Commit 06e7cbc2 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

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



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: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/89b5f974a7fa5011206682cd092e2c905530ff46.1632755552.git.christophe.leroy@csgroup.eu
parent 31284f70

arch/powerpc/kernel/head_40x.S

+8 −1
Original line number Diff line number Diff line
@@ -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>
@@ -650,7 +651,7 @@ 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:
@@ -687,6 +688,12 @@ 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