Merge branch 'for-rmk/arm-mm-lpae' of git://git.kernel.org/pub/scm/linux/kernel/git/ssantosh/linux-keystone into devel-stable

This series extends the existing ARM v2p runtime patching for 64 bit.
Needed for LPAE machines which have physical memory beyond 4GB.

8 files changed, 206 insertions, 30 deletions

diff --git a/arch/arm/include/asm/mach/arch.h b/arch/arm/include/asm/mach/arch.h
index 402a2bc6aa68..17a3fa2979e8 100644
--- a/arch/arm/include/asm/mach/arch.h
+++ b/arch/arm/include/asm/mach/arch.h
@@ -49,6 +49,7 @@ struct machine_desc {
 	bool			(*smp_init)(void);
 	void			(*fixup)(struct tag *, char **,
 					 struct meminfo *);
+	void			(*init_meminfo)(void);
 	void			(*reserve)(void);/* reserve mem blocks	*/
 	void			(*map_io)(void);/* IO mapping function	*/
 	void			(*init_early)(void);
diff --git a/arch/arm/include/asm/memory.h b/arch/arm/include/asm/memory.h
index e750a938fd3c..6748d6295a1a 100644
--- a/arch/arm/include/asm/memory.h
+++ b/arch/arm/include/asm/memory.h
@@ -172,8 +172,14 @@
  * so that all we need to do is modify the 8-bit constant field.
  */
 #define __PV_BITS_31_24	0x81000000
+#define __PV_BITS_7_0	0x81
+
+extern phys_addr_t (*arch_virt_to_idmap) (unsigned long x);
+extern u64 __pv_phys_offset;
+extern u64 __pv_offset;
+extern void fixup_pv_table(const void *, unsigned long);
+extern const void *__pv_table_begin, *__pv_table_end;
 
-extern unsigned long __pv_phys_offset;
 #define PHYS_OFFSET __pv_phys_offset
 
 #define __pv_stub(from,to,instr,type)			\
@@ -185,22 +191,58 @@ extern unsigned long __pv_phys_offset;
 	: "=r" (to)					\
 	: "r" (from), "I" (type))
 
-static inline unsigned long __virt_to_phys(unsigned long x)
+#define __pv_stub_mov_hi(t)				\
+	__asm__ volatile("@ __pv_stub_mov\n"		\
+	"1:	mov	%R0, %1\n"			\
+	"	.pushsection .pv_table,\"a\"\n"		\
+	"	.long	1b\n"				\
+	"	.popsection\n"				\
+	: "=r" (t)					\
+	: "I" (__PV_BITS_7_0))
+
+#define __pv_add_carry_stub(x, y)			\
+	__asm__ volatile("@ __pv_add_carry_stub\n"	\
+	"1:	adds	%Q0, %1, %2\n"			\
+	"	adc	%R0, %R0, #0\n"			\
+	"	.pushsection .pv_table,\"a\"\n"		\
+	"	.long	1b\n"				\
+	"	.popsection\n"				\
+	: "+r" (y)					\
+	: "r" (x), "I" (__PV_BITS_31_24)		\
+	: "cc")
+
+static inline phys_addr_t __virt_to_phys(unsigned long x)
 {
-	unsigned long t;
-	__pv_stub(x, t, "add", __PV_BITS_31_24);
+	phys_addr_t t;
+
+	if (sizeof(phys_addr_t) == 4) {
+		__pv_stub(x, t, "add", __PV_BITS_31_24);
+	} else {
+		__pv_stub_mov_hi(t);
+		__pv_add_carry_stub(x, t);
+	}
 	return t;
 }
 
-static inline unsigned long __phys_to_virt(unsigned long x)
+static inline unsigned long __phys_to_virt(phys_addr_t x)
 {
 	unsigned long t;
 	__pv_stub(x, t, "sub", __PV_BITS_31_24);
 	return t;
 }
+
 #else
-#define __virt_to_phys(x)	((x) - PAGE_OFFSET + PHYS_OFFSET)
-#define __phys_to_virt(x)	((x) - PHYS_OFFSET + PAGE_OFFSET)
+
+static inline phys_addr_t __virt_to_phys(unsigned long x)
+{
+	return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
+}
+
+static inline unsigned long __phys_to_virt(phys_addr_t x)
+{
+	return x - PHYS_OFFSET + PAGE_OFFSET;
+}
+
 #endif
 #endif
 #endif /* __ASSEMBLY__ */
@@ -238,17 +280,32 @@ static inline phys_addr_t virt_to_phys(const volatile void *x)
 
 static inline void *phys_to_virt(phys_addr_t x)
 {
-	return (void *)(__phys_to_virt((unsigned long)(x)));
+	return (void *)__phys_to_virt(x);
 }
 
 /*
  * Drivers should NOT use these either.
  */
 #define __pa(x)			__virt_to_phys((unsigned long)(x))
-#define __va(x)			((void *)__phys_to_virt((unsigned long)(x)))
+#define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
 
 /*
+ * These are for systems that have a hardware interconnect supported alias of
+ * physical memory for idmap purposes.  Most cases should leave these
+ * untouched.
+ */
+static inline phys_addr_t __virt_to_idmap(unsigned long x)
+{
+	if (arch_virt_to_idmap)
+		return arch_virt_to_idmap(x);
+	else
+		return __virt_to_phys(x);
+}
+
+#define virt_to_idmap(x)	__virt_to_idmap((unsigned long)(x))
+
+/*
  * Virtual <-> DMA view memory address translations
  * Again, these are *only* valid on the kernel direct mapped RAM
  * memory.  Use of these is *deprecated* (and that doesn't mean
diff --git a/arch/arm/kernel/armksyms.c b/arch/arm/kernel/armksyms.c
index 60d3b738d420..1f031ddd0667 100644
--- a/arch/arm/kernel/armksyms.c
+++ b/arch/arm/kernel/armksyms.c
@@ -155,4 +155,5 @@ EXPORT_SYMBOL(__gnu_mcount_nc);
 
 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT
 EXPORT_SYMBOL(__pv_phys_offset);
+EXPORT_SYMBOL(__pv_offset);
 #endif
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 2c7cc1e03473..54547947a4e9 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -536,6 +536,14 @@ ENTRY(fixup_smp)
 	ldmfd	sp!, {r4 - r6, pc}
 ENDPROC(fixup_smp)
 
+#ifdef __ARMEB_
+#define LOW_OFFSET	0x4
+#define HIGH_OFFSET	0x0
+#else
+#define LOW_OFFSET	0x0
+#define HIGH_OFFSET	0x4
+#endif
+
 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT
 
 /* __fixup_pv_table - patch the stub instructions with the delta between
@@ -546,17 +554,20 @@ ENDPROC(fixup_smp)
 	__HEAD
 __fixup_pv_table:
 	adr	r0, 1f
-	ldmia	r0, {r3-r5, r7}
-	sub	r3, r0, r3	@ PHYS_OFFSET - PAGE_OFFSET
+	ldmia	r0, {r3-r7}
+	mvn	ip, #0
+	subs	r3, r0, r3	@ PHYS_OFFSET - PAGE_OFFSET
 	add	r4, r4, r3	@ adjust table start address
 	add	r5, r5, r3	@ adjust table end address
-	add	r7, r7, r3	@ adjust __pv_phys_offset address
-	str	r8, [r7]	@ save computed PHYS_OFFSET to __pv_phys_offset
+	add	r6, r6, r3	@ adjust __pv_phys_offset address
+	add	r7, r7, r3	@ adjust __pv_offset address
+	str	r8, [r6, #LOW_OFFSET]	@ save computed PHYS_OFFSET to __pv_phys_offset
+	strcc	ip, [r7, #HIGH_OFFSET]	@ save to __pv_offset high bits
 	mov	r6, r3, lsr #24	@ constant for add/sub instructions
 	teq	r3, r6, lsl #24 @ must be 16MiB aligned
 THUMB(	it	ne		@ cross section branch )
 	bne	__error
-	str	r6, [r7, #4]	@ save to __pv_offset
+	str	r3, [r7, #LOW_OFFSET]	@ save to __pv_offset low bits
 	b	__fixup_a_pv_table
 ENDPROC(__fixup_pv_table)
 
@@ -565,10 +576,19 @@ ENDPROC(__fixup_pv_table)
 	.long	__pv_table_begin
 	.long	__pv_table_end
 2:	.long	__pv_phys_offset
+	.long	__pv_offset
 
 	.text
 __fixup_a_pv_table:
+	adr	r0, 3f
+	ldr	r6, [r0]
+	add	r6, r6, r3
+	ldr	r0, [r6, #HIGH_OFFSET]	@ pv_offset high word
+	ldr	r6, [r6, #LOW_OFFSET]	@ pv_offset low word
+	mov	r6, r6, lsr #24
+	cmn	r0, #1
 #ifdef CONFIG_THUMB2_KERNEL
+	moveq	r0, #0x200000	@ set bit 21, mov to mvn instruction
 	lsls	r6, #24
 	beq	2f
 	clz	r7, r6
@@ -582,18 +602,28 @@ __fixup_a_pv_table:
 	b	2f
 1:	add     r7, r3
 	ldrh	ip, [r7, #2]
-	and	ip, 0x8f00
-	orr	ip, r6	@ mask in offset bits 31-24
+	tst	ip, #0x4000
+	and	ip, #0x8f00
+	orrne	ip, r6	@ mask in offset bits 31-24
+	orreq	ip, r0	@ mask in offset bits 7-0
 	strh	ip, [r7, #2]
+	ldrheq	ip, [r7]
+	biceq	ip, #0x20
+	orreq	ip, ip, r0, lsr #16
+	strheq	ip, [r7]
 2:	cmp	r4, r5
 	ldrcc	r7, [r4], #4	@ use branch for delay slot
 	bcc	1b
 	bx	lr
 #else
+	moveq	r0, #0x400000	@ set bit 22, mov to mvn instruction
 	b	2f
 1:	ldr	ip, [r7, r3]
 	bic	ip, ip, #0x000000ff
-	orr	ip, ip, r6	@ mask in offset bits 31-24
+	tst	ip, #0xf00	@ check the rotation field
+	orrne	ip, ip, r6	@ mask in offset bits 31-24
+	biceq	ip, ip, #0x400000	@ clear bit 22
+	orreq	ip, ip, r0	@ mask in offset bits 7-0
 	str	ip, [r7, r3]
 2:	cmp	r4, r5
 	ldrcc	r7, [r4], #4	@ use branch for delay slot
@@ -602,28 +632,29 @@ __fixup_a_pv_table:
 #endif
 ENDPROC(__fixup_a_pv_table)
 
+3:	.long __pv_offset
+
 ENTRY(fixup_pv_table)
 	stmfd	sp!, {r4 - r7, lr}
-	ldr	r2, 2f			@ get address of __pv_phys_offset
 	mov	r3, #0			@ no offset
 	mov	r4, r0			@ r0 = table start
 	add	r5, r0, r1		@ r1 = table size
-	ldr	r6, [r2, #4]		@ get __pv_offset
 	bl	__fixup_a_pv_table
 	ldmfd	sp!, {r4 - r7, pc}
 ENDPROC(fixup_pv_table)
 
-	.align
-2:	.long	__pv_phys_offset
-
 	.data
 	.globl	__pv_phys_offset
 	.type	__pv_phys_offset, %object
 __pv_phys_offset:
-	.long	0
-	.size	__pv_phys_offset, . - __pv_phys_offset
+	.quad	0
+	.size	__pv_phys_offset, . -__pv_phys_offset
+
+	.globl	__pv_offset
+	.type	__pv_offset, %object
 __pv_offset:
-	.long	0
+	.quad	0
+	.size	__pv_offset, . -__pv_offset
 #endif
 
 #include "head-common.S"
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 0e1e2b3afa45..af7b7db4699e 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -73,6 +73,8 @@ __setup("fpe=", fpe_setup);
 #endif
 
 extern void paging_init(const struct machine_desc *desc);
+extern void early_paging_init(const struct machine_desc *,
+			      struct proc_info_list *);
 extern void sanity_check_meminfo(void);
 extern enum reboot_mode reboot_mode;
 extern void setup_dma_zone(const struct machine_desc *desc);
@@ -878,6 +880,8 @@ void __init setup_arch(char **cmdline_p)
 	parse_early_param();
 
 	sort(&meminfo.bank, meminfo.nr_banks, sizeof(meminfo.bank[0]), meminfo_cmp, NULL);
+
+	early_paging_init(mdesc, lookup_processor_type(read_cpuid_id()));
 	sanity_check_meminfo();
 	arm_memblock_init(&meminfo, mdesc);
 
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 7d80a549cae5..5c820cbcf918 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -81,7 +81,7 @@ void __init smp_set_ops(struct smp_operations *ops)
 
 static unsigned long get_arch_pgd(pgd_t *pgd)
 {
-	phys_addr_t pgdir = virt_to_phys(pgd);
+	phys_addr_t pgdir = virt_to_idmap(pgd);
 	BUG_ON(pgdir & ARCH_PGD_MASK);
 	return pgdir >> ARCH_PGD_SHIFT;
 }
diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c
index 83cb3ac27095..8e0e52eb76b5 100644
--- a/arch/arm/mm/idmap.c
+++ b/arch/arm/mm/idmap.c
@@ -10,6 +10,7 @@
 #include <asm/system_info.h>
 
 pgd_t *idmap_pgd;
+phys_addr_t (*arch_virt_to_idmap) (unsigned long x);
 
 #ifdef CONFIG_ARM_LPAE
 static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end,
@@ -67,8 +68,9 @@ static void identity_mapping_add(pgd_t *pgd, const char *text_start,
 	unsigned long addr, end;
 	unsigned long next;
 
-	addr = virt_to_phys(text_start);
-	end = virt_to_phys(text_end);
+	addr = virt_to_idmap(text_start);
+	end = virt_to_idmap(text_end);
+	pr_info("Setting up static identity map for 0x%lx - 0x%lx\n", addr, end);
 
 	prot |= PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_SECT_AF;
 
@@ -90,8 +92,6 @@ static int __init init_static_idmap(void)
 	if (!idmap_pgd)
 		return -ENOMEM;
 
-	pr_info("Setting up static identity map for 0x%p - 0x%p\n",
-		__idmap_text_start, __idmap_text_end);
 	identity_mapping_add(idmap_pgd, __idmap_text_start,
 			     __idmap_text_end, 0);
 
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index b1d17eeb59b8..78eeeca78f5a 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -28,6 +28,8 @@
 #include <asm/highmem.h>
 #include <asm/system_info.h>
 #include <asm/traps.h>
+#include <asm/procinfo.h>
+#include <asm/memory.h>
 
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
@@ -1315,6 +1317,86 @@ static void __init map_lowmem(void)
 	}
 }
 
+#ifdef CONFIG_ARM_LPAE
+/*
+ * early_paging_init() recreates boot time page table setup, allowing machines
+ * to switch over to a high (>4G) address space on LPAE systems
+ */
+void __init early_paging_init(const struct machine_desc *mdesc,
+			      struct proc_info_list *procinfo)
+{
+	pmdval_t pmdprot = procinfo->__cpu_mm_mmu_flags;
+	unsigned long map_start, map_end;
+	pgd_t *pgd0, *pgdk;
+	pud_t *pud0, *pudk, *pud_start;
+	pmd_t *pmd0, *pmdk;
+	phys_addr_t phys;
+	int i;
+
+	if (!(mdesc->init_meminfo))
+		return;
+
+	/* remap kernel code and data */
+	map_start = init_mm.start_code;
+	map_end   = init_mm.brk;
+
+	/* get a handle on things... */
+	pgd0 = pgd_offset_k(0);
+	pud_start = pud0 = pud_offset(pgd0, 0);
+	pmd0 = pmd_offset(pud0, 0);
+
+	pgdk = pgd_offset_k(map_start);
+	pudk = pud_offset(pgdk, map_start);
+	pmdk = pmd_offset(pudk, map_start);
+
+	mdesc->init_meminfo();
+
+	/* Run the patch stub to update the constants */
+	fixup_pv_table(&__pv_table_begin,
+		(&__pv_table_end - &__pv_table_begin) << 2);
+
+	/*
+	 * Cache cleaning operations for self-modifying code
+	 * We should clean the entries by MVA but running a
+	 * for loop over every pv_table entry pointer would
+	 * just complicate the code.
+	 */
+	flush_cache_louis();
+	dsb();
+	isb();
+
+	/* remap level 1 table */
+	for (i = 0; i < PTRS_PER_PGD; pud0++, i++) {
+		set_pud(pud0,
+			__pud(__pa(pmd0) | PMD_TYPE_TABLE | L_PGD_SWAPPER));
+		pmd0 += PTRS_PER_PMD;
+	}
+
+	/* remap pmds for kernel mapping */
+	phys = __pa(map_start) & PMD_MASK;
+	do {
+		*pmdk++ = __pmd(phys | pmdprot);
+		phys += PMD_SIZE;
+	} while (phys < map_end);
+
+	flush_cache_all();
+	cpu_switch_mm(pgd0, &init_mm);
+	cpu_set_ttbr(1, __pa(pgd0) + TTBR1_OFFSET);
+	local_flush_bp_all();
+	local_flush_tlb_all();
+}
+
+#else
+
+void __init early_paging_init(const struct machine_desc *mdesc,
+			      struct proc_info_list *procinfo)
+{
+	if (mdesc->init_meminfo)
+		mdesc->init_meminfo();
+}
+
+#endif
+
 /*
  * paging_init() sets up the page tables, initialises the zone memory
  * maps, and sets up the zero page, bad page and bad page tables.