u-boot/arch/arm/cpu/armv8/cache.S
Philipp Tomsich e6a0586277 armv8: move low-level assembly functions into function-sections
TPL builds today don't need to call into firmware or set up the MMU
(if this changes, it should be controlled through a config option
whether to include this or not), but include the needed support code
for this anyway.  By moving these unused low-level functions into
seperate function-sections, the linker can garbage-collect the unused
sections.

Note that (if DM support is enabled), there will be a call to the
cache-flushing code from alloc_priv(...) in drivers/core/device.c.
This then add 52 bytes of binary size (an increase from 20589 to 20641
bytes) compared to completely removing this code.

Even for a feature-rich TPL (including DM support as for the RK3368),
this equates to a size difference of significantly more than 10% in
TPL binary size.

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2017-08-13 17:12:21 +02:00

268 lines
5.9 KiB
ArmAsm

/*
* (C) Copyright 2013
* David Feng <fenghua@phytium.com.cn>
*
* This file is based on sample code from ARMv8 ARM.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <asm-offsets.h>
#include <config.h>
#include <asm/macro.h>
#include <asm/system.h>
#include <linux/linkage.h>
/*
* void __asm_dcache_level(level)
*
* flush or invalidate one level cache.
*
* x0: cache level
* x1: 0 clean & invalidate, 1 invalidate only
* x2~x9: clobbered
*/
.pushsection .text.__asm_dcache_level, "ax"
ENTRY(__asm_dcache_level)
lsl x12, x0, #1
msr csselr_el1, x12 /* select cache level */
isb /* sync change of cssidr_el1 */
mrs x6, ccsidr_el1 /* read the new cssidr_el1 */
and x2, x6, #7 /* x2 <- log2(cache line size)-4 */
add x2, x2, #4 /* x2 <- log2(cache line size) */
mov x3, #0x3ff
and x3, x3, x6, lsr #3 /* x3 <- max number of #ways */
clz w5, w3 /* bit position of #ways */
mov x4, #0x7fff
and x4, x4, x6, lsr #13 /* x4 <- max number of #sets */
/* x12 <- cache level << 1 */
/* x2 <- line length offset */
/* x3 <- number of cache ways - 1 */
/* x4 <- number of cache sets - 1 */
/* x5 <- bit position of #ways */
loop_set:
mov x6, x3 /* x6 <- working copy of #ways */
loop_way:
lsl x7, x6, x5
orr x9, x12, x7 /* map way and level to cisw value */
lsl x7, x4, x2
orr x9, x9, x7 /* map set number to cisw value */
tbz w1, #0, 1f
dc isw, x9
b 2f
1: dc cisw, x9 /* clean & invalidate by set/way */
2: subs x6, x6, #1 /* decrement the way */
b.ge loop_way
subs x4, x4, #1 /* decrement the set */
b.ge loop_set
ret
ENDPROC(__asm_dcache_level)
.popsection
/*
* void __asm_flush_dcache_all(int invalidate_only)
*
* x0: 0 clean & invalidate, 1 invalidate only
*
* flush or invalidate all data cache by SET/WAY.
*/
.pushsection .text.__asm_dcache_all, "ax"
ENTRY(__asm_dcache_all)
mov x1, x0
dsb sy
mrs x10, clidr_el1 /* read clidr_el1 */
lsr x11, x10, #24
and x11, x11, #0x7 /* x11 <- loc */
cbz x11, finished /* if loc is 0, exit */
mov x15, lr
mov x0, #0 /* start flush at cache level 0 */
/* x0 <- cache level */
/* x10 <- clidr_el1 */
/* x11 <- loc */
/* x15 <- return address */
loop_level:
lsl x12, x0, #1
add x12, x12, x0 /* x0 <- tripled cache level */
lsr x12, x10, x12
and x12, x12, #7 /* x12 <- cache type */
cmp x12, #2
b.lt skip /* skip if no cache or icache */
bl __asm_dcache_level /* x1 = 0 flush, 1 invalidate */
skip:
add x0, x0, #1 /* increment cache level */
cmp x11, x0
b.gt loop_level
mov x0, #0
msr csselr_el1, x0 /* restore csselr_el1 */
dsb sy
isb
mov lr, x15
finished:
ret
ENDPROC(__asm_dcache_all)
.popsection
.pushsection .text.__asm_flush_dcache_all, "ax"
ENTRY(__asm_flush_dcache_all)
mov x0, #0
b __asm_dcache_all
ENDPROC(__asm_flush_dcache_all)
.popsection
.pushsection .text.__asm_invalidate_dcache_all, "ax"
ENTRY(__asm_invalidate_dcache_all)
mov x0, #0x1
b __asm_dcache_all
ENDPROC(__asm_invalidate_dcache_all)
.popsection
/*
* void __asm_flush_dcache_range(start, end)
*
* clean & invalidate data cache in the range
*
* x0: start address
* x1: end address
*/
.pushsection .text.__asm_flush_dcache_range, "ax"
ENTRY(__asm_flush_dcache_range)
mrs x3, ctr_el0
lsr x3, x3, #16
and x3, x3, #0xf
mov x2, #4
lsl x2, x2, x3 /* cache line size */
/* x2 <- minimal cache line size in cache system */
sub x3, x2, #1
bic x0, x0, x3
1: dc civac, x0 /* clean & invalidate data or unified cache */
add x0, x0, x2
cmp x0, x1
b.lo 1b
dsb sy
ret
ENDPROC(__asm_flush_dcache_range)
.popsection
/*
* void __asm_invalidate_dcache_range(start, end)
*
* invalidate data cache in the range
*
* x0: start address
* x1: end address
*/
.pushsection .text.__asm_invalidate_dcache_range, "ax"
ENTRY(__asm_invalidate_dcache_range)
mrs x3, ctr_el0
ubfm x3, x3, #16, #19
mov x2, #4
lsl x2, x2, x3 /* cache line size */
/* x2 <- minimal cache line size in cache system */
sub x3, x2, #1
bic x0, x0, x3
1: dc ivac, x0 /* invalidate data or unified cache */
add x0, x0, x2
cmp x0, x1
b.lo 1b
dsb sy
ret
ENDPROC(__asm_invalidate_dcache_range)
.popsection
/*
* void __asm_invalidate_icache_all(void)
*
* invalidate all tlb entries.
*/
.pushsection .text.__asm_invalidate_icache_all, "ax"
ENTRY(__asm_invalidate_icache_all)
ic ialluis
isb sy
ret
ENDPROC(__asm_invalidate_icache_all)
.popsection
.pushsection .text.__asm_invalidate_l3_dcache, "ax"
ENTRY(__asm_invalidate_l3_dcache)
mov x0, #0 /* return status as success */
ret
ENDPROC(__asm_invalidate_l3_dcache)
.weak __asm_invalidate_l3_dcache
.popsection
.pushsection .text.__asm_flush_l3_dcache, "ax"
ENTRY(__asm_flush_l3_dcache)
mov x0, #0 /* return status as success */
ret
ENDPROC(__asm_flush_l3_dcache)
.weak __asm_flush_l3_dcache
.popsection
.pushsection .text.__asm_invalidate_l3_icache, "ax"
ENTRY(__asm_invalidate_l3_icache)
mov x0, #0 /* return status as success */
ret
ENDPROC(__asm_invalidate_l3_icache)
.weak __asm_invalidate_l3_icache
.popsection
/*
* void __asm_switch_ttbr(ulong new_ttbr)
*
* Safely switches to a new page table.
*/
.pushsection .text.__asm_switch_ttbr, "ax"
ENTRY(__asm_switch_ttbr)
/* x2 = SCTLR (alive throghout the function) */
switch_el x4, 3f, 2f, 1f
3: mrs x2, sctlr_el3
b 0f
2: mrs x2, sctlr_el2
b 0f
1: mrs x2, sctlr_el1
0:
/* Unset CR_M | CR_C | CR_I from SCTLR to disable all caches */
movn x1, #(CR_M | CR_C | CR_I)
and x1, x2, x1
switch_el x4, 3f, 2f, 1f
3: msr sctlr_el3, x1
b 0f
2: msr sctlr_el2, x1
b 0f
1: msr sctlr_el1, x1
0: isb
/* This call only clobbers x30 (lr) and x9 (unused) */
mov x3, x30
bl __asm_invalidate_tlb_all
/* From here on we're running safely with caches disabled */
/* Set TTBR to our first argument */
switch_el x4, 3f, 2f, 1f
3: msr ttbr0_el3, x0
b 0f
2: msr ttbr0_el2, x0
b 0f
1: msr ttbr0_el1, x0
0: isb
/* Restore original SCTLR and thus enable caches again */
switch_el x4, 3f, 2f, 1f
3: msr sctlr_el3, x2
b 0f
2: msr sctlr_el2, x2
b 0f
1: msr sctlr_el1, x2
0: isb
ret x3
ENDPROC(__asm_switch_ttbr)
.popsection