[PATCH 5.10 249/563] powerpc/64s: Convert some cpu_setup() and cpu_restore() functions to C

From: Greg Kroah-Hartman
Date: Mon Jan 24 2022 - 16:07:35 EST


From: Jordan Niethe <jniethe5@xxxxxxxxx>

[ Upstream commit 344fbab991a568dc33ad90711b489d870e18d26d ]

The only thing keeping the cpu_setup() and cpu_restore() functions
used in the cputable entries for Power7, Power8, Power9 and Power10 in
assembly was cpu_restore() being called before there was a stack in
generic_secondary_smp_init(). Commit ("powerpc/64: Set up a kernel
stack for secondaries before cpu_restore()") means that it is now
possible to use C.

Rewrite the functions in C so they are a little bit easier to read.
This is not changing their functionality.

Signed-off-by: Jordan Niethe <jniethe5@xxxxxxxxx>
[mpe: Tweak copyright and authorship notes]
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20201014072837.24539-2-jniethe5@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/powerpc/include/asm/cpu_setup_power.h | 12 +
arch/powerpc/kernel/cpu_setup_power.S | 252 -------------------
arch/powerpc/kernel/cpu_setup_power.c | 271 +++++++++++++++++++++
arch/powerpc/kernel/cputable.c | 12 +-
4 files changed, 287 insertions(+), 260 deletions(-)
create mode 100644 arch/powerpc/include/asm/cpu_setup_power.h
delete mode 100644 arch/powerpc/kernel/cpu_setup_power.S
create mode 100644 arch/powerpc/kernel/cpu_setup_power.c

diff --git a/arch/powerpc/include/asm/cpu_setup_power.h b/arch/powerpc/include/asm/cpu_setup_power.h
new file mode 100644
index 0000000000000..24be9131f8032
--- /dev/null
+++ b/arch/powerpc/include/asm/cpu_setup_power.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2020 IBM Corporation
+ */
+void __setup_cpu_power7(unsigned long offset, struct cpu_spec *spec);
+void __restore_cpu_power7(void);
+void __setup_cpu_power8(unsigned long offset, struct cpu_spec *spec);
+void __restore_cpu_power8(void);
+void __setup_cpu_power9(unsigned long offset, struct cpu_spec *spec);
+void __restore_cpu_power9(void);
+void __setup_cpu_power10(unsigned long offset, struct cpu_spec *spec);
+void __restore_cpu_power10(void);
diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cpu_setup_power.S
deleted file mode 100644
index 704e8b9501eee..0000000000000
--- a/arch/powerpc/kernel/cpu_setup_power.S
+++ /dev/null
@@ -1,252 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-/*
- * This file contains low level CPU setup functions.
- * Copyright (C) 2003 Benjamin Herrenschmidt (benh@xxxxxxxxxxxxxxxxxxx)
- */
-
-#include <asm/processor.h>
-#include <asm/page.h>
-#include <asm/cputable.h>
-#include <asm/ppc_asm.h>
-#include <asm/asm-offsets.h>
-#include <asm/cache.h>
-#include <asm/book3s/64/mmu-hash.h>
-
-/* Entry: r3 = crap, r4 = ptr to cputable entry
- *
- * Note that we can be called twice for pseudo-PVRs
- */
-_GLOBAL(__setup_cpu_power7)
- mflr r11
- bl __init_hvmode_206
- mtlr r11
- beqlr
- li r0,0
- mtspr SPRN_LPID,r0
- LOAD_REG_IMMEDIATE(r0, PCR_MASK)
- mtspr SPRN_PCR,r0
- mfspr r3,SPRN_LPCR
- li r4,(LPCR_LPES1 >> LPCR_LPES_SH)
- bl __init_LPCR_ISA206
- mtlr r11
- blr
-
-_GLOBAL(__restore_cpu_power7)
- mflr r11
- mfmsr r3
- rldicl. r0,r3,4,63
- beqlr
- li r0,0
- mtspr SPRN_LPID,r0
- LOAD_REG_IMMEDIATE(r0, PCR_MASK)
- mtspr SPRN_PCR,r0
- mfspr r3,SPRN_LPCR
- li r4,(LPCR_LPES1 >> LPCR_LPES_SH)
- bl __init_LPCR_ISA206
- mtlr r11
- blr
-
-_GLOBAL(__setup_cpu_power8)
- mflr r11
- bl __init_FSCR
- bl __init_PMU
- bl __init_PMU_ISA207
- bl __init_hvmode_206
- mtlr r11
- beqlr
- li r0,0
- mtspr SPRN_LPID,r0
- LOAD_REG_IMMEDIATE(r0, PCR_MASK)
- mtspr SPRN_PCR,r0
- mfspr r3,SPRN_LPCR
- ori r3, r3, LPCR_PECEDH
- li r4,0 /* LPES = 0 */
- bl __init_LPCR_ISA206
- bl __init_HFSCR
- bl __init_PMU_HV
- bl __init_PMU_HV_ISA207
- mtlr r11
- blr
-
-_GLOBAL(__restore_cpu_power8)
- mflr r11
- bl __init_FSCR
- bl __init_PMU
- bl __init_PMU_ISA207
- mfmsr r3
- rldicl. r0,r3,4,63
- mtlr r11
- beqlr
- li r0,0
- mtspr SPRN_LPID,r0
- LOAD_REG_IMMEDIATE(r0, PCR_MASK)
- mtspr SPRN_PCR,r0
- mfspr r3,SPRN_LPCR
- ori r3, r3, LPCR_PECEDH
- li r4,0 /* LPES = 0 */
- bl __init_LPCR_ISA206
- bl __init_HFSCR
- bl __init_PMU_HV
- bl __init_PMU_HV_ISA207
- mtlr r11
- blr
-
-_GLOBAL(__setup_cpu_power10)
- mflr r11
- bl __init_FSCR_power10
- bl __init_PMU
- bl __init_PMU_ISA31
- b 1f
-
-_GLOBAL(__setup_cpu_power9)
- mflr r11
- bl __init_FSCR_power9
- bl __init_PMU
-1: bl __init_hvmode_206
- mtlr r11
- beqlr
- li r0,0
- mtspr SPRN_PSSCR,r0
- mtspr SPRN_LPID,r0
- mtspr SPRN_PID,r0
- LOAD_REG_IMMEDIATE(r0, PCR_MASK)
- mtspr SPRN_PCR,r0
- mfspr r3,SPRN_LPCR
- LOAD_REG_IMMEDIATE(r4, LPCR_PECEDH | LPCR_PECE_HVEE | LPCR_HVICE | LPCR_HEIC)
- or r3, r3, r4
- LOAD_REG_IMMEDIATE(r4, LPCR_UPRT | LPCR_HR)
- andc r3, r3, r4
- li r4,0 /* LPES = 0 */
- bl __init_LPCR_ISA300
- bl __init_HFSCR
- bl __init_PMU_HV
- mtlr r11
- blr
-
-_GLOBAL(__restore_cpu_power10)
- mflr r11
- bl __init_FSCR_power10
- bl __init_PMU
- bl __init_PMU_ISA31
- b 1f
-
-_GLOBAL(__restore_cpu_power9)
- mflr r11
- bl __init_FSCR_power9
- bl __init_PMU
-1: mfmsr r3
- rldicl. r0,r3,4,63
- mtlr r11
- beqlr
- li r0,0
- mtspr SPRN_PSSCR,r0
- mtspr SPRN_LPID,r0
- mtspr SPRN_PID,r0
- LOAD_REG_IMMEDIATE(r0, PCR_MASK)
- mtspr SPRN_PCR,r0
- mfspr r3,SPRN_LPCR
- LOAD_REG_IMMEDIATE(r4, LPCR_PECEDH | LPCR_PECE_HVEE | LPCR_HVICE | LPCR_HEIC)
- or r3, r3, r4
- LOAD_REG_IMMEDIATE(r4, LPCR_UPRT | LPCR_HR)
- andc r3, r3, r4
- li r4,0 /* LPES = 0 */
- bl __init_LPCR_ISA300
- bl __init_HFSCR
- bl __init_PMU_HV
- mtlr r11
- blr
-
-__init_hvmode_206:
- /* Disable CPU_FTR_HVMODE and exit if MSR:HV is not set */
- mfmsr r3
- rldicl. r0,r3,4,63
- bnelr
- ld r5,CPU_SPEC_FEATURES(r4)
- LOAD_REG_IMMEDIATE(r6,CPU_FTR_HVMODE | CPU_FTR_P9_TM_HV_ASSIST)
- andc r5,r5,r6
- std r5,CPU_SPEC_FEATURES(r4)
- blr
-
-__init_LPCR_ISA206:
- /* Setup a sane LPCR:
- * Called with initial LPCR in R3 and desired LPES 2-bit value in R4
- *
- * LPES = 0b01 (HSRR0/1 used for 0x500)
- * PECE = 0b111
- * DPFD = 4
- * HDICE = 0
- * VC = 0b100 (VPM0=1, VPM1=0, ISL=0)
- * VRMASD = 0b10000 (L=1, LP=00)
- *
- * Other bits untouched for now
- */
- li r5,0x10
- rldimi r3,r5, LPCR_VRMASD_SH, 64-LPCR_VRMASD_SH-5
-
- /* POWER9 has no VRMASD */
-__init_LPCR_ISA300:
- rldimi r3,r4, LPCR_LPES_SH, 64-LPCR_LPES_SH-2
- ori r3,r3,(LPCR_PECE0|LPCR_PECE1|LPCR_PECE2)
- li r5,4
- rldimi r3,r5, LPCR_DPFD_SH, 64-LPCR_DPFD_SH-3
- clrrdi r3,r3,1 /* clear HDICE */
- li r5,4
- rldimi r3,r5, LPCR_VC_SH, 0
- mtspr SPRN_LPCR,r3
- isync
- blr
-
-__init_FSCR_power10:
- mfspr r3, SPRN_FSCR
- ori r3, r3, FSCR_PREFIX
- mtspr SPRN_FSCR, r3
- // fall through
-
-__init_FSCR_power9:
- mfspr r3, SPRN_FSCR
- ori r3, r3, FSCR_SCV
- mtspr SPRN_FSCR, r3
- // fall through
-
-__init_FSCR:
- mfspr r3,SPRN_FSCR
- ori r3,r3,FSCR_TAR|FSCR_EBB
- mtspr SPRN_FSCR,r3
- blr
-
-__init_HFSCR:
- mfspr r3,SPRN_HFSCR
- ori r3,r3,HFSCR_TAR|HFSCR_TM|HFSCR_BHRB|HFSCR_PM|\
- HFSCR_DSCR|HFSCR_VECVSX|HFSCR_FP|HFSCR_EBB|HFSCR_MSGP
- mtspr SPRN_HFSCR,r3
- blr
-
-__init_PMU_HV:
- li r5,0
- mtspr SPRN_MMCRC,r5
- blr
-
-__init_PMU_HV_ISA207:
- li r5,0
- mtspr SPRN_MMCRH,r5
- blr
-
-__init_PMU:
- li r5,0
- mtspr SPRN_MMCRA,r5
- mtspr SPRN_MMCR0,r5
- mtspr SPRN_MMCR1,r5
- mtspr SPRN_MMCR2,r5
- blr
-
-__init_PMU_ISA207:
- li r5,0
- mtspr SPRN_MMCRS,r5
- blr
-
-__init_PMU_ISA31:
- li r5,0
- mtspr SPRN_MMCR3,r5
- LOAD_REG_IMMEDIATE(r5, MMCRA_BHRB_DISABLE)
- mtspr SPRN_MMCRA,r5
- blr
diff --git a/arch/powerpc/kernel/cpu_setup_power.c b/arch/powerpc/kernel/cpu_setup_power.c
new file mode 100644
index 0000000000000..0c2191ee139ec
--- /dev/null
+++ b/arch/powerpc/kernel/cpu_setup_power.c
@@ -0,0 +1,271 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2020, Jordan Niethe, IBM Corporation.
+ *
+ * This file contains low level CPU setup functions.
+ * Originally written in assembly by Benjamin Herrenschmidt & various other
+ * authors.
+ */
+
+#include <asm/reg.h>
+#include <asm/synch.h>
+#include <linux/bitops.h>
+#include <asm/cputable.h>
+#include <asm/cpu_setup_power.h>
+
+/* Disable CPU_FTR_HVMODE and return false if MSR:HV is not set */
+static bool init_hvmode_206(struct cpu_spec *t)
+{
+ u64 msr;
+
+ msr = mfmsr();
+ if (msr & MSR_HV)
+ return true;
+
+ t->cpu_features &= ~(CPU_FTR_HVMODE | CPU_FTR_P9_TM_HV_ASSIST);
+ return false;
+}
+
+static void init_LPCR_ISA300(u64 lpcr, u64 lpes)
+{
+ /* POWER9 has no VRMASD */
+ lpcr |= (lpes << LPCR_LPES_SH) & LPCR_LPES;
+ lpcr |= LPCR_PECE0|LPCR_PECE1|LPCR_PECE2;
+ lpcr |= (4ull << LPCR_DPFD_SH) & LPCR_DPFD;
+ lpcr &= ~LPCR_HDICE; /* clear HDICE */
+ lpcr |= (4ull << LPCR_VC_SH);
+ mtspr(SPRN_LPCR, lpcr);
+ isync();
+}
+
+/*
+ * Setup a sane LPCR:
+ * Called with initial LPCR and desired LPES 2-bit value
+ *
+ * LPES = 0b01 (HSRR0/1 used for 0x500)
+ * PECE = 0b111
+ * DPFD = 4
+ * HDICE = 0
+ * VC = 0b100 (VPM0=1, VPM1=0, ISL=0)
+ * VRMASD = 0b10000 (L=1, LP=00)
+ *
+ * Other bits untouched for now
+ */
+static void init_LPCR_ISA206(u64 lpcr, u64 lpes)
+{
+ lpcr |= (0x10ull << LPCR_VRMASD_SH) & LPCR_VRMASD;
+ init_LPCR_ISA300(lpcr, lpes);
+}
+
+static void init_FSCR(void)
+{
+ u64 fscr;
+
+ fscr = mfspr(SPRN_FSCR);
+ fscr |= FSCR_TAR|FSCR_EBB;
+ mtspr(SPRN_FSCR, fscr);
+}
+
+static void init_FSCR_power9(void)
+{
+ u64 fscr;
+
+ fscr = mfspr(SPRN_FSCR);
+ fscr |= FSCR_SCV;
+ mtspr(SPRN_FSCR, fscr);
+ init_FSCR();
+}
+
+static void init_FSCR_power10(void)
+{
+ u64 fscr;
+
+ fscr = mfspr(SPRN_FSCR);
+ fscr |= FSCR_PREFIX;
+ mtspr(SPRN_FSCR, fscr);
+ init_FSCR_power9();
+}
+
+static void init_HFSCR(void)
+{
+ u64 hfscr;
+
+ hfscr = mfspr(SPRN_HFSCR);
+ hfscr |= HFSCR_TAR|HFSCR_TM|HFSCR_BHRB|HFSCR_PM|HFSCR_DSCR|\
+ HFSCR_VECVSX|HFSCR_FP|HFSCR_EBB|HFSCR_MSGP;
+ mtspr(SPRN_HFSCR, hfscr);
+}
+
+static void init_PMU_HV(void)
+{
+ mtspr(SPRN_MMCRC, 0);
+}
+
+static void init_PMU_HV_ISA207(void)
+{
+ mtspr(SPRN_MMCRH, 0);
+}
+
+static void init_PMU(void)
+{
+ mtspr(SPRN_MMCRA, 0);
+ mtspr(SPRN_MMCR0, 0);
+ mtspr(SPRN_MMCR1, 0);
+ mtspr(SPRN_MMCR2, 0);
+}
+
+static void init_PMU_ISA207(void)
+{
+ mtspr(SPRN_MMCRS, 0);
+}
+
+static void init_PMU_ISA31(void)
+{
+ mtspr(SPRN_MMCR3, 0);
+ mtspr(SPRN_MMCRA, MMCRA_BHRB_DISABLE);
+}
+
+/*
+ * Note that we can be called twice of pseudo-PVRs.
+ * The parameter offset is not used.
+ */
+
+void __setup_cpu_power7(unsigned long offset, struct cpu_spec *t)
+{
+ if (!init_hvmode_206(t))
+ return;
+
+ mtspr(SPRN_LPID, 0);
+ mtspr(SPRN_PCR, PCR_MASK);
+ init_LPCR_ISA206(mfspr(SPRN_LPCR), LPCR_LPES1 >> LPCR_LPES_SH);
+}
+
+void __restore_cpu_power7(void)
+{
+ u64 msr;
+
+ msr = mfmsr();
+ if (!(msr & MSR_HV))
+ return;
+
+ mtspr(SPRN_LPID, 0);
+ mtspr(SPRN_PCR, PCR_MASK);
+ init_LPCR_ISA206(mfspr(SPRN_LPCR), LPCR_LPES1 >> LPCR_LPES_SH);
+}
+
+void __setup_cpu_power8(unsigned long offset, struct cpu_spec *t)
+{
+ init_FSCR();
+ init_PMU();
+ init_PMU_ISA207();
+
+ if (!init_hvmode_206(t))
+ return;
+
+ mtspr(SPRN_LPID, 0);
+ mtspr(SPRN_PCR, PCR_MASK);
+ init_LPCR_ISA206(mfspr(SPRN_LPCR) | LPCR_PECEDH, 0); /* LPES = 0 */
+ init_HFSCR();
+ init_PMU_HV();
+ init_PMU_HV_ISA207();
+}
+
+void __restore_cpu_power8(void)
+{
+ u64 msr;
+
+ init_FSCR();
+ init_PMU();
+ init_PMU_ISA207();
+
+ msr = mfmsr();
+ if (!(msr & MSR_HV))
+ return;
+
+ mtspr(SPRN_LPID, 0);
+ mtspr(SPRN_PCR, PCR_MASK);
+ init_LPCR_ISA206(mfspr(SPRN_LPCR) | LPCR_PECEDH, 0); /* LPES = 0 */
+ init_HFSCR();
+ init_PMU_HV();
+ init_PMU_HV_ISA207();
+}
+
+void __setup_cpu_power9(unsigned long offset, struct cpu_spec *t)
+{
+ init_FSCR_power9();
+ init_PMU();
+
+ if (!init_hvmode_206(t))
+ return;
+
+ mtspr(SPRN_PSSCR, 0);
+ mtspr(SPRN_LPID, 0);
+ mtspr(SPRN_PID, 0);
+ mtspr(SPRN_PCR, PCR_MASK);
+ init_LPCR_ISA300((mfspr(SPRN_LPCR) | LPCR_PECEDH | LPCR_PECE_HVEE |\
+ LPCR_HVICE | LPCR_HEIC) & ~(LPCR_UPRT | LPCR_HR), 0);
+ init_HFSCR();
+ init_PMU_HV();
+}
+
+void __restore_cpu_power9(void)
+{
+ u64 msr;
+
+ init_FSCR_power9();
+ init_PMU();
+
+ msr = mfmsr();
+ if (!(msr & MSR_HV))
+ return;
+
+ mtspr(SPRN_PSSCR, 0);
+ mtspr(SPRN_LPID, 0);
+ mtspr(SPRN_PID, 0);
+ mtspr(SPRN_PCR, PCR_MASK);
+ init_LPCR_ISA300((mfspr(SPRN_LPCR) | LPCR_PECEDH | LPCR_PECE_HVEE |\
+ LPCR_HVICE | LPCR_HEIC) & ~(LPCR_UPRT | LPCR_HR), 0);
+ init_HFSCR();
+ init_PMU_HV();
+}
+
+void __setup_cpu_power10(unsigned long offset, struct cpu_spec *t)
+{
+ init_FSCR_power10();
+ init_PMU();
+ init_PMU_ISA31();
+
+ if (!init_hvmode_206(t))
+ return;
+
+ mtspr(SPRN_PSSCR, 0);
+ mtspr(SPRN_LPID, 0);
+ mtspr(SPRN_PID, 0);
+ mtspr(SPRN_PCR, PCR_MASK);
+ init_LPCR_ISA300((mfspr(SPRN_LPCR) | LPCR_PECEDH | LPCR_PECE_HVEE |\
+ LPCR_HVICE | LPCR_HEIC) & ~(LPCR_UPRT | LPCR_HR), 0);
+ init_HFSCR();
+ init_PMU_HV();
+}
+
+void __restore_cpu_power10(void)
+{
+ u64 msr;
+
+ init_FSCR_power10();
+ init_PMU();
+ init_PMU_ISA31();
+
+ msr = mfmsr();
+ if (!(msr & MSR_HV))
+ return;
+
+ mtspr(SPRN_PSSCR, 0);
+ mtspr(SPRN_LPID, 0);
+ mtspr(SPRN_PID, 0);
+ mtspr(SPRN_PCR, PCR_MASK);
+ init_LPCR_ISA300((mfspr(SPRN_LPCR) | LPCR_PECEDH | LPCR_PECE_HVEE |\
+ LPCR_HVICE | LPCR_HEIC) & ~(LPCR_UPRT | LPCR_HR), 0);
+ init_HFSCR();
+ init_PMU_HV();
+}
diff --git a/arch/powerpc/kernel/cputable.c b/arch/powerpc/kernel/cputable.c
index 29de58d4dfb76..8fdb40ee86d11 100644
--- a/arch/powerpc/kernel/cputable.c
+++ b/arch/powerpc/kernel/cputable.c
@@ -60,19 +60,15 @@ extern void __setup_cpu_7410(unsigned long offset, struct cpu_spec* spec);
extern void __setup_cpu_745x(unsigned long offset, struct cpu_spec* spec);
#endif /* CONFIG_PPC32 */
#ifdef CONFIG_PPC64
+#include <asm/cpu_setup_power.h>
extern void __setup_cpu_ppc970(unsigned long offset, struct cpu_spec* spec);
extern void __setup_cpu_ppc970MP(unsigned long offset, struct cpu_spec* spec);
extern void __setup_cpu_pa6t(unsigned long offset, struct cpu_spec* spec);
extern void __restore_cpu_pa6t(void);
extern void __restore_cpu_ppc970(void);
-extern void __setup_cpu_power7(unsigned long offset, struct cpu_spec* spec);
-extern void __restore_cpu_power7(void);
-extern void __setup_cpu_power8(unsigned long offset, struct cpu_spec* spec);
-extern void __restore_cpu_power8(void);
-extern void __setup_cpu_power9(unsigned long offset, struct cpu_spec* spec);
-extern void __restore_cpu_power9(void);
-extern void __setup_cpu_power10(unsigned long offset, struct cpu_spec* spec);
-extern void __restore_cpu_power10(void);
+extern long __machine_check_early_realmode_p7(struct pt_regs *regs);
+extern long __machine_check_early_realmode_p8(struct pt_regs *regs);
+extern long __machine_check_early_realmode_p9(struct pt_regs *regs);
#endif /* CONFIG_PPC64 */
#if defined(CONFIG_E500)
extern void __setup_cpu_e5500(unsigned long offset, struct cpu_spec* spec);
--
2.34.1