powerpc/40x: Map 32Mbytes of memory at startup

[ 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 <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/89b5f974a7fa5011206682cd092e2c905530ff46.1632755552.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Christophe Leroy
2021-09-27 17:12:39 +02:00
committed by Greg Kroah-Hartman
parent c330442f46
commit 21125e0116

View File

@@ -27,6 +27,7 @@
#include <linux/init.h> #include <linux/init.h>
#include <linux/pgtable.h> #include <linux/pgtable.h>
#include <linux/sizes.h>
#include <asm/processor.h> #include <asm/processor.h>
#include <asm/page.h> #include <asm/page.h>
#include <asm/mmu.h> #include <asm/mmu.h>
@@ -626,7 +627,7 @@ start_here:
b . /* prevent prefetch past rfi */ b . /* prevent prefetch past rfi */
/* Set up the initial MMU state so we can do the first level of /* 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. * virtual to physical and more importantly sets the cache mode.
*/ */
initial_mmu: initial_mmu:
@@ -663,6 +664,12 @@ initial_mmu:
tlbwe r4,r0,TLB_DATA /* Load the data portion of the entry */ tlbwe r4,r0,TLB_DATA /* Load the data portion of the entry */
tlbwe r3,r0,TLB_TAG /* Load the tag 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 isync
/* Establish the exception vector base /* Establish the exception vector base