From 9ed68785f7f2b001a6911d64fbd10cfc6fa49b27 Mon Sep 17 00:00:00 2001 From: Eugeniy Paltsev Date: Tue, 15 Aug 2017 21:13:54 +0300 Subject: [PATCH] ARC: mm: Decouple RAM base address from kernel link address [Needed for HSDK] Currently the first page of system (hence RAM base) is assumed to be @ CONFIG_LINUX_LINK_BASE, where kernel itself is linked. However is case of HSDK platform, for reasons explained in that patch, this is not true. kernel needs to be linked @ 0x9000_0000 while DDR is still wired at 0x8000_0000. To properly account for this 256M of RAM, we need to introduce a new option and base page frame accountiing off of it. Signed-off-by: Eugeniy Paltsev Signed-off-by: Vineet Gupta [vgupta: renamed CONFIG_KERNEL_RAM_BASE_ADDRESS => CONFIG_LINUX_RAM_BASE : simplified changelog] --- arch/arc/Kconfig | 10 +++++++++- arch/arc/boot/dts/axc001.dtsi | 2 +- arch/arc/boot/dts/axc003.dtsi | 2 +- arch/arc/boot/dts/axc003_idu.dtsi | 2 +- arch/arc/boot/dts/nsim_hs.dts | 2 +- arch/arc/include/asm/page.h | 2 +- arch/arc/mm/cache.c | 2 +- arch/arc/mm/init.c | 6 +++--- 8 files changed, 18 insertions(+), 10 deletions(-) diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index 7db85ab00c52..65b7549e17db 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -418,7 +418,7 @@ endif # ISA_ARCV2 endmenu # "ARC CPU Configuration" config LINUX_LINK_BASE - hex "Linux Link Address" + hex "Kernel link address" default "0x80000000" help ARC700 divides the 32 bit phy address space into two equal halves @@ -431,6 +431,14 @@ config LINUX_LINK_BASE If you don't know what the above means, leave this setting alone. This needs to match memory start address specified in Device Tree +config LINUX_RAM_BASE + hex "RAM base address" + default LINUX_LINK_BASE + help + By default Linux is linked at base of RAM. However in some special + cases (such as HSDK), Linux can't be linked at start of DDR, hence + this option. + config HIGHMEM bool "High Memory Support" select ARCH_DISCONTIGMEM_ENABLE diff --git a/arch/arc/boot/dts/axc001.dtsi b/arch/arc/boot/dts/axc001.dtsi index a380ffa1a458..fdc266504ada 100644 --- a/arch/arc/boot/dts/axc001.dtsi +++ b/arch/arc/boot/dts/axc001.dtsi @@ -99,7 +99,7 @@ memory { device_type = "memory"; - /* CONFIG_KERNEL_RAM_BASE_ADDRESS needs to match low mem start */ + /* CONFIG_LINUX_RAM_BASE needs to match low mem start */ reg = <0x0 0x80000000 0x0 0x1b000000>; /* (512 - 32) MiB */ }; diff --git a/arch/arc/boot/dts/axc003.dtsi b/arch/arc/boot/dts/axc003.dtsi index dca7e39409be..4e6e9f57e790 100644 --- a/arch/arc/boot/dts/axc003.dtsi +++ b/arch/arc/boot/dts/axc003.dtsi @@ -109,7 +109,7 @@ memory { device_type = "memory"; - /* CONFIG_KERNEL_RAM_BASE_ADDRESS needs to match low mem start */ + /* CONFIG_LINUX_RAM_BASE needs to match low mem start */ reg = <0x0 0x80000000 0x0 0x20000000 /* 512 MiB low mem */ 0x1 0xc0000000 0x0 0x40000000>; /* 1 GiB highmem */ }; diff --git a/arch/arc/boot/dts/axc003_idu.dtsi b/arch/arc/boot/dts/axc003_idu.dtsi index 5b56beffc1c5..63954a8b0100 100644 --- a/arch/arc/boot/dts/axc003_idu.dtsi +++ b/arch/arc/boot/dts/axc003_idu.dtsi @@ -115,7 +115,7 @@ memory { device_type = "memory"; - /* CONFIG_KERNEL_RAM_BASE_ADDRESS needs to match low mem start */ + /* CONFIG_LINUX_RAM_BASE needs to match low mem start */ reg = <0x0 0x80000000 0x0 0x20000000 /* 512 MiB low mem */ 0x1 0xc0000000 0x0 0x40000000>; /* 1 GiB highmem */ }; diff --git a/arch/arc/boot/dts/nsim_hs.dts b/arch/arc/boot/dts/nsim_hs.dts index 3772c40c245e..8d787b251f73 100644 --- a/arch/arc/boot/dts/nsim_hs.dts +++ b/arch/arc/boot/dts/nsim_hs.dts @@ -18,7 +18,7 @@ memory { device_type = "memory"; - /* CONFIG_LINUX_LINK_BASE needs to match low mem start */ + /* CONFIG_LINUX_RAM_BASE needs to match low mem start */ reg = <0x0 0x80000000 0x0 0x20000000 /* 512 MB low mem */ 0x1 0x00000000 0x0 0x40000000>; /* 1 GB highmem */ }; diff --git a/arch/arc/include/asm/page.h b/arch/arc/include/asm/page.h index 296c3426a6ad..109baa06831c 100644 --- a/arch/arc/include/asm/page.h +++ b/arch/arc/include/asm/page.h @@ -85,7 +85,7 @@ typedef pte_t * pgtable_t; */ #define virt_to_pfn(kaddr) (__pa(kaddr) >> PAGE_SHIFT) -#define ARCH_PFN_OFFSET virt_to_pfn(CONFIG_LINUX_LINK_BASE) +#define ARCH_PFN_OFFSET virt_to_pfn(CONFIG_LINUX_RAM_BASE) #ifdef CONFIG_FLATMEM #define pfn_valid(pfn) (((pfn) - ARCH_PFN_OFFSET) < max_mapnr) diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c index d68d36c15909..eee924dfffa6 100644 --- a/arch/arc/mm/cache.c +++ b/arch/arc/mm/cache.c @@ -1173,7 +1173,7 @@ noinline void __init arc_ioc_setup(void) write_aux_reg(ARC_REG_IO_COH_AP0_SIZE, order_base_2(mem_sz >> 10) - 2); /* for now assume kernel base is start of IOC aperture */ - ioc_base = CONFIG_LINUX_LINK_BASE; + ioc_base = CONFIG_LINUX_RAM_BASE; if (ioc_base % mem_sz != 0) panic("IOC Aperture start must be aligned to the size of the aperture"); diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c index 8c9415ed6280..ba145065c579 100644 --- a/arch/arc/mm/init.c +++ b/arch/arc/mm/init.c @@ -26,7 +26,7 @@ pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE); char empty_zero_page[PAGE_SIZE] __aligned(PAGE_SIZE); EXPORT_SYMBOL(empty_zero_page); -static const unsigned long low_mem_start = CONFIG_LINUX_LINK_BASE; +static const unsigned long low_mem_start = CONFIG_LINUX_RAM_BASE; static unsigned long low_mem_sz; #ifdef CONFIG_HIGHMEM @@ -63,7 +63,7 @@ void __init early_init_dt_add_memory_arch(u64 base, u64 size) if (!low_mem_sz) { if (base != low_mem_start) - panic("CONFIG_LINUX_LINK_BASE != DT memory { }"); + panic("CONFIG_LINUX_RAM_BASE != DT memory { }"); low_mem_sz = size; in_use = 1; @@ -161,7 +161,7 @@ void __init setup_arch_memory(void) * We can't use the helper free_area_init(zones[]) because it uses * PAGE_OFFSET to compute the @min_low_pfn which would be wrong * when our kernel doesn't start at PAGE_OFFSET, i.e. - * PAGE_OFFSET != CONFIG_LINUX_LINK_BASE + * PAGE_OFFSET != CONFIG_LINUX_RAM_BASE */ free_area_init_node(0, /* node-id */ zones_size, /* num pages per zone */