Commit 56e54b4e authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/32: Remove 'noltlbs' kernel parameter 



Mapping without large TLBs has no added value on the 8xx.

Mapping without large TLBs is still necessary on 40x when
selecting CONFIG_KFENCE or CONFIG_DEBUG_PAGEALLOC or
CONFIG_STRICT_KERNEL_RWX, but this is done automatically
and doesn't require user selection.

Remove 'noltlbs' kernel parameter, the user has no reason
to use it.

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/80ca17bd39cf608a8ebd0764d7064a498e131199.1655202721.git.christophe.leroy@csgroup.eu
parent 1ce84497

Documentation/admin-guide/kernel-parameters.txt

+0 −3
Original line number Diff line number Diff line
@@ -3661,9 +3661,6 @@ 


	nolapic_timer	[X86-32,APIC] Do not use the local APIC timer.



	noltlbs		[PPC] Do not use large page/tlb entries for kernel

			lowmem mapping on PPC40x and PPC8xx



	nomca		[IA-64] Disable machine check abort handling



	nomce		[X86-32] Disable Machine Check Exception

arch/powerpc/mm/init_32.c

+0 −3
Original line number Diff line number Diff line
@@ -79,9 +79,6 @@ unsigned long __max_low_memory = MAX_LOW_MEM; 
 */

static void __init MMU_setup(void)

{

	if (strstr(boot_command_line, "noltlbs")) {

		__map_without_ltlbs = 1;

	}

	if (IS_ENABLED(CONFIG_PPC_8xx))

		return;

arch/powerpc/mm/nohash/8xx.c

+0 −9
Original line number Diff line number Diff line
@@ -14,8 +14,6 @@ 


#define IMMR_SIZE (FIX_IMMR_SIZE << PAGE_SHIFT)



extern int __map_without_ltlbs;



static unsigned long block_mapped_ram;



/*
@@ -28,8 +26,6 @@ phys_addr_t v_block_mapped(unsigned long va) 


	if (va >= VIRT_IMMR_BASE && va < VIRT_IMMR_BASE + IMMR_SIZE)

		return p + va - VIRT_IMMR_BASE;

	if (__map_without_ltlbs)

		return 0;

	if (va >= PAGE_OFFSET && va < PAGE_OFFSET + block_mapped_ram)

		return __pa(va);

	return 0;
@@ -45,8 +41,6 @@ unsigned long p_block_mapped(phys_addr_t pa) 


	if (pa >= p && pa < p + IMMR_SIZE)

		return VIRT_IMMR_BASE + pa - p;

	if (__map_without_ltlbs)

		return 0;

	if (pa < block_mapped_ram)

		return (unsigned long)__va(pa);

	return 0;
@@ -153,9 +147,6 @@ unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top) 


	mmu_mapin_immr();



	if (__map_without_ltlbs)

		return 0;



	mmu_mapin_ram_chunk(0, boundary, PAGE_KERNEL_TEXT, true);

	if (debug_pagealloc_enabled_or_kfence()) {

		top = boundary;