From 716777db7270255f1f7210fd87a7188b08c9a267 Mon Sep 17 00:00:00 2001 From: Magnus Damm <damm@igel.co.jp> Date: Tue, 25 Nov 2008 21:57:29 +0900 Subject: sh: P4 ioremap pass-through This patch adds a pass-through case when ioremapping P4 addresses. Addresses passed to ioremap() should be physical addresses, so the best option is usually to convert the virtual address to a physical address before calling ioremap. This will give you a virtual address in P2 which matches the physical address and this works well for most internal hardware blocks on the SuperH architecture. However, some hardware blocks must be accessed through P4. Converting the P4 address to a physical and then back to a P2 does not work. One example of this is the sh7722 TMU block, it must be accessed through P4. Without this patch P4 addresses will be mapped using PTEs which requires the page allocator to be up and running. Signed-off-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org> --- arch/sh/include/asm/addrspace.h | 11 +++++++++++ arch/sh/include/asm/io.h | 4 ++++ 2 files changed, 15 insertions(+) (limited to 'arch/sh/include/asm') diff --git a/arch/sh/include/asm/addrspace.h b/arch/sh/include/asm/addrspace.h index 2702d81..36736c7 100644 --- a/arch/sh/include/asm/addrspace.h +++ b/arch/sh/include/asm/addrspace.h @@ -49,5 +49,16 @@ /* Check if an address can be reached in 29 bits */ #define IS_29BIT(a) (((unsigned long)(a)) < 0x20000000) +#ifdef CONFIG_SH_STORE_QUEUES +/* + * This is a special case for the SH-4 store queues, as pages for this + * space still need to be faulted in before it's possible to flush the + * store queue cache for writeout to the remapped region. + */ +#define P3_ADDR_MAX (P4SEG_STORE_QUE + 0x04000000) +#else +#define P3_ADDR_MAX P4SEG +#endif + #endif /* __KERNEL__ */ #endif /* __ASM_SH_ADDRSPACE_H */ diff --git a/arch/sh/include/asm/io.h b/arch/sh/include/asm/io.h index 65eaae3..61f6dae 100644 --- a/arch/sh/include/asm/io.h +++ b/arch/sh/include/asm/io.h @@ -260,6 +260,10 @@ __ioremap_mode(unsigned long offset, unsigned long size, unsigned long flags) return (void __iomem *)P2SEGADDR(offset); } + + /* P4 above the store queues are always mapped. */ + if (unlikely(offset >= P3_ADDR_MAX)) + return (void __iomem *)P4SEGADDR(offset); #endif return __ioremap(offset, size, flags); -- cgit v1.1