Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 398 insertions, 0 deletions

diff --git a/arch/powerpc/kvm/tm.S b/arch/powerpc/kvm/tm.S
new file mode 100644
index 000000000..2158f61e3
--- /dev/null
+++ b/arch/powerpc/kvm/tm.S
@@ -0,0 +1,398 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ *
+ * Derived from book3s_hv_rmhandlers.S, which is:
+ *
+ * Copyright 2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
+ */
+
+#include <asm/reg.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/export.h>
+#include <asm/tm.h>
+#include <asm/cputable.h>
+
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+#define VCPU_GPRS_TM(reg) (((reg) * ULONG_SIZE) + VCPU_GPR_TM)
+
+/*
+ * Save transactional state and TM-related registers.
+ * Called with:
+ * - r3 pointing to the vcpu struct
+ * - r4 containing the MSR with current TS bits:
+ * 	(For HV KVM, it is VCPU_MSR ; For PR KVM, it is host MSR).
+ * - r5 containing a flag indicating that non-volatile registers
+ *	must be preserved.
+ * If r5 == 0, this can modify all checkpointed registers, but
+ * restores r1, r2 before exit.  If r5 != 0, this restores the
+ * MSR TM/FP/VEC/VSX bits to their state on entry.
+ */
+_GLOBAL(__kvmppc_save_tm)
+	mflr	r0
+	std	r0, PPC_LR_STKOFF(r1)
+	stdu    r1, -SWITCH_FRAME_SIZE(r1)
+
+	mr	r9, r3
+	cmpdi	cr7, r5, 0
+
+	/* Turn on TM. */
+	mfmsr	r8
+	mr	r10, r8
+	li	r0, 1
+	rldimi	r8, r0, MSR_TM_LG, 63-MSR_TM_LG
+	ori     r8, r8, MSR_FP
+	oris    r8, r8, (MSR_VEC | MSR_VSX)@h
+	mtmsrd	r8
+
+	rldicl. r4, r4, 64 - MSR_TS_S_LG, 62
+	beq	1f	/* TM not active in guest. */
+
+	std	r1, HSTATE_SCRATCH2(r13)
+	std	r3, HSTATE_SCRATCH1(r13)
+
+	/* Save CR on the stack - even if r5 == 0 we need to get cr7 back. */
+	mfcr	r6
+	SAVE_GPR(6, r1)
+
+	/* Save DSCR so we can restore it to avoid running with user value */
+	mfspr	r7, SPRN_DSCR
+	SAVE_GPR(7, r1)
+
+	/*
+	 * We are going to do treclaim., which will modify all checkpointed
+	 * registers.  Save the non-volatile registers on the stack if
+	 * preservation of non-volatile state has been requested.
+	 */
+	beq	cr7, 3f
+	SAVE_NVGPRS(r1)
+
+	/* MSR[TS] will be 0 (non-transactional) once we do treclaim. */
+	li	r0, 0
+	rldimi	r10, r0, MSR_TS_S_LG, 63 - MSR_TS_T_LG
+	SAVE_GPR(10, r1)	/* final MSR value */
+3:
+#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
+BEGIN_FTR_SECTION
+	/* Emulation of the treclaim instruction needs TEXASR before treclaim */
+	mfspr	r6, SPRN_TEXASR
+	std	r6, VCPU_ORIG_TEXASR(r3)
+END_FTR_SECTION_IFSET(CPU_FTR_P9_TM_HV_ASSIST)
+#endif
+
+	/* Clear the MSR RI since r1, r13 are all going to be foobar. */
+	li	r5, 0
+	mtmsrd	r5, 1
+
+	li	r3, TM_CAUSE_KVM_RESCHED
+
+	/* All GPRs are volatile at this point. */
+	TRECLAIM(R3)
+
+	/* Temporarily store r13 and r9 so we have some regs to play with */
+	SET_SCRATCH0(r13)
+	GET_PACA(r13)
+	std	r9, PACATMSCRATCH(r13)
+	ld	r9, HSTATE_SCRATCH1(r13)
+
+	/* Save away PPR soon so we don't run with user value. */
+	std	r0, VCPU_GPRS_TM(0)(r9)
+	mfspr	r0, SPRN_PPR
+	HMT_MEDIUM
+
+	/* Reload stack pointer. */
+	std	r1, VCPU_GPRS_TM(1)(r9)
+	ld	r1, HSTATE_SCRATCH2(r13)
+
+	/* Set MSR RI now we have r1 and r13 back. */
+	std	r2, VCPU_GPRS_TM(2)(r9)
+	li	r2, MSR_RI
+	mtmsrd	r2, 1
+
+	/* Reload TOC pointer. */
+	LOAD_PACA_TOC()
+
+	/* Save all but r0-r2, r9 & r13 */
+	reg = 3
+	.rept	29
+	.if (reg != 9) && (reg != 13)
+	std	reg, VCPU_GPRS_TM(reg)(r9)
+	.endif
+	reg = reg + 1
+	.endr
+	/* ... now save r13 */
+	GET_SCRATCH0(r4)
+	std	r4, VCPU_GPRS_TM(13)(r9)
+	/* ... and save r9 */
+	ld	r4, PACATMSCRATCH(r13)
+	std	r4, VCPU_GPRS_TM(9)(r9)
+
+	/* Restore host DSCR and CR values, after saving guest values */
+	mfcr	r6
+	mfspr	r7, SPRN_DSCR
+	stw	r6, VCPU_CR_TM(r9)
+	std	r7, VCPU_DSCR_TM(r9)
+	REST_GPR(6, r1)
+	REST_GPR(7, r1)
+	mtcr	r6
+	mtspr	SPRN_DSCR, r7
+
+	/* Save away checkpointed SPRs. */
+	std	r0, VCPU_PPR_TM(r9)
+	mflr	r5
+	mfctr	r7
+	mfspr	r8, SPRN_AMR
+	mfspr	r10, SPRN_TAR
+	mfxer	r11
+	std	r5, VCPU_LR_TM(r9)
+	std	r7, VCPU_CTR_TM(r9)
+	std	r8, VCPU_AMR_TM(r9)
+	std	r10, VCPU_TAR_TM(r9)
+	std	r11, VCPU_XER_TM(r9)
+
+	/* Save FP/VSX. */
+	addi	r3, r9, VCPU_FPRS_TM
+	bl	store_fp_state
+	addi	r3, r9, VCPU_VRS_TM
+	bl	store_vr_state
+	mfspr	r6, SPRN_VRSAVE
+	stw	r6, VCPU_VRSAVE_TM(r9)
+
+	/* Restore non-volatile registers if requested to */
+	beq	cr7, 1f
+	REST_NVGPRS(r1)
+	REST_GPR(10, r1)
+1:
+	/*
+	 * We need to save these SPRs after the treclaim so that the software
+	 * error code is recorded correctly in the TEXASR.  Also the user may
+	 * change these outside of a transaction, so they must always be
+	 * context switched.
+	 */
+	mfspr	r7, SPRN_TEXASR
+	std	r7, VCPU_TEXASR(r9)
+	mfspr	r5, SPRN_TFHAR
+	mfspr	r6, SPRN_TFIAR
+	std	r5, VCPU_TFHAR(r9)
+	std	r6, VCPU_TFIAR(r9)
+
+	/* Restore MSR state if requested */
+	beq	cr7, 2f
+	mtmsrd	r10, 0
+2:
+	addi	r1, r1, SWITCH_FRAME_SIZE
+	ld	r0, PPC_LR_STKOFF(r1)
+	mtlr	r0
+	blr
+
+/*
+ * _kvmppc_save_tm_pr() is a wrapper around __kvmppc_save_tm(), so that it can
+ * be invoked from C function by PR KVM only.
+ */
+_GLOBAL(_kvmppc_save_tm_pr)
+	mflr	r0
+	std	r0, PPC_LR_STKOFF(r1)
+	stdu    r1, -PPC_MIN_STKFRM(r1)
+
+	mfspr   r8, SPRN_TAR
+	std	r8, PPC_MIN_STKFRM-8(r1)
+
+	li	r5, 1		/* preserve non-volatile registers */
+	bl	__kvmppc_save_tm
+
+	ld	r8, PPC_MIN_STKFRM-8(r1)
+	mtspr   SPRN_TAR, r8
+
+	addi    r1, r1, PPC_MIN_STKFRM
+	ld	r0, PPC_LR_STKOFF(r1)
+	mtlr	r0
+	blr
+
+EXPORT_SYMBOL_GPL(_kvmppc_save_tm_pr);
+
+/*
+ * Restore transactional state and TM-related registers.
+ * Called with:
+ *  - r3 pointing to the vcpu struct.
+ *  - r4 is the guest MSR with desired TS bits:
+ * 	For HV KVM, it is VCPU_MSR
+ * 	For PR KVM, it is provided by caller
+ * - r5 containing a flag indicating that non-volatile registers
+ *	must be preserved.
+ * If r5 == 0, this potentially modifies all checkpointed registers, but
+ * restores r1, r2 from the PACA before exit.
+ * If r5 != 0, this restores the MSR TM/FP/VEC/VSX bits to their state on entry.
+ */
+_GLOBAL(__kvmppc_restore_tm)
+	mflr	r0
+	std	r0, PPC_LR_STKOFF(r1)
+
+	cmpdi	cr7, r5, 0
+
+	/* Turn on TM/FP/VSX/VMX so we can restore them. */
+	mfmsr	r5
+	mr	r10, r5
+	li	r6, MSR_TM >> 32
+	sldi	r6, r6, 32
+	or	r5, r5, r6
+	ori	r5, r5, MSR_FP
+	oris	r5, r5, (MSR_VEC | MSR_VSX)@h
+	mtmsrd	r5
+
+	/*
+	 * The user may change these outside of a transaction, so they must
+	 * always be context switched.
+	 */
+	ld	r5, VCPU_TFHAR(r3)
+	ld	r6, VCPU_TFIAR(r3)
+	ld	r7, VCPU_TEXASR(r3)
+	mtspr	SPRN_TFHAR, r5
+	mtspr	SPRN_TFIAR, r6
+	mtspr	SPRN_TEXASR, r7
+
+	mr	r5, r4
+	rldicl. r5, r5, 64 - MSR_TS_S_LG, 62
+	beq	9f		/* TM not active in guest */
+
+	/* Make sure the failure summary is set, otherwise we'll program check
+	 * when we trechkpt.  It's possible that this might have been not set
+	 * on a kvmppc_set_one_reg() call but we shouldn't let this crash the
+	 * host.
+	 */
+	oris	r7, r7, (TEXASR_FS)@h
+	mtspr	SPRN_TEXASR, r7
+
+	/*
+	 * Make a stack frame and save non-volatile registers if requested.
+	 */
+	stdu	r1, -SWITCH_FRAME_SIZE(r1)
+	std	r1, HSTATE_SCRATCH2(r13)
+
+	mfcr	r6
+	mfspr	r7, SPRN_DSCR
+	SAVE_GPR(2, r1)
+	SAVE_GPR(6, r1)
+	SAVE_GPR(7, r1)
+
+	beq	cr7, 4f
+	SAVE_NVGPRS(r1)
+
+	/* MSR[TS] will be 1 (suspended) once we do trechkpt */
+	li	r0, 1
+	rldimi	r10, r0, MSR_TS_S_LG, 63 - MSR_TS_T_LG
+	SAVE_GPR(10, r1)	/* final MSR value */
+4:
+	/*
+	 * We need to load up the checkpointed state for the guest.
+	 * We need to do this early as it will blow away any GPRs, VSRs and
+	 * some SPRs.
+	 */
+
+	mr	r31, r3
+	addi	r3, r31, VCPU_FPRS_TM
+	bl	load_fp_state
+	addi	r3, r31, VCPU_VRS_TM
+	bl	load_vr_state
+	mr	r3, r31
+	lwz	r7, VCPU_VRSAVE_TM(r3)
+	mtspr	SPRN_VRSAVE, r7
+
+	ld	r5, VCPU_LR_TM(r3)
+	lwz	r6, VCPU_CR_TM(r3)
+	ld	r7, VCPU_CTR_TM(r3)
+	ld	r8, VCPU_AMR_TM(r3)
+	ld	r9, VCPU_TAR_TM(r3)
+	ld	r10, VCPU_XER_TM(r3)
+	mtlr	r5
+	mtcr	r6
+	mtctr	r7
+	mtspr	SPRN_AMR, r8
+	mtspr	SPRN_TAR, r9
+	mtxer	r10
+
+	/*
+	 * Load up PPR and DSCR values but don't put them in the actual SPRs
+	 * till the last moment to avoid running with userspace PPR and DSCR for
+	 * too long.
+	 */
+	ld	r29, VCPU_DSCR_TM(r3)
+	ld	r30, VCPU_PPR_TM(r3)
+
+	/* Clear the MSR RI since r1, r13 are all going to be foobar. */
+	li	r5, 0
+	mtmsrd	r5, 1
+
+	/* Load GPRs r0-r28 */
+	reg = 0
+	.rept	29
+	ld	reg, VCPU_GPRS_TM(reg)(r31)
+	reg = reg + 1
+	.endr
+
+	mtspr	SPRN_DSCR, r29
+	mtspr	SPRN_PPR, r30
+
+	/* Load final GPRs */
+	ld	29, VCPU_GPRS_TM(29)(r31)
+	ld	30, VCPU_GPRS_TM(30)(r31)
+	ld	31, VCPU_GPRS_TM(31)(r31)
+
+	/* TM checkpointed state is now setup.  All GPRs are now volatile. */
+	TRECHKPT
+
+	/* Now let's get back the state we need. */
+	HMT_MEDIUM
+	GET_PACA(r13)
+	ld	r1, HSTATE_SCRATCH2(r13)
+	REST_GPR(7, r1)
+	mtspr	SPRN_DSCR, r7
+
+	/* Set the MSR RI since we have our registers back. */
+	li	r5, MSR_RI
+	mtmsrd	r5, 1
+
+	/* Restore TOC pointer and CR */
+	REST_GPR(2, r1)
+	REST_GPR(6, r1)
+	mtcr	r6
+
+	/* Restore non-volatile registers if requested to. */
+	beq	cr7, 5f
+	REST_GPR(10, r1)
+	REST_NVGPRS(r1)
+
+5:	addi	r1, r1, SWITCH_FRAME_SIZE
+	ld	r0, PPC_LR_STKOFF(r1)
+	mtlr	r0
+
+9:	/* Restore MSR bits if requested */
+	beqlr	cr7
+	mtmsrd	r10, 0
+	blr
+
+/*
+ * _kvmppc_restore_tm_pr() is a wrapper around __kvmppc_restore_tm(), so that it
+ * can be invoked from C function by PR KVM only.
+ */
+_GLOBAL(_kvmppc_restore_tm_pr)
+	mflr	r0
+	std	r0, PPC_LR_STKOFF(r1)
+	stdu    r1, -PPC_MIN_STKFRM(r1)
+
+	/* save TAR so that it can be recovered later */
+	mfspr   r8, SPRN_TAR
+	std	r8, PPC_MIN_STKFRM-8(r1)
+
+	li	r5, 1
+	bl	__kvmppc_restore_tm
+
+	ld	r8, PPC_MIN_STKFRM-8(r1)
+	mtspr   SPRN_TAR, r8
+
+	addi    r1, r1, PPC_MIN_STKFRM
+	ld	r0, PPC_LR_STKOFF(r1)
+	mtlr	r0
+	blr
+
+EXPORT_SYMBOL_GPL(_kvmppc_restore_tm_pr);
+#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */