
> 
> To clarify,
> 
> ASPEED_DEV_UART1 is in the first serial port on the boards.
> 
> I think we chose to start the indexing at 1 because the Aspeed QEMU
> modeling began first with the UART model (console) and for simplicity,
> we copied the definitions of the device tree from Linux :
> 
>      serial0 = &uart1;
>      serial1 = &uart2;
>      serial2 = &uart3;
>      serial3 = &uart4;
>      serial4 = &uart5;
>      serial5 = &vuart;
> 
> We replicated this indexing starting at 1 to nearly all device models :
> 
>      ASPEED_DEV_UART1 - 13
>      ASPEED_DEV_SPI1 -2
>      ASPEED_DEV_EHCI1 -2
>      ASPEED_DEV_TIMER1 - 8
>      ASPEED_DEV_ETH1 -4
>      ASPEED_DEV_MII1 - 4
>      ASPEED_DEV_JTAG0 - 1      <--- !!
>      ASPEED_DEV_FSI1 - 2
> 
> I don't know what would be ASPEED_DEV_UART0 in this context.
> 
> May be you could send a simplified AST2700 SoC model with definitions
> of a minimum address space and IRQ space ?

Looking at TF-A definitions,
https://github.com/ARM-software/arm-trusted-firmware/commit/85f199b77447

#define UART_BASE	U(0x14c33000)
#define UART12_BASE	(UART_BASE + 0xb00)
#define CONSOLE_UART_BASE		UART12_BASE

As Cédric described, we have TF-A UART12_BASE -> QEMU ASPEED_DEV_UART13.