[PATCH AUTOSEL 5.10 21/34] powerpc/40x: Map 32Mbytes of memory at startup
From: Sasha Levin <sashal@kernel.org>
Date: 2022-01-17 17:06:21
Also in:
lkml, stable
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
From: Christophe Leroy <redacted> [ Upstream commit 06e7cbc29e97b4713b4ea6def04ae8501a7d1a59 ] As reported by Carlo, 16Mbytes is not enough with modern kernels that tend to be a bit big, so map another 16M page at boot. Signed-off-by: Christophe Leroy <redacted> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/89b5f974a7fa5011206682cd092e2c905530ff46.1632755552.git.christophe.leroy@csgroup.eu (local) Signed-off-by: Sasha Levin <sashal@kernel.org> --- arch/powerpc/kernel/head_40x.S | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index a1ae00689e0f4..aeb9bc9958749 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S@@ -27,6 +27,7 @@ #include <linux/init.h> #include <linux/pgtable.h> +#include <linux/sizes.h> #include <asm/processor.h> #include <asm/page.h> #include <asm/mmu.h>
@@ -626,7 +627,7 @@ start_here: b . /* prevent prefetch past rfi */ /* Set up the initial MMU state so we can do the first level of - * kernel initialization. This maps the first 16 MBytes of memory 1:1 + * kernel initialization. This maps the first 32 MBytes of memory 1:1 * virtual to physical and more importantly sets the cache mode. */ initial_mmu:
@@ -663,6 +664,12 @@ initial_mmu: tlbwe r4,r0,TLB_DATA /* Load the data portion of the entry */ tlbwe r3,r0,TLB_TAG /* Load the tag portion of the entry */ + li r0,62 /* TLB slot 62 */ + addis r4,r4,SZ_16M@h + addis r3,r3,SZ_16M@h + tlbwe r4,r0,TLB_DATA /* Load the data portion of the entry */ + tlbwe r3,r0,TLB_TAG /* Load the tag portion of the entry */ + isync /* Establish the exception vector base
--
2.34.1