[PATCH v2 03/14] powerpc: make ioremap_bot common to PPC32 and PPC64

From: Christophe Leroy
Date: Wed May 16 2018 - 05:37:39 EST


Today, early ioremap maps from IOREMAP_BASE down to up on PPC64
and from IOREMAP_TOP up to down on PPC32

This patchs modifies PPC32 behaviour to get same behaviour as PPC64

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/include/asm/book3s/32/pgtable.h | 29 ++++++++++++++++++------
arch/powerpc/include/asm/highmem.h | 11 ----------
arch/powerpc/include/asm/nohash/32/pgtable.h | 33 ++++++++++++++++++----------
arch/powerpc/mm/dma-noncoherent.c | 2 +-
arch/powerpc/mm/dump_linuxpagetables.c | 6 ++---
arch/powerpc/mm/init_32.c | 6 ++++-
arch/powerpc/mm/ioremap.c | 21 +++++++++---------
arch/powerpc/mm/mem.c | 7 +++---
8 files changed, 66 insertions(+), 49 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h
index c615abdce119..ccf0d77277b1 100644
--- a/arch/powerpc/include/asm/book3s/32/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/32/pgtable.h
@@ -50,20 +50,32 @@
* virtual space that goes below PKMAP and FIXMAP
*/
#ifdef CONFIG_HIGHMEM
+#ifdef CONFIG_PPC_4K_PAGES
+#define PKMAP_ORDER PTE_SHIFT
+#else
+#define PKMAP_ORDER 9
+#endif
+#define LAST_PKMAP (1 << PKMAP_ORDER)
+#ifndef CONFIG_PPC_4K_PAGES
+#define PKMAP_BASE (FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1))
+#else
+#define PKMAP_BASE ((FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1)) & PMD_MASK)
+#endif
#define KVIRT_TOP PKMAP_BASE
#else
#define KVIRT_TOP (0xfe000000UL) /* for now, could be FIXMAP_BASE ? */
#endif
+#define IOREMAP_BASE VMALLOC_BASE

/*
- * ioremap_bot starts at that address. Early ioremaps move down from there,
- * until mem_init() at which point this becomes the top of the vmalloc
+ * ioremap_bot starts at IOREMAP_BASE. Early ioremaps move up from there,
+ * until mem_init() at which point this becomes the bottom of the vmalloc
* and ioremap space
*/
#ifdef CONFIG_NOT_COHERENT_CACHE
-#define IOREMAP_TOP ((KVIRT_TOP - CONFIG_CONSISTENT_SIZE) & PAGE_MASK)
+#define IOREMAP_END ((KVIRT_TOP - CONFIG_CONSISTENT_SIZE) & PAGE_MASK)
#else
-#define IOREMAP_TOP KVIRT_TOP
+#define IOREMAP_END KVIRT_TOP
#endif

/*
@@ -85,11 +97,12 @@
*/
#define VMALLOC_OFFSET (0x1000000) /* 16M */
#ifdef PPC_PIN_SIZE
-#define VMALLOC_START (((_ALIGN((long)high_memory, PPC_PIN_SIZE) + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
+#define VMALLOC_BASE (((_ALIGN((long)high_memory, PPC_PIN_SIZE) + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
#else
-#define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
+#define VMALLOC_BASE ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
#endif
-#define VMALLOC_END ioremap_bot
+#define VMALLOC_START ioremap_bot
+#define VMALLOC_END IOREMAP_END

#ifndef __ASSEMBLY__
#include <linux/sched.h>
@@ -298,6 +311,8 @@ static inline void __ptep_set_access_flags(struct mm_struct *mm,

int map_kernel_page(unsigned long va, phys_addr_t pa, int flags);

+#include <asm/fixmap.h>
+
/* Generic accessors to PTE bits */
static inline int pte_write(pte_t pte) { return !!(pte_val(pte) & _PAGE_RW);}
static inline int pte_read(pte_t pte) { return 1; }
diff --git a/arch/powerpc/include/asm/highmem.h b/arch/powerpc/include/asm/highmem.h
index cec820f961da..2eacea504da2 100644
--- a/arch/powerpc/include/asm/highmem.h
+++ b/arch/powerpc/include/asm/highmem.h
@@ -44,17 +44,6 @@ extern pte_t *pkmap_page_table;
* and PKMAP can be placed in a single pte table. We use 512 pages for PKMAP
* in case of 16K/64K/256K page sizes.
*/
-#ifdef CONFIG_PPC_4K_PAGES
-#define PKMAP_ORDER PTE_SHIFT
-#else
-#define PKMAP_ORDER 9
-#endif
-#define LAST_PKMAP (1 << PKMAP_ORDER)
-#ifndef CONFIG_PPC_4K_PAGES
-#define PKMAP_BASE (FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1))
-#else
-#define PKMAP_BASE ((FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1)) & PMD_MASK)
-#endif
#define LAST_PKMAP_MASK (LAST_PKMAP-1)
#define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT)
#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h
index 987a658b18e1..db4e530dd5f3 100644
--- a/arch/powerpc/include/asm/nohash/32/pgtable.h
+++ b/arch/powerpc/include/asm/nohash/32/pgtable.h
@@ -69,6 +69,17 @@ extern int icache_44x_need_flush;
* virtual space that goes below PKMAP and FIXMAP
*/
#ifdef CONFIG_HIGHMEM
+#ifdef CONFIG_PPC_4K_PAGES
+#define PKMAP_ORDER PTE_SHIFT
+#else
+#define PKMAP_ORDER 9
+#endif
+#define LAST_PKMAP (1 << PKMAP_ORDER)
+#ifndef CONFIG_PPC_4K_PAGES
+#define PKMAP_BASE (FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1))
+#else
+#define PKMAP_BASE ((FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1)) & PMD_MASK)
+#endif
#define KVIRT_TOP PKMAP_BASE
#else
#define KVIRT_TOP (0xfe000000UL) /* for now, could be FIXMAP_BASE ? */
@@ -80,10 +91,11 @@ extern int icache_44x_need_flush;
* and ioremap space
*/
#ifdef CONFIG_NOT_COHERENT_CACHE
-#define IOREMAP_TOP ((KVIRT_TOP - CONFIG_CONSISTENT_SIZE) & PAGE_MASK)
+#define IOREMAP_END ((KVIRT_TOP - CONFIG_CONSISTENT_SIZE) & PAGE_MASK)
#else
-#define IOREMAP_TOP KVIRT_TOP
+#define IOREMAP_END KVIRT_TOP
#endif
+#define IOREMAP_BASE VMALLOC_BASE

/*
* Just any arbitrary offset to the start of the vmalloc VM area: the
@@ -94,21 +106,16 @@ extern int icache_44x_need_flush;
* area for the same reason. ;)
*
* We no longer map larger than phys RAM with the BATs so we don't have
- * to worry about the VMALLOC_OFFSET causing problems. We do have to worry
- * about clashes between our early calls to ioremap() that start growing down
- * from IOREMAP_TOP being run into the VM area allocations (growing upwards
- * from VMALLOC_START). For this reason we have ioremap_bot to check when
- * we actually run into our mappings setup in the early boot with the VM
- * system. This really does become a problem for machines with good amounts
- * of RAM. -- Cort
+ * to worry about the VMALLOC_OFFSET causing problems.
*/
#define VMALLOC_OFFSET (0x1000000) /* 16M */
#ifdef PPC_PIN_SIZE
-#define VMALLOC_START (((_ALIGN((long)high_memory, PPC_PIN_SIZE) + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
+#define VMALLOC_BASE (((_ALIGN((long)high_memory, PPC_PIN_SIZE) + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
#else
-#define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
+#define VMALLOC_BASE ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
#endif
-#define VMALLOC_END ioremap_bot
+#define VMALLOC_START ioremap_bot
+#define VMALLOC_END IOREMAP_END

/*
* Bits in a linux-style PTE. These match the bits in the
@@ -325,6 +332,8 @@ static inline int pte_young(pte_t pte)

int map_kernel_page(unsigned long va, phys_addr_t pa, int flags);

+#include <asm/fixmap.h>
+
#endif /* !__ASSEMBLY__ */

#endif /* __ASM_POWERPC_NOHASH_32_PGTABLE_H */
diff --git a/arch/powerpc/mm/dma-noncoherent.c b/arch/powerpc/mm/dma-noncoherent.c
index 382528475433..d0a8fe74f5a0 100644
--- a/arch/powerpc/mm/dma-noncoherent.c
+++ b/arch/powerpc/mm/dma-noncoherent.c
@@ -43,7 +43,7 @@
* can be further configured for specific applications under
* the "Advanced Setup" menu. -Matt
*/
-#define CONSISTENT_BASE (IOREMAP_TOP)
+#define CONSISTENT_BASE (IOREMAP_END)
#define CONSISTENT_END (CONSISTENT_BASE + CONFIG_CONSISTENT_SIZE)
#define CONSISTENT_OFFSET(x) (((unsigned long)(x) - CONSISTENT_BASE) >> PAGE_SHIFT)

diff --git a/arch/powerpc/mm/dump_linuxpagetables.c b/arch/powerpc/mm/dump_linuxpagetables.c
index 876e2a3c79f2..6022adb899b7 100644
--- a/arch/powerpc/mm/dump_linuxpagetables.c
+++ b/arch/powerpc/mm/dump_linuxpagetables.c
@@ -452,11 +452,11 @@ static void populate_markers(void)
address_markers[i++].start_address = VMEMMAP_BASE;
#endif
#else /* !CONFIG_PPC64 */
+ address_markers[i++].start_address = IOREMAP_BASE;
address_markers[i++].start_address = ioremap_bot;
- address_markers[i++].start_address = IOREMAP_TOP;
#ifdef CONFIG_NOT_COHERENT_CACHE
- address_markers[i++].start_address = IOREMAP_TOP;
- address_markers[i++].start_address = IOREMAP_TOP +
+ address_markers[i++].start_address = IOREMAP_END;
+ address_markers[i++].start_address = IOREMAP_END +
CONFIG_CONSISTENT_SIZE;
#endif
#ifdef CONFIG_HIGHMEM
diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c
index 3e59e5d64b01..7fb9e5a9852a 100644
--- a/arch/powerpc/mm/init_32.c
+++ b/arch/powerpc/mm/init_32.c
@@ -172,7 +172,11 @@ void __init MMU_init(void)
mapin_ram();

/* Initialize early top-down ioremap allocator */
- ioremap_bot = IOREMAP_TOP;
+ if (IS_ENABLED(CONFIG_HIGHMEM))
+ high_memory = (void *) __va(lowmem_end_addr);
+ else
+ high_memory = (void *) __va(memblock_end_of_DRAM());
+ ioremap_bot = IOREMAP_BASE;

if (ppc_md.progress)
ppc_md.progress("MMU:exit", 0x211);
diff --git a/arch/powerpc/mm/ioremap.c b/arch/powerpc/mm/ioremap.c
index 0c8f6113e0f3..a498e3cade9e 100644
--- a/arch/powerpc/mm/ioremap.c
+++ b/arch/powerpc/mm/ioremap.c
@@ -28,11 +28,15 @@

#include "mmu_decl.h"

-#ifdef CONFIG_PPC32
-
+#if defined(CONFIG_PPC_BOOK3S_64) || defined(CONFIG_PPC32)
unsigned long ioremap_bot;
+#else
+unsigned long ioremap_bot = IOREMAP_BASE;
+#endif
EXPORT_SYMBOL(ioremap_bot); /* aka VMALLOC_END */

+#ifdef CONFIG_PPC32
+
void __iomem *
ioremap(phys_addr_t addr, unsigned long size)
{
@@ -90,7 +94,7 @@ __ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
/*
* Choose an address to map it to.
* Once the vmalloc system is running, we use it.
- * Before then, we use space going down from IOREMAP_TOP
+ * Before then, we use space going up from IOREMAP_BASE
* (ioremap_bot records where we're up to).
*/
p = addr & PAGE_MASK;
@@ -135,7 +139,8 @@ __ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
area->phys_addr = p;
v = (unsigned long) area->addr;
} else {
- v = (ioremap_bot -= size);
+ v = ioremap_bot;
+ ioremap_bot += size;
}

/*
@@ -164,19 +169,13 @@ void iounmap(volatile void __iomem *addr)
if (v_block_mapped((unsigned long)addr))
return;

- if (addr > high_memory && (unsigned long) addr < ioremap_bot)
+ if ((unsigned long) addr >= ioremap_bot)
vunmap((void *) (PAGE_MASK & (unsigned long)addr));
}
EXPORT_SYMBOL(iounmap);

#else

-#ifdef CONFIG_PPC_BOOK3S_64
-unsigned long ioremap_bot;
-#else /* !CONFIG_PPC_BOOK3S_64 */
-unsigned long ioremap_bot = IOREMAP_BASE;
-#endif
-
/**
* __ioremap_at - Low level function to establish the page tables
* for an IO mapping
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index c3c39b02b2ba..b680aa78a4ac 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -345,8 +345,9 @@ void __init mem_init(void)
#ifdef CONFIG_SWIOTLB
swiotlb_init(0);
#endif
-
+#ifdef CONFIG_PPC64
high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
+#endif
set_max_mapnr(max_pfn);
free_all_bootmem();

@@ -383,10 +384,10 @@ void __init mem_init(void)
#endif /* CONFIG_HIGHMEM */
#ifdef CONFIG_NOT_COHERENT_CACHE
pr_info(" * 0x%08lx..0x%08lx : consistent mem\n",
- IOREMAP_TOP, IOREMAP_TOP + CONFIG_CONSISTENT_SIZE);
+ IOREMAP_END, IOREMAP_END + CONFIG_CONSISTENT_SIZE);
#endif /* CONFIG_NOT_COHERENT_CACHE */
pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
- ioremap_bot, IOREMAP_TOP);
+ IOREMAP_BASE, ioremap_bot);
pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
VMALLOC_START, VMALLOC_END);
#endif /* CONFIG_PPC32 */
--
2.13.3