powerpc: Convert flush_icache_range & friends to C

Similar to commit 22e9c88d486a
("powerpc/64: reuse PPC32 static inline flush_dcache_range()")
this patch converts the following ASM symbols to C:
    flush_icache_range()
    __flush_dcache_icache()
    __flush_dcache_icache_phys()

This was done as we discovered a long-standing bug where the length of the
range was truncated due to using a 32 bit shift instead of a 64 bit one.

By converting these functions to C, it becomes easier to maintain.

flush_dcache_icache_phys() retains a critical assembler section as we must
ensure there are no memory accesses while the data MMU is disabled
(authored by Christophe Leroy). Since this has no external callers, it has
also been made static, allowing the compiler to inline it within
flush_dcache_icache_page().

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
[mpe: Minor fixups, don't export __flush_dcache_icache()]
Link: https://lore.kernel.org/r/20191104023305.9581-5-alastair@au1.ibm.com

1 files changed, 0 insertions, 120 deletions

diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index 82df4b09e79f..f4e4a1926a7a 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -317,126 +317,6 @@ EXPORT_SYMBOL(flush_instruction_cache)
 #endif /* CONFIG_PPC_8xx */
 
 /*
- * Write any modified data cache blocks out to memory
- * and invalidate the corresponding instruction cache blocks.
- * This is a no-op on the 601.
- *
- * flush_icache_range(unsigned long start, unsigned long stop)
- */
-_GLOBAL(flush_icache_range)
-#if defined(CONFIG_PPC_BOOK3S_601) || defined(CONFIG_E200)
-	PURGE_PREFETCHED_INS
-	blr				/* for 601 and e200, do nothing */
-#else
-	rlwinm	r3,r3,0,0,31 - L1_CACHE_SHIFT
-	subf	r4,r3,r4
-	addi	r4,r4,L1_CACHE_BYTES - 1
-	srwi.	r4,r4,L1_CACHE_SHIFT
-	beqlr
-	mtctr	r4
-	mr	r6,r3
-1:	dcbst	0,r3
-	addi	r3,r3,L1_CACHE_BYTES
-	bdnz	1b
-	sync				/* wait for dcbst's to get to ram */
-#ifndef CONFIG_44x
-	mtctr	r4
-2:	icbi	0,r6
-	addi	r6,r6,L1_CACHE_BYTES
-	bdnz	2b
-#else
-	/* Flash invalidate on 44x because we are passed kmapped addresses and
-	   this doesn't work for userspace pages due to the virtually tagged
-	   icache.  Sigh. */
-	iccci	0, r0
-#endif
-	sync				/* additional sync needed on g4 */
-	isync
-	blr
-#endif
-_ASM_NOKPROBE_SYMBOL(flush_icache_range)
-EXPORT_SYMBOL(flush_icache_range)
-
-/*
- * Flush a particular page from the data cache to RAM.
- * Note: this is necessary because the instruction cache does *not*
- * snoop from the data cache.
- * This is a no-op on the 601 and e200 which have a unified cache.
- *
- *	void __flush_dcache_icache(void *page)
- */
-_GLOBAL(__flush_dcache_icache)
-#if defined(CONFIG_PPC_BOOK3S_601) || defined(CONFIG_E200)
-	PURGE_PREFETCHED_INS
-	blr
-#else
-	rlwinm	r3,r3,0,0,31-PAGE_SHIFT		/* Get page base address */
-	li	r4,PAGE_SIZE/L1_CACHE_BYTES	/* Number of lines in a page */
-	mtctr	r4
-	mr	r6,r3
-0:	dcbst	0,r3				/* Write line to ram */
-	addi	r3,r3,L1_CACHE_BYTES
-	bdnz	0b
-	sync
-#ifdef CONFIG_44x
-	/* We don't flush the icache on 44x. Those have a virtual icache
-	 * and we don't have access to the virtual address here (it's
-	 * not the page vaddr but where it's mapped in user space). The
-	 * flushing of the icache on these is handled elsewhere, when
-	 * a change in the address space occurs, before returning to
-	 * user space
-	 */
-BEGIN_MMU_FTR_SECTION
-	blr
-END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_44x)
-#endif /* CONFIG_44x */
-	mtctr	r4
-1:	icbi	0,r6
-	addi	r6,r6,L1_CACHE_BYTES
-	bdnz	1b
-	sync
-	isync
-	blr
-#endif
-
-#ifndef CONFIG_BOOKE
-/*
- * Flush a particular page from the data cache to RAM, identified
- * by its physical address.  We turn off the MMU so we can just use
- * the physical address (this may be a highmem page without a kernel
- * mapping).
- *
- *	void __flush_dcache_icache_phys(unsigned long physaddr)
- */
-_GLOBAL(__flush_dcache_icache_phys)
-#if defined(CONFIG_PPC_BOOK3S_601) || defined(CONFIG_E200)
-	PURGE_PREFETCHED_INS
-	blr					/* for 601 and e200, do nothing */
-#else
-	mfmsr	r10
-	rlwinm	r0,r10,0,28,26			/* clear DR */
-	mtmsr	r0
-	isync
-	rlwinm	r3,r3,0,0,31-PAGE_SHIFT		/* Get page base address */
-	li	r4,PAGE_SIZE/L1_CACHE_BYTES	/* Number of lines in a page */
-	mtctr	r4
-	mr	r6,r3
-0:	dcbst	0,r3				/* Write line to ram */
-	addi	r3,r3,L1_CACHE_BYTES
-	bdnz	0b
-	sync
-	mtctr	r4
-1:	icbi	0,r6
-	addi	r6,r6,L1_CACHE_BYTES
-	bdnz	1b
-	sync
-	mtmsr	r10				/* restore DR */
-	isync
-	blr
-#endif
-#endif /* CONFIG_BOOKE */
-
-/*
  * Copy a whole page.  We use the dcbz instruction on the destination
  * to reduce memory traffic (it eliminates the unnecessary reads of
  * the destination into cache).  This requires that the destination