1 files changed, 497 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
new file mode 100644
index 0000000000..1a8cdafd68
--- /dev/null
+++ b/arch/powerpc/kernel/misc_64.S
@@ -0,0 +1,497 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * This file contains miscellaneous low-level functions.
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
+ * and Paul Mackerras.
+ * Adapted for iSeries by Mike Corrigan (mikejc@us.ibm.com)
+ * PPC64 updates by Dave Engebretsen (engebret@us.ibm.com)
+ */
+
+#include <linux/export.h>
+#include <linux/linkage.h>
+#include <linux/sys.h>
+#include <asm/unistd.h>
+#include <asm/errno.h>
+#include <asm/processor.h>
+#include <asm/page.h>
+#include <asm/cache.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/cputable.h>
+#include <asm/thread_info.h>
+#include <asm/kexec.h>
+#include <asm/ptrace.h>
+#include <asm/mmu.h>
+#include <asm/feature-fixups.h>
+
+	.text
+
+_GLOBAL(__bswapdi2)
+EXPORT_SYMBOL(__bswapdi2)
+	srdi	r8,r3,32
+	rlwinm	r7,r3,8,0xffffffff
+	rlwimi	r7,r3,24,0,7
+	rlwinm	r9,r8,8,0xffffffff
+	rlwimi	r7,r3,24,16,23
+	rlwimi	r9,r8,24,0,7
+	rlwimi	r9,r8,24,16,23
+	sldi	r7,r7,32
+	or	r3,r7,r9
+	blr
+
+
+#ifdef CONFIG_PPC_EARLY_DEBUG_BOOTX
+_GLOBAL(rmci_on)
+	sync
+	isync
+	li	r3,0x100
+	rldicl	r3,r3,32,0
+	mfspr	r5,SPRN_HID4
+	or	r5,r5,r3
+	sync
+	mtspr	SPRN_HID4,r5
+	isync
+	slbia
+	isync
+	sync
+	blr
+
+_GLOBAL(rmci_off)
+	sync
+	isync
+	li	r3,0x100
+	rldicl	r3,r3,32,0
+	mfspr	r5,SPRN_HID4
+	andc	r5,r5,r3
+	sync
+	mtspr	SPRN_HID4,r5
+	isync
+	slbia
+	isync
+	sync
+	blr
+#endif /* CONFIG_PPC_EARLY_DEBUG_BOOTX */
+
+#if defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE)
+
+/*
+ * Do an IO access in real mode
+ */
+_GLOBAL(real_readb)
+	mfmsr	r7
+	ori	r0,r7,MSR_DR
+	xori	r0,r0,MSR_DR
+	sync
+	mtmsrd	r0
+	sync
+	isync
+	mfspr	r6,SPRN_HID4
+	rldicl	r5,r6,32,0
+	ori	r5,r5,0x100
+	rldicl	r5,r5,32,0
+	sync
+	mtspr	SPRN_HID4,r5
+	isync
+	slbia
+	isync
+	lbz	r3,0(r3)
+	sync
+	mtspr	SPRN_HID4,r6
+	isync
+	slbia
+	isync
+	mtmsrd	r7
+	sync
+	isync
+	blr
+
+	/*
+ * Do an IO access in real mode
+ */
+_GLOBAL(real_writeb)
+	mfmsr	r7
+	ori	r0,r7,MSR_DR
+	xori	r0,r0,MSR_DR
+	sync
+	mtmsrd	r0
+	sync
+	isync
+	mfspr	r6,SPRN_HID4
+	rldicl	r5,r6,32,0
+	ori	r5,r5,0x100
+	rldicl	r5,r5,32,0
+	sync
+	mtspr	SPRN_HID4,r5
+	isync
+	slbia
+	isync
+	stb	r3,0(r4)
+	sync
+	mtspr	SPRN_HID4,r6
+	isync
+	slbia
+	isync
+	mtmsrd	r7
+	sync
+	isync
+	blr
+#endif /* defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE) */
+
+#ifdef CONFIG_PPC_PASEMI
+
+_GLOBAL(real_205_readb)
+	mfmsr	r7
+	ori	r0,r7,MSR_DR
+	xori	r0,r0,MSR_DR
+	sync
+	mtmsrd	r0
+	sync
+	isync
+	LBZCIX(R3,R0,R3)
+	isync
+	mtmsrd	r7
+	sync
+	isync
+	blr
+
+_GLOBAL(real_205_writeb)
+	mfmsr	r7
+	ori	r0,r7,MSR_DR
+	xori	r0,r0,MSR_DR
+	sync
+	mtmsrd	r0
+	sync
+	isync
+	STBCIX(R3,R0,R4)
+	isync
+	mtmsrd	r7
+	sync
+	isync
+	blr
+
+#endif /* CONFIG_PPC_PASEMI */
+
+
+#if defined(CONFIG_CPU_FREQ_PMAC64) || defined(CONFIG_CPU_FREQ_MAPLE)
+/*
+ * SCOM access functions for 970 (FX only for now)
+ *
+ * unsigned long scom970_read(unsigned int address);
+ * void scom970_write(unsigned int address, unsigned long value);
+ *
+ * The address passed in is the 24 bits register address. This code
+ * is 970 specific and will not check the status bits, so you should
+ * know what you are doing.
+ */
+_GLOBAL(scom970_read)
+	/* interrupts off */
+	mfmsr	r4
+	ori	r0,r4,MSR_EE
+	xori	r0,r0,MSR_EE
+	mtmsrd	r0,1
+
+	/* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits
+	 * (including parity). On current CPUs they must be 0'd,
+	 * and finally or in RW bit
+	 */
+	rlwinm	r3,r3,8,0,15
+	ori	r3,r3,0x8000
+
+	/* do the actual scom read */
+	sync
+	mtspr	SPRN_SCOMC,r3
+	isync
+	mfspr	r3,SPRN_SCOMD
+	isync
+	mfspr	r0,SPRN_SCOMC
+	isync
+
+	/* XXX:	fixup result on some buggy 970's (ouch ! we lost a bit, bah
+	 * that's the best we can do). Not implemented yet as we don't use
+	 * the scom on any of the bogus CPUs yet, but may have to be done
+	 * ultimately
+	 */
+
+	/* restore interrupts */
+	mtmsrd	r4,1
+	blr
+
+
+_GLOBAL(scom970_write)
+	/* interrupts off */
+	mfmsr	r5
+	ori	r0,r5,MSR_EE
+	xori	r0,r0,MSR_EE
+	mtmsrd	r0,1
+
+	/* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits
+	 * (including parity). On current CPUs they must be 0'd.
+	 */
+
+	rlwinm	r3,r3,8,0,15
+
+	sync
+	mtspr	SPRN_SCOMD,r4      /* write data */
+	isync
+	mtspr	SPRN_SCOMC,r3      /* write command */
+	isync
+	mfspr	3,SPRN_SCOMC
+	isync
+
+	/* restore interrupts */
+	mtmsrd	r5,1
+	blr
+#endif /* CONFIG_CPU_FREQ_PMAC64 || CONFIG_CPU_FREQ_MAPLE */
+
+/* kexec_wait(phys_cpu)
+ *
+ * wait for the flag to change, indicating this kernel is going away but
+ * the slave code for the next one is at addresses 0 to 100.
+ *
+ * This is used by all slaves, even those that did not find a matching
+ * paca in the secondary startup code.
+ *
+ * Physical (hardware) cpu id should be in r3.
+ */
+_GLOBAL(kexec_wait)
+	bcl	20,31,$+4
+1:	mflr	r5
+	addi	r5,r5,kexec_flag-1b
+
+99:	HMT_LOW
+#ifdef CONFIG_KEXEC_CORE	/* use no memory without kexec */
+	lwz	r4,0(r5)
+	cmpwi	0,r4,0
+	beq	99b
+#ifdef CONFIG_PPC_BOOK3S_64
+	li	r10,0x60
+	mfmsr	r11
+	clrrdi	r11,r11,1	/* Clear MSR_LE */
+	mtsrr0	r10
+	mtsrr1	r11
+	rfid
+#else
+	/* Create TLB entry in book3e_secondary_core_init */
+	li	r4,0
+	ba	0x60
+#endif
+#endif
+
+/* this can be in text because we won't change it until we are
+ * running in real anyways
+ */
+kexec_flag:
+	.long	0
+
+
+#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_PPC_BOOK3E_64
+/*
+ * BOOK3E has no real MMU mode, so we have to setup the initial TLB
+ * for a core to identity map v:0 to p:0.  This current implementation
+ * assumes that 1G is enough for kexec.
+ */
+kexec_create_tlb:
+	/*
+	 * Invalidate all non-IPROT TLB entries to avoid any TLB conflict.
+	 * IPROT TLB entries should be >= PAGE_OFFSET and thus not conflict.
+	 */
+	PPC_TLBILX_ALL(0,R0)
+	sync
+	isync
+
+	mfspr	r10,SPRN_TLB1CFG
+	andi.	r10,r10,TLBnCFG_N_ENTRY	/* Extract # entries */
+	subi	r10,r10,1	/* Last entry: no conflict with kernel text */
+	lis	r9,MAS0_TLBSEL(1)@h
+	rlwimi	r9,r10,16,4,15		/* Setup MAS0 = TLBSEL | ESEL(r9) */
+
+/* Set up a temp identity mapping v:0 to p:0 and return to it. */
+	mtspr	SPRN_MAS0,r9
+
+	lis	r9,(MAS1_VALID|MAS1_IPROT)@h
+	ori	r9,r9,(MAS1_TSIZE(BOOK3E_PAGESZ_1GB))@l
+	mtspr	SPRN_MAS1,r9
+
+	LOAD_REG_IMMEDIATE(r9, 0x0 | MAS2_M_IF_NEEDED)
+	mtspr	SPRN_MAS2,r9
+
+	LOAD_REG_IMMEDIATE(r9, 0x0 | MAS3_SR | MAS3_SW | MAS3_SX)
+	mtspr	SPRN_MAS3,r9
+	li	r9,0
+	mtspr	SPRN_MAS7,r9
+
+	tlbwe
+	isync
+	blr
+#endif
+
+/* kexec_smp_wait(void)
+ *
+ * call with interrupts off
+ * note: this is a terminal routine, it does not save lr
+ *
+ * get phys id from paca
+ * switch to real mode
+ * mark the paca as no longer used
+ * join other cpus in kexec_wait(phys_id)
+ */
+_GLOBAL(kexec_smp_wait)
+	lhz	r3,PACAHWCPUID(r13)
+	bl	real_mode
+
+	li	r4,KEXEC_STATE_REAL_MODE
+	stb	r4,PACAKEXECSTATE(r13)
+
+	b	kexec_wait
+
+/*
+ * switch to real mode (turn mmu off)
+ * we use the early kernel trick that the hardware ignores bits
+ * 0 and 1 (big endian) of the effective address in real mode
+ *
+ * don't overwrite r3 here, it is live for kexec_wait above.
+ */
+SYM_FUNC_START_LOCAL(real_mode)	/* assume normal blr return */
+#ifdef CONFIG_PPC_BOOK3E_64
+	/* Create an identity mapping. */
+	b	kexec_create_tlb
+#else
+1:	li	r9,MSR_RI
+	li	r10,MSR_DR|MSR_IR
+	mflr	r11		/* return address to SRR0 */
+	mfmsr	r12
+	andc	r9,r12,r9
+	andc	r10,r12,r10
+
+	mtmsrd	r9,1
+	mtspr	SPRN_SRR1,r10
+	mtspr	SPRN_SRR0,r11
+	rfid
+#endif
+SYM_FUNC_END(real_mode)
+
+/*
+ * kexec_sequence(newstack, start, image, control, clear_all(),
+	          copy_with_mmu_off)
+ *
+ * does the grungy work with stack switching and real mode switches
+ * also does simple calls to other code
+ */
+
+_GLOBAL(kexec_sequence)
+	mflr	r0
+	std	r0,16(r1)
+
+	/* switch stacks to newstack -- &kexec_stack.stack */
+	stdu	r1,THREAD_SIZE-STACK_FRAME_MIN_SIZE(r3)
+	mr	r1,r3
+
+	li	r0,0
+	std	r0,16(r1)
+
+	/* save regs for local vars on new stack.
+	 * yes, we won't go back, but ...
+	 */
+	std	r31,-8(r1)
+	std	r30,-16(r1)
+	std	r29,-24(r1)
+	std	r28,-32(r1)
+	std	r27,-40(r1)
+	std	r26,-48(r1)
+	std	r25,-56(r1)
+
+	stdu	r1,-STACK_FRAME_MIN_SIZE-64(r1)
+
+	/* save args into preserved regs */
+	mr	r31,r3			/* newstack (both) */
+	mr	r30,r4			/* start (real) */
+	mr	r29,r5			/* image (virt) */
+	mr	r28,r6			/* control, unused */
+	mr	r27,r7			/* clear_all() fn desc */
+	mr	r26,r8			/* copy_with_mmu_off */
+	lhz	r25,PACAHWCPUID(r13)	/* get our phys cpu from paca */
+
+	/* disable interrupts, we are overwriting kernel data next */
+#ifdef CONFIG_PPC_BOOK3E_64
+	wrteei	0
+#else
+	mfmsr	r3
+	rlwinm	r3,r3,0,17,15
+	mtmsrd	r3,1
+#endif
+
+	/* We need to turn the MMU off unless we are in hash mode
+	 * under a hypervisor
+	 */
+	cmpdi	r26,0
+	beq	1f
+	bl	real_mode
+1:
+	/* copy dest pages, flush whole dest image */
+	mr	r3,r29
+	bl	CFUNC(kexec_copy_flush)	/* (image) */
+
+	/* turn off mmu now if not done earlier */
+	cmpdi	r26,0
+	bne	1f
+	bl	real_mode
+
+	/* copy  0x100 bytes starting at start to 0 */
+1:	li	r3,0
+	mr	r4,r30		/* start, aka phys mem offset */
+	li	r5,0x100
+	li	r6,0
+	bl	copy_and_flush	/* (dest, src, copy limit, start offset) */
+1:	/* assume normal blr return */
+
+	/* release other cpus to the new kernel secondary start at 0x60 */
+	mflr	r5
+	li	r6,1
+	stw	r6,kexec_flag-1b(5)
+
+	cmpdi	r27,0
+	beq	1f
+
+	/* clear out hardware hash page table and tlb */
+#ifdef CONFIG_PPC64_ELF_ABI_V1
+	ld	r12,0(r27)		/* deref function descriptor */
+#else
+	mr	r12,r27
+#endif
+	mtctr	r12
+	bctrl				/* mmu_hash_ops.hpte_clear_all(void); */
+
+/*
+ *   kexec image calling is:
+ *      the first 0x100 bytes of the entry point are copied to 0
+ *
+ *      all slaves branch to slave = 0x60 (absolute)
+ *              slave(phys_cpu_id);
+ *
+ *      master goes to start = entry point
+ *              start(phys_cpu_id, start, 0);
+ *
+ *
+ *   a wrapper is needed to call existing kernels, here is an approximate
+ *   description of one method:
+ *
+ * v2: (2.6.10)
+ *   start will be near the boot_block (maybe 0x100 bytes before it?)
+ *   it will have a 0x60, which will b to boot_block, where it will wait
+ *   and 0 will store phys into struct boot-block and load r3 from there,
+ *   copy kernel 0-0x100 and tell slaves to back down to 0x60 again
+ *
+ * v1: (2.6.9)
+ *    boot block will have all cpus scanning device tree to see if they
+ *    are the boot cpu ?????
+ *    other device tree differences (prop sizes, va vs pa, etc)...
+ */
+1:	mr	r3,r25	# my phys cpu
+	mr	r4,r30	# start, aka phys mem offset
+	mtlr	4
+	li	r5,0
+	blr	/* image->start(physid, image->start, 0); */
+#endif /* CONFIG_KEXEC_CORE */