Re: [PATCH] xen: arm: Enable 1:1 workaround by default

[Julien Grall <julien.grall@linaro.org>]

On 11/27/2013 12:19 PM, Ian Campbell wrote:
> I was just about to send out patches adding the 1:1 workaround to vexpress (the
> foundation model is a vexpress platfrom with DMA) and sunxi.
>
> That would have meant that all platforms now implement the quirk. Instead lets
> just make it the default and remove the quirk.
>
> In the future this will likely be set based on the presence absence of an
> IOMMU, perhaps with additional overrides by the platform.
>
> A command line option no-dom0_11_mapping is provided.
>

I plan to use the variable in other place, for instance in 
common/memory.c to solve issue between ballooning and 1:1 workaround.

It would be great if we have a function (platform_has_iommu) that we can 
use everywhere. What do you think?


> Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
> ---
>   xen/arch/arm/domain_build.c      | 5 ++++-
>   xen/arch/arm/platforms/exynos5.c | 6 ------
>   xen/arch/arm/platforms/midway.c  | 6 ------
>   xen/arch/arm/platforms/omap5.c   | 6 ------
>   xen/include/asm-arm/platform.h   | 6 ------
>   5 files changed, 4 insertions(+), 25 deletions(-)
>
> diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
> index e9bb01f..ed22613 100644
> --- a/xen/arch/arm/domain_build.c
> +++ b/xen/arch/arm/domain_build.c
> @@ -22,6 +22,9 @@
>   static unsigned int __initdata opt_dom0_max_vcpus;
>   integer_param("dom0_max_vcpus", opt_dom0_max_vcpus);
>
> +static int opt_dom0_11_mapping = 1;
> +boolean_param("dom0_11_mapping", opt_dom0_11_mapping);
> +
>   #define DOM0_MEM_DEFAULT 0x8000000 /* 128 MiB */
>   static u64 __initdata dom0_mem = DOM0_MEM_DEFAULT;
>
> @@ -110,7 +113,7 @@ static void allocate_memory(struct domain *d, struct kernel_info *kinfo)
>       u32 reg_len, reg_size;
>       unsigned int bank = 0;
>
> -    if ( platform_has_quirk(PLATFORM_QUIRK_DOM0_MAPPING_11) )
> +    if ( opt_dom0_11_mapping )
>           return allocate_memory_11(d, kinfo);
>
>       while ( (memory = dt_find_node_by_type(memory, "memory")) )
> diff --git a/xen/arch/arm/platforms/exynos5.c b/xen/arch/arm/platforms/exynos5.c
> index 0e76cac..fa6b465 100644
> --- a/xen/arch/arm/platforms/exynos5.c
> +++ b/xen/arch/arm/platforms/exynos5.c
> @@ -111,11 +111,6 @@ static void exynos5_reset(void)
>       iounmap(pmu);
>   }
>
> -static uint32_t exynos5_quirks(void)
> -{
> -    return PLATFORM_QUIRK_DOM0_MAPPING_11;
> -}
> -
>   static const char * const exynos5_dt_compat[] __initconst =
>   {
>       "samsung,exynos5250",
> @@ -139,7 +134,6 @@ PLATFORM_START(exynos5, "SAMSUNG EXYNOS5")
>       .smp_init = exynos5_smp_init,
>       .cpu_up = exynos5_cpu_up,
>       .reset = exynos5_reset,
> -    .quirks = exynos5_quirks,
>       .blacklist_dev = exynos5_blacklist_dev,
>   PLATFORM_END
>
> diff --git a/xen/arch/arm/platforms/midway.c b/xen/arch/arm/platforms/midway.c
> index 399056b..b221279 100644
> --- a/xen/arch/arm/platforms/midway.c
> +++ b/xen/arch/arm/platforms/midway.c
> @@ -42,11 +42,6 @@ static void midway_reset(void)
>       iounmap(pmu);
>   }
>
> -static uint32_t midway_quirks(void)
> -{
> -    return PLATFORM_QUIRK_DOM0_MAPPING_11;
> -}
> -
>   static const char * const midway_dt_compat[] __initconst =
>   {
>       "calxeda,ecx-2000",
> @@ -56,7 +51,6 @@ static const char * const midway_dt_compat[] __initconst =
>   PLATFORM_START(midway, "CALXEDA MIDWAY")
>       .compatible = midway_dt_compat,
>       .reset = midway_reset,
> -    .quirks = midway_quirks,
>   PLATFORM_END
>
>   /*
> diff --git a/xen/arch/arm/platforms/omap5.c b/xen/arch/arm/platforms/omap5.c
> index 54fa5ff..3a3b16b 100644
> --- a/xen/arch/arm/platforms/omap5.c
> +++ b/xen/arch/arm/platforms/omap5.c
> @@ -153,11 +153,6 @@ static int __init omap5_cpu_up(int cpu)
>       return 0;
>   }
>
> -static uint32_t omap5_quirks(void)
> -{
> -    return PLATFORM_QUIRK_DOM0_MAPPING_11;
> -}
> -
>   static const char const *omap5_dt_compat[] __initconst =
>   {
>       "ti,omap5",
> @@ -170,7 +165,6 @@ PLATFORM_START(omap5, "TI OMAP5")
>       .specific_mapping = omap5_specific_mapping,
>       .smp_init = omap5_smp_init,
>       .cpu_up = omap5_cpu_up,
> -    .quirks = omap5_quirks,
>   PLATFORM_END
>
>   /*
> diff --git a/xen/include/asm-arm/platform.h b/xen/include/asm-arm/platform.h
> index c282b30..6d108e7 100644
> --- a/xen/include/asm-arm/platform.h
> +++ b/xen/include/asm-arm/platform.h
> @@ -39,12 +39,6 @@ struct platform_desc {
>       const struct dt_device_match *blacklist_dev;
>   };
>
> -/*
> - * Quirk to map dom0 memory in 1:1
> - * Useful on platform where System MMU is not yet implemented
> - */
> -#define PLATFORM_QUIRK_DOM0_MAPPING_11 (1 << 0)
> -
>   void __init platform_init(void);
>   int __init platform_init_time(void);
>   int __init platform_specific_mapping(struct domain *d);
>

-- 
Julien Grall