From mboxrd@z Thu Jan 1 00:00:00 1970 From: ard.biesheuvel@linaro.org (Ard Biesheuvel) Date: Tue, 22 Sep 2015 17:37:37 -0700 Subject: [PATCH v2 1/7] of/fdt: make memblock minimum physical address arch configurable In-Reply-To: <1442968663-31843-1-git-send-email-ard.biesheuvel@linaro.org> References: <1442968663-31843-1-git-send-email-ard.biesheuvel@linaro.org> Message-ID: <1442968663-31843-2-git-send-email-ard.biesheuvel@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org By default, early_init_dt_add_memory_arch() ignores memory below the base of the kernel image since it won't be addressable via the linear mapping. However, this is not appropriate anymore once we decouple the kernel text mapping from the linear mapping, so archs may want to drop the low limit entirely. So allow the minimum to be overridden by setting MIN_MEMBLOCK_ADDR. Signed-off-by: Ard Biesheuvel --- drivers/of/fdt.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index 6e82bc42373b..5e7ef800a816 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -967,13 +967,16 @@ int __init early_init_dt_scan_chosen(unsigned long node, const char *uname, } #ifdef CONFIG_HAVE_MEMBLOCK +#ifndef MIN_MEMBLOCK_ADDR +#define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET) +#endif #ifndef MAX_MEMBLOCK_ADDR #define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0) #endif void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size) { - const u64 phys_offset = __pa(PAGE_OFFSET); + const u64 phys_offset = MIN_MEMBLOCK_ADDR; if (!PAGE_ALIGNED(base)) { if (size < PAGE_SIZE - (base & ~PAGE_MASK)) { -- 1.9.1