powerpc/32: Remove 'noltlbs' kernel parameter

[ Upstream commit 56e54b4e6c477b2a7df43f9a320ae5f9a5bfb16c ]

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: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/80ca17bd39cf608a8ebd0764d7064a498e131199.1655202721.git.christophe.leroy@csgroup.eu
Stable-dep-of: f9f2bff64c2f ("powerpc/8xx: Fix initial memory mapping")
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index e2c2ccba6e388c727f188723ea72d6a127d3511a..c22a8ee02e73b682f8a1f349ff2dfa4a65a3701b 100644 (file)
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3626,9 +3626,6 @@
 
        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

diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c
index b702f2b6429578c35e7417f83a74776360d25de0..967432d1b6c788af9ec7d4726434abd6c696b140 100644 (file)
--- a/arch/powerpc/mm/init_32.c
+++ b/arch/powerpc/mm/init_32.c
@@ -80,9 +80,6 @@ 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;
 

diff --git a/arch/powerpc/mm/nohash/8xx.c b/arch/powerpc/mm/nohash/8xx.c
index 5348e1f9eb9404276c7876a7238a2b65e0af57ca..94efd4fa6e768466c2027265e6c4bb9d43ad65f3 100644 (file)
--- a/arch/powerpc/mm/nohash/8xx.c
+++ b/arch/powerpc/mm/nohash/8xx.c
@@ -18,8 +18,6 @@
 
 #define IMMR_SIZE (FIX_IMMR_SIZE << PAGE_SHIFT)
 
-extern int __map_without_ltlbs;
-
 static unsigned long block_mapped_ram;
 
 /*
@@ -32,8 +30,6 @@ 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;
@@ -49,8 +45,6 @@ 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;
@@ -157,9 +151,6 @@ 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;