powerpc: Remove core support for 40x

Now that 40x platforms have gone, remove support
for 40x in the core of powerpc arch.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240628121201.130802-4-mpe@ellerman.id.au

6 files changed, 5 insertions, 197 deletions

diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h
index 6949c2c937e7..b2d1eea09761 100644
--- a/arch/powerpc/mm/mmu_decl.h
+++ b/arch/powerpc/mm/mmu_decl.h
@@ -20,9 +20,9 @@
 #include <asm/trace.h>
 
 /*
- * On 40x and 8xx, we directly inline tlbia and tlbivax
+ * On 8xx, we directly inline tlbia
  */
-#if defined(CONFIG_40x) || defined(CONFIG_PPC_8xx)
+#ifdef CONFIG_PPC_8xx
 static inline void _tlbil_all(void)
 {
 	asm volatile ("sync; tlbia; isync" : : : "memory");
@@ -35,7 +35,7 @@ static inline void _tlbil_pid(unsigned int pid)
 }
 #define _tlbil_pid_noind(pid)	_tlbil_pid(pid)
 
-#else /* CONFIG_40x || CONFIG_PPC_8xx */
+#else /* CONFIG_PPC_8xx */
 extern void _tlbil_all(void);
 extern void _tlbil_pid(unsigned int pid);
 #ifdef CONFIG_PPC_BOOK3E_64
@@ -43,7 +43,7 @@ extern void _tlbil_pid_noind(unsigned int pid);
 #else
 #define _tlbil_pid_noind(pid)	_tlbil_pid(pid)
 #endif
-#endif /* !(CONFIG_40x || CONFIG_PPC_8xx) */
+#endif /* !CONFIG_PPC_8xx */
 
 /*
  * On 8xx, we directly inline tlbie, on others, it's extern
diff --git a/arch/powerpc/mm/nohash/40x.c b/arch/powerpc/mm/nohash/40x.c
deleted file mode 100644
index e835e80c09db..000000000000
--- a/arch/powerpc/mm/nohash/40x.c
+++ /dev/null
@@ -1,161 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * This file contains the routines for initializing the MMU
- * on the 4xx series of chips.
- *  -- paulus
- *
- *  Derived from arch/ppc/mm/init.c:
- *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
- *
- *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
- *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
- *    Copyright (C) 1996 Paul Mackerras
- *
- *  Derived from "arch/i386/mm/init.c"
- *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
- */
-
-#include <linux/signal.h>
-#include <linux/sched.h>
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/string.h>
-#include <linux/types.h>
-#include <linux/ptrace.h>
-#include <linux/mman.h>
-#include <linux/mm.h>
-#include <linux/swap.h>
-#include <linux/stddef.h>
-#include <linux/vmalloc.h>
-#include <linux/init.h>
-#include <linux/delay.h>
-#include <linux/highmem.h>
-#include <linux/memblock.h>
-
-#include <asm/io.h>
-#include <asm/mmu_context.h>
-#include <asm/mmu.h>
-#include <linux/uaccess.h>
-#include <asm/smp.h>
-#include <asm/bootx.h>
-#include <asm/machdep.h>
-#include <asm/setup.h>
-
-#include <mm/mmu_decl.h>
-
-/*
- * MMU_init_hw does the chip-specific initialization of the MMU hardware.
- */
-void __init MMU_init_hw(void)
-{
-	int i;
-	unsigned long zpr;
-
-	/*
-	 * The Zone Protection Register (ZPR) defines how protection will
-	 * be applied to every page which is a member of a given zone.
-	 * The zone index bits (of ZSEL) in the PTE are used for software
-	 * indicators. We use the 4 upper bits of virtual address to select
-	 * the zone. We set all zones above TASK_SIZE to zero, allowing
-	 * only kernel access as indicated in the PTE. For zones below
-	 * TASK_SIZE, we set a 01 binary (a value of 10 will not work)
-	 * to allow user access as indicated in the PTE.  This also allows
-	 * kernel access as indicated in the PTE.
-	 */
-
-	for (i = 0, zpr = 0; i < TASK_SIZE >> 28; i++)
-		zpr |= 1 << (30 - i * 2);
-
-	mtspr(SPRN_ZPR, zpr);
-
-	flush_instruction_cache();
-
-	/*
-	 * Set up the real-mode cache parameters for the exception vector
-	 * handlers (which are run in real-mode).
-	 */
-
-        mtspr(SPRN_DCWR, 0x00000000);	/* All caching is write-back */
-
-        /*
-	 * Cache instruction and data space where the exception
-	 * vectors and the kernel live in real-mode.
-	 */
-
-        mtspr(SPRN_DCCR, 0xFFFF0000);	/* 2GByte of data space at 0x0. */
-        mtspr(SPRN_ICCR, 0xFFFF0000);	/* 2GByte of instr. space at 0x0. */
-}
-
-#define LARGE_PAGE_SIZE_16M	(1<<24)
-#define LARGE_PAGE_SIZE_4M	(1<<22)
-
-unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top)
-{
-	unsigned long v, s, mapped;
-	phys_addr_t p;
-
-	v = KERNELBASE;
-	p = 0;
-	s = total_lowmem;
-
-	if (IS_ENABLED(CONFIG_KFENCE))
-		return 0;
-
-	if (debug_pagealloc_enabled())
-		return 0;
-
-	if (strict_kernel_rwx_enabled())
-		return 0;
-
-	while (s >= LARGE_PAGE_SIZE_16M) {
-		pmd_t *pmdp;
-		unsigned long val = p | _PMD_SIZE_16M | _PAGE_EXEC | _PAGE_RW;
-
-		pmdp = pmd_off_k(v);
-		*pmdp++ = __pmd(val);
-		*pmdp++ = __pmd(val);
-		*pmdp++ = __pmd(val);
-		*pmdp++ = __pmd(val);
-
-		v += LARGE_PAGE_SIZE_16M;
-		p += LARGE_PAGE_SIZE_16M;
-		s -= LARGE_PAGE_SIZE_16M;
-	}
-
-	while (s >= LARGE_PAGE_SIZE_4M) {
-		pmd_t *pmdp;
-		unsigned long val = p | _PMD_SIZE_4M | _PAGE_EXEC | _PAGE_RW;
-
-		pmdp = pmd_off_k(v);
-		*pmdp = __pmd(val);
-
-		v += LARGE_PAGE_SIZE_4M;
-		p += LARGE_PAGE_SIZE_4M;
-		s -= LARGE_PAGE_SIZE_4M;
-	}
-
-	mapped = total_lowmem - s;
-
-	/* If the size of RAM is not an exact power of two, we may not
-	 * have covered RAM in its entirety with 16 and 4 MiB
-	 * pages. Consequently, restrict the top end of RAM currently
-	 * allocable so that calls to the MEMBLOCK to allocate PTEs for "tail"
-	 * coverage with normal-sized pages (or other reasons) do not
-	 * attempt to allocate outside the allowed range.
-	 */
-	memblock_set_current_limit(mapped);
-
-	return mapped;
-}
-
-void setup_initial_memory_limit(phys_addr_t first_memblock_base,
-				phys_addr_t first_memblock_size)
-{
-	/* We don't currently support the first MEMBLOCK not mapping 0
-	 * physical on those processors
-	 */
-	BUG_ON(first_memblock_base != 0);
-
-	/* 40x can only access 16MB at the moment (see head_40x.S) */
-	memblock_set_current_limit(min_t(u64, first_memblock_size, 0x00800000));
-}
diff --git a/arch/powerpc/mm/nohash/Makefile b/arch/powerpc/mm/nohash/Makefile
index b3f0498dd42f..86d0fe434824 100644
--- a/arch/powerpc/mm/nohash/Makefile
+++ b/arch/powerpc/mm/nohash/Makefile
@@ -2,7 +2,6 @@
 
 obj-y				+= mmu_context.o tlb.o tlb_low.o kup.o
 obj-$(CONFIG_PPC_BOOK3E_64)  	+= tlb_low_64e.o book3e_pgtable.o
-obj-$(CONFIG_40x)		+= 40x.o
 obj-$(CONFIG_44x)		+= 44x.o
 obj-$(CONFIG_PPC_8xx)		+= 8xx.o
 obj-$(CONFIG_PPC_E500)		+= e500.o
diff --git a/arch/powerpc/mm/nohash/kup.c b/arch/powerpc/mm/nohash/kup.c
index e1f7de2e54ec..c20c4f357fbf 100644
--- a/arch/powerpc/mm/nohash/kup.c
+++ b/arch/powerpc/mm/nohash/kup.c
@@ -15,8 +15,6 @@
 void setup_kuap(bool disabled)
 {
 	if (disabled) {
-		if (IS_ENABLED(CONFIG_40x))
-			disable_kuep = true;
 		if (smp_processor_id() == boot_cpuid)
 			cur_cpu_spec->mmu_features &= ~MMU_FTR_KUAP;
 		return;
diff --git a/arch/powerpc/mm/nohash/mmu_context.c b/arch/powerpc/mm/nohash/mmu_context.c
index ccd5819b1bd9..92dc028aff1f 100644
--- a/arch/powerpc/mm/nohash/mmu_context.c
+++ b/arch/powerpc/mm/nohash/mmu_context.c
@@ -219,9 +219,6 @@ static void set_context(unsigned long id, pgd_t *pgd)
 		/* sync */
 		mb();
 	} else if (kuap_is_disabled()) {
-		if (IS_ENABLED(CONFIG_40x))
-			mb();	/* sync */
-
 		mtspr(SPRN_PID, id);
 		isync();
 	}
diff --git a/arch/powerpc/mm/nohash/tlb_low.S b/arch/powerpc/mm/nohash/tlb_low.S
index e1199608ff4d..c4d296e73731 100644
--- a/arch/powerpc/mm/nohash/tlb_low.S
+++ b/arch/powerpc/mm/nohash/tlb_low.S
@@ -32,32 +32,7 @@
 #include <asm/asm-compat.h>
 #include <asm/feature-fixups.h>
 
-#if defined(CONFIG_40x)
-
-/*
- * 40x implementation needs only tlbil_va
- */
-_GLOBAL(__tlbil_va)
-	/* We run the search with interrupts disabled because we have to change
-	 * the PID and I don't want to preempt when that happens.
-	 */
-	mfmsr	r5
-	mfspr	r6,SPRN_PID
-	wrteei	0
-	mtspr	SPRN_PID,r4
-	tlbsx.	r3, 0, r3
-	mtspr	SPRN_PID,r6
-	wrtee	r5
-	bne	1f
-	sync
-	/* There are only 64 TLB entries, so r3 < 64, which means bit 25 is
-	 * clear. Since 25 is the V bit in the TLB_TAG, loading this value
-	 * will invalidate the TLB entry. */
-	tlbwe	r3, r3, TLB_TAG
-	isync
-1:	blr
-
-#elif defined(CONFIG_PPC_8xx)
+#if defined(CONFIG_PPC_8xx)
 
 /*
  * Nothing to do for 8xx, everything is inline