xtensa: nommu support
Add support for !CONFIG_MMU setups.
Signed-off-by: Johannes Weiner <jw@emlix.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
diff --git a/arch/xtensa/include/asm/cacheflush.h b/arch/xtensa/include/asm/cacheflush.h
index 94c4c53..8fc1c0c 100644
--- a/arch/xtensa/include/asm/cacheflush.h
+++ b/arch/xtensa/include/asm/cacheflush.h
@@ -65,13 +65,17 @@
# define __flush_invalidate_dcache_range(p,s) __invalidate_dcache_range(p,s)
#endif
-#if (DCACHE_WAY_SIZE > PAGE_SIZE)
+#if defined(CONFIG_MMU) && (DCACHE_WAY_SIZE > PAGE_SIZE)
extern void __flush_invalidate_dcache_page_alias(unsigned long, unsigned long);
+#else
+static inline void __flush_invalidate_dcache_page_alias(unsigned long virt,
+ unsigned long phys) { }
#endif
-#if (ICACHE_WAY_SIZE > PAGE_SIZE)
+#if defined(CONFIG_MMU) && (ICACHE_WAY_SIZE > PAGE_SIZE)
extern void __invalidate_icache_page_alias(unsigned long, unsigned long);
#else
-# define __invalidate_icache_page_alias(v,p) do { } while(0)
+static inline void __invalidate_icache_page_alias(unsigned long virt,
+ unsigned long phys) { }
#endif
/*
diff --git a/arch/xtensa/include/asm/dma.h b/arch/xtensa/include/asm/dma.h
index e30f3ab..137ca39 100644
--- a/arch/xtensa/include/asm/dma.h
+++ b/arch/xtensa/include/asm/dma.h
@@ -44,8 +44,9 @@
* the value desired).
*/
+#ifndef MAX_DMA_ADDRESS
#define MAX_DMA_ADDRESS (PAGE_OFFSET + XCHAL_KIO_SIZE - 1)
-
+#endif
/* Reserve and release a DMA channel */
extern int request_dma(unsigned int dmanr, const char * device_id);
diff --git a/arch/xtensa/include/asm/io.h b/arch/xtensa/include/asm/io.h
index 07b7299..d04cd3a 100644
--- a/arch/xtensa/include/asm/io.h
+++ b/arch/xtensa/include/asm/io.h
@@ -69,21 +69,28 @@
static inline void *ioremap(unsigned long offset, unsigned long size)
{
+#ifdef CONFIG_MMU
if (offset >= XCHAL_KIO_PADDR
&& offset < XCHAL_KIO_PADDR + XCHAL_KIO_SIZE)
return (void*)(offset-XCHAL_KIO_PADDR+XCHAL_KIO_BYPASS_VADDR);
-
else
BUG();
+#else
+ return (void *)offset;
+#endif
}
static inline void *ioremap_nocache(unsigned long offset, unsigned long size)
{
+#ifdef CONFIG_MMU
if (offset >= XCHAL_KIO_PADDR
&& offset < XCHAL_KIO_PADDR + XCHAL_KIO_SIZE)
return (void*)(offset-XCHAL_KIO_PADDR+XCHAL_KIO_CACHED_VADDR);
else
BUG();
+#else
+ return (void *)offset;
+#endif
}
static inline void iounmap(void *addr)
diff --git a/arch/xtensa/include/asm/mmu.h b/arch/xtensa/include/asm/mmu.h
index 44c5bb0..04890d6 100644
--- a/arch/xtensa/include/asm/mmu.h
+++ b/arch/xtensa/include/asm/mmu.h
@@ -11,7 +11,12 @@
#ifndef _XTENSA_MMU_H
#define _XTENSA_MMU_H
+#ifndef CONFIG_MMU
+#include <asm/nommu.h>
+#else
+
/* Default "unsigned long" context */
typedef unsigned long mm_context_t;
+#endif /* CONFIG_MMU */
#endif /* _XTENSA_MMU_H */
diff --git a/arch/xtensa/include/asm/mmu_context.h b/arch/xtensa/include/asm/mmu_context.h
index 6b7c19c..dbd8731 100644
--- a/arch/xtensa/include/asm/mmu_context.h
+++ b/arch/xtensa/include/asm/mmu_context.h
@@ -13,6 +13,10 @@
#ifndef _XTENSA_MMU_CONTEXT_H
#define _XTENSA_MMU_CONTEXT_H
+#ifndef CONFIG_MMU
+#include <asm/nommu_context.h>
+#else
+
#include <linux/stringify.h>
#include <linux/sched.h>
@@ -133,4 +137,5 @@
}
+#endif /* CONFIG_MMU */
#endif /* _XTENSA_MMU_CONTEXT_H */
diff --git a/arch/xtensa/include/asm/nommu.h b/arch/xtensa/include/asm/nommu.h
new file mode 100644
index 0000000..dce2c43
--- /dev/null
+++ b/arch/xtensa/include/asm/nommu.h
@@ -0,0 +1,3 @@
+typedef struct {
+ unsigned long end_brk;
+} mm_context_t;
diff --git a/arch/xtensa/include/asm/nommu_context.h b/arch/xtensa/include/asm/nommu_context.h
new file mode 100644
index 0000000..599e7a2
--- /dev/null
+++ b/arch/xtensa/include/asm/nommu_context.h
@@ -0,0 +1,25 @@
+static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
+{
+}
+
+static inline int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
+{
+ return 0;
+}
+
+static inline void destroy_context(struct mm_struct *mm)
+{
+}
+
+static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
+{
+}
+
+static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
+ struct task_struct *tsk)
+{
+}
+
+static inline void deactivate_mm(struct task_struct *tsk, struct mm_struct *mm)
+{
+}
diff --git a/arch/xtensa/include/asm/page.h b/arch/xtensa/include/asm/page.h
index a5a5d33..17e0c53 100644
--- a/arch/xtensa/include/asm/page.h
+++ b/arch/xtensa/include/asm/page.h
@@ -33,8 +33,14 @@
#define PAGE_SIZE (__XTENSA_UL_CONST(1) << PAGE_SHIFT)
#define PAGE_MASK (~(PAGE_SIZE-1))
+#ifdef CONFIG_MMU
#define PAGE_OFFSET XCHAL_KSEG_CACHED_VADDR
#define MAX_MEM_PFN XCHAL_KSEG_SIZE
+#else
+#define PAGE_OFFSET 0
+#define MAX_MEM_PFN (PLATFORM_DEFAULT_MEM_START + PLATFORM_DEFAULT_MEM_SIZE)
+#endif
+
#define PGTABLE_START 0x80000000
/*
@@ -165,8 +171,9 @@
#define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
#define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT)
+#ifdef CONFIG_MMU
#define WANT_PAGE_VIRTUAL
-
+#endif
#endif /* __ASSEMBLY__ */
diff --git a/arch/xtensa/include/asm/pgtable.h b/arch/xtensa/include/asm/pgtable.h
index 8014d96..a138770 100644
--- a/arch/xtensa/include/asm/pgtable.h
+++ b/arch/xtensa/include/asm/pgtable.h
@@ -183,7 +183,15 @@
#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
+#ifdef CONFIG_MMU
extern pgd_t swapper_pg_dir[PAGE_SIZE/sizeof(pgd_t)];
+extern void paging_init(void);
+extern void pgtable_cache_init(void);
+#else
+# define swapper_pg_dir NULL
+static inline void paging_init(void) { }
+static inline void pgtable_cache_init(void) { }
+#endif
/*
* The pmd contains the kernel virtual address of the pte page.
@@ -383,8 +391,6 @@
#else
-extern void paging_init(void);
-
#define kern_addr_valid(addr) (1)
extern void update_mmu_cache(struct vm_area_struct * vma,
@@ -398,9 +404,6 @@
#define io_remap_pfn_range(vma,from,pfn,size,prot) \
remap_pfn_range(vma, from, pfn, size, prot)
-
-extern void pgtable_cache_init(void);
-
typedef pte_t *pte_addr_t;
#endif /* !defined (__ASSEMBLY__) */
diff --git a/arch/xtensa/include/asm/processor.h b/arch/xtensa/include/asm/processor.h
index fba8b7e..0ea4937 100644
--- a/arch/xtensa/include/asm/processor.h
+++ b/arch/xtensa/include/asm/processor.h
@@ -13,6 +13,7 @@
#include <variant/core.h>
#include <asm/coprocessor.h>
+#include <platform/hardware.h>
#include <linux/compiler.h>
#include <asm/ptrace.h>
@@ -35,7 +36,12 @@
* the 1 GB requirement applies to the stack as well.
*/
+#ifdef CONFIG_MMU
#define TASK_SIZE __XTENSA_UL_CONST(0x40000000)
+#else
+#define TASK_SIZE (PLATFORM_DEFAULT_MEM_START + PLATFORM_DEFAULT_MEM_SIZE)
+#endif
+
#define STACK_TOP TASK_SIZE
#define STACK_TOP_MAX STACK_TOP