[PATCH 4/5] ARM: vexpress: Initial RS1 memory map support

[dave.martin@linaro.org (Dave Martin)]

On Fri, Nov 11, 2011 at 06:27:05PM +0000, Pawel Moll wrote:
> This patch adds support for RS1 memory map based Versatile Express
> motherboard. As the RAM location has changed, the ZRE values and
> PLAT_PHYS_OFFSET defaults are changed to the new address (all
> future tiles will use RS1 map) and enforces AUTO_ZRELADD and
> ARM_PATCH_PHYS_VIRT when legacy devices are being used.
> 
> Signed-off-by: Pawel Moll <pawel.moll@arm.com>
> ---
>  arch/arm/boot/dts/vexpress-v2m-rs1.dtsi           |  190 +++++++++++++++++++++
>  arch/arm/mach-vexpress/Kconfig                    |    9 +
>  arch/arm/mach-vexpress/Makefile.boot              |    6 +-
>  arch/arm/mach-vexpress/include/mach/debug-macro.S |   37 ++++-
>  arch/arm/mach-vexpress/include/mach/uncompress.h  |   13 ++-
>  arch/arm/mach-vexpress/v2m.c                      |   46 +++++
>  6 files changed, 293 insertions(+), 8 deletions(-)
>  create mode 100644 arch/arm/boot/dts/vexpress-v2m-rs1.dtsi

[...]

> diff --git a/arch/arm/mach-vexpress/Kconfig b/arch/arm/mach-vexpress/Kconfig
> index 4c11e90..d1b0f35 100644
> --- a/arch/arm/mach-vexpress/Kconfig
> +++ b/arch/arm/mach-vexpress/Kconfig
> @@ -1,6 +1,14 @@
>  menu "Versatile Express platform type"
>  	depends on ARCH_VEXPRESS
> +config ARCH_VEXPRESS_LEGACY

Brief comment explaining what this is?

> +	bool
> +	select AUTO_ZRELADDR
> +	select ARM_PATCH_PHYS_VIRT
> +
> +config ARCH_VEXPRESS_RS1

Ditto

> +	bool
> +
>  config ARCH_VEXPRESS_CA9X4
>  	bool "Versatile Express Cortex-A9x4 tile"
>  	select CPU_V7
> @@ -8,6 +16,7 @@ config ARCH_VEXPRESS_CA9X4
>  	select ARM_ERRATA_720789
>  	select ARM_ERRATA_751472
>  	select ARM_ERRATA_753970
> +	select ARCH_VEXPRESS_LEGACY

We should add a brief note to the help text explaining the existence
of the new combined A9x4/A5x2 DT based support, if were planning to
keep both variants.  (Probably wise for now, since people may be
temporarily stuck old bootloaders etc.)

If there is no help text yet, we should add some, but it should be
kept brief.

[...]

> diff --git a/arch/arm/mach-vexpress/include/mach/debug-macro.S b/arch/arm/mach-vexpress/include/mach/debug-macro.S
> index fd9e6c7..adc94ce 100644
> --- a/arch/arm/mach-vexpress/include/mach/debug-macro.S
> +++ b/arch/arm/mach-vexpress/include/mach/debug-macro.S
> @@ -10,12 +10,41 @@
>   * published by the Free Software Foundation.
>   */
>  
> -#define DEBUG_LL_UART_OFFSET	0x00009000
> +#define VEXPRESS_PHYS_BASE_LEGACY	0x10000000
> +#define VEXPRESS_UART_OFFSET_LEGACY	0x00009000
> +
> +#define VEXPRESS_PHYS_BASE_RS1		0x1c000000
> +#define VEXPRESS_UART_OFFSET_RS1	0x00090000
> +
> +#define VEXPRESS_VIRT_BASE		0xf8000000
>  
>  		.macro	addruart,rp,rv,tmp
> -		mov	\rp, #DEBUG_LL_UART_OFFSET
> -		orr	\rv, \rp, #0xf8000000	@ virtual base
> -		orr	\rp, \rp, #0x10000000	@ physical base
> +
> +		@ Check the MMU state
> +#if defined(CONFIG_MMU)
> +		mrc	p15, 0, \tmp, c1, c0	@ SCTRL
> +		tst	\tmp, #1		@ MMU enabled?
> +		moveq	\tmp, #VEXPRESS_PHYS_BASE_LEGACY
> +		movne	\tmp, #VEXPRESS_VIRT_BASE
> +#else
> +		mov	\tmp, #VEXPRESS_PHYS_BASE_LEGACY
> +#endif
> +
> +		@ PL011 present in "legacy place"?
> +		orr	\tmp, \tmp, #VEXPRESS_UART_OFFSET_LEGACY
> +		ldr	\tmp, [\tmp, #0xfe0]	@ PeriphID0
> +		teq	\tmp, #0x11		@ PL011
> +
> +		@ Legacy memory map
> +		moveq	\rp, #VEXPRESS_UART_OFFSET_LEGACY
> +		orreq	\rv, \rp, #VEXPRESS_VIRT_BASE
> +		orreq	\rp, \rp, #VEXPRESS_PHYS_BASE_LEGACY
> +
> +		@ RS1 memory map
> +		movne	\rp, #VEXPRESS_UART_OFFSET_RS1
> +		orrne	\rv, \rp, #VEXPRESS_VIRT_BASE
> +		orrne	\rp, \rp, #VEXPRESS_PHYS_BASE_RS1

I will assume that this works :)

Without grokking the detail, it looks fairly reasonable.

[...]

> diff --git a/arch/arm/mach-vexpress/v2m.c b/arch/arm/mach-vexpress/v2m.c

[...]

>  void __init v2m_dt_init_early(void)
> @@ -601,6 +643,10 @@ static struct of_dev_auxdata v2m_dt_auxdata_lookup[] __initdata = {
>  	OF_DEV_AUXDATA("arm,vexpress-flash", V2M_NOR0, "physmap-flash",
>  			&v2m_flash_data),
>  	OF_DEV_AUXDATA("arm,primecell", V2M_MMCI, "mb:mmci", &v2m_mmci_data),
> +	/* RS1 memory map */
> +	OF_DEV_AUXDATA("arm,vexpress-flash", 0x08000000, "physmap-flash",
> +			&v2m_flash_data),
> +	OF_DEV_AUXDATA("arm,primecell", 0x1c050000, "mb:mmci", &v2m_mmci_data),

Can we have macros instead of the magic numbers here?

Cheers
---Dave