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authorHuacai Chen <chenhuacai@loongson.cn>2024-07-20 22:40:59 +0800
committerHuacai Chen <chenhuacai@loongson.cn>2024-07-20 22:40:59 +0800
commit8e02c3b782ec64343f3cccc8dc5a8be2b379e80b (patch)
treeb3dea31c724b20becad2cd2a892b304234573457 /arch/loongarch/kernel
parent614d7e99752e02ff6f6d447a83d2929b9649b6cb (diff)
LoongArch: Add writecombine support for DMW-based ioremap()
Currently, only TLB-based ioremap() support writecombine, so add the counterpart for DMW-based ioremap() with help of DMW2. The base address (WRITECOMBINE_BASE) is configured as 0xa000000000000000. DMW3 is unused by kernel now, however firmware may leave garbage in them and interfere kernel's address mapping. So clear it as necessary. BTW, centralize the DMW configuration to macro SETUP_DMWINS. Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Diffstat (limited to 'arch/loongarch/kernel')
-rw-r--r--arch/loongarch/kernel/head.S11
1 files changed, 2 insertions, 9 deletions
diff --git a/arch/loongarch/kernel/head.S b/arch/loongarch/kernel/head.S
index 4677ea8fa8e9..506a99a5bbc7 100644
--- a/arch/loongarch/kernel/head.S
+++ b/arch/loongarch/kernel/head.S
@@ -44,11 +44,7 @@ SYM_DATA(kernel_fsize, .long _kernel_fsize);
SYM_CODE_START(kernel_entry) # kernel entry point
/* Config direct window and set PG */
- li.d t0, CSR_DMW0_INIT # UC, PLV0, 0x8000 xxxx xxxx xxxx
- csrwr t0, LOONGARCH_CSR_DMWIN0
- li.d t0, CSR_DMW1_INIT # CA, PLV0, 0x9000 xxxx xxxx xxxx
- csrwr t0, LOONGARCH_CSR_DMWIN1
-
+ SETUP_DMWINS t0
JUMP_VIRT_ADDR t0, t1
/* Enable PG */
@@ -124,11 +120,8 @@ SYM_CODE_END(kernel_entry)
* function after setting up the stack and tp registers.
*/
SYM_CODE_START(smpboot_entry)
- li.d t0, CSR_DMW0_INIT # UC, PLV0
- csrwr t0, LOONGARCH_CSR_DMWIN0
- li.d t0, CSR_DMW1_INIT # CA, PLV0
- csrwr t0, LOONGARCH_CSR_DMWIN1
+ SETUP_DMWINS t0
JUMP_VIRT_ADDR t0, t1
#ifdef CONFIG_PAGE_SIZE_4KB