From 61e2390ede3cea186cc01f5f3d0c9eb570c42c40 Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Mon, 5 Nov 2012 17:10:35 +1100 Subject: powerpc: Make load_hander handle upto 64k offset If we change load_hander() to use an ori instead of addi, we can load handlers upto 64k away provided we are still 64k aligned. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/exception-64s.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/powerpc/include/asm/exception-64s.h') diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h index a43c1473915f..9258daac4964 100644 --- a/arch/powerpc/include/asm/exception-64s.h +++ b/arch/powerpc/include/asm/exception-64s.h @@ -55,7 +55,8 @@ * word. */ #define LOAD_HANDLER(reg, label) \ - addi reg,reg,(label)-_stext; /* virt addr of handler ... */ + /* Handlers must be within 64K of kbase, which must be 64k aligned */ \ + ori reg,reg,(label)-_stext; /* virt addr of handler ... */ /* Exception register prefixes */ #define EXC_HV H -- cgit v1.2.3 From 4700dfaf1e988b785bd9791064df92d3353e8b88 Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Fri, 2 Nov 2012 17:21:28 +1100 Subject: powerpc: Add new macros needed for relocation on exceptions POWER8/v2.07 allows exceptions to be taken with the MMU still on. A new set of exception vectors is added at 0xc000_0000_0000_4xxx. When the HW takes us here, MSR IR/DR will be set already and we no longer need a costly RFID to turn the MMU back on again. The original 0x0 based exception vectors remain for when the HW can't leave the MMU on. Examples of this are when we can't trust the current the MMU mappings, like when we are changing from guest to hypervisor (HV 0 -> 1) or when the MMU was off already. In these cases the HW will take us to the original 0x0 based exception vectors with the MMU off as before. The below macros are copies of the macros used at the 0x0 offset but modified to handle the MMU being on. In these macros we use the link register to jump to the secondary handlers rather than using RFID (RFID was also use to turn on the MMU). Signed-off-by: Matt Evans Signed-off-by: Michael Neuling Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/exception-64s.h | 90 ++++++++++++++++++++++++++++++++ 1 file changed, 90 insertions(+) (limited to 'arch/powerpc/include/asm/exception-64s.h') diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h index 9258daac4964..10787d3673ac 100644 --- a/arch/powerpc/include/asm/exception-64s.h +++ b/arch/powerpc/include/asm/exception-64s.h @@ -48,6 +48,35 @@ #define EX_LR 72 #define EX_CFAR 80 +#ifdef CONFIG_RELOCATABLE +#define EXCEPTION_RELON_PROLOG_PSERIES_1(label, h) \ + ld r12,PACAKBASE(r13); /* get high part of &label */ \ + mfspr r11,SPRN_##h##SRR0; /* save SRR0 */ \ + LOAD_HANDLER(r12,label); \ + mtlr r12; \ + mfspr r12,SPRN_##h##SRR1; /* and SRR1 */ \ + li r10,MSR_RI; \ + mtmsrd r10,1; /* Set RI (EE=0) */ \ + blr; +#else +/* If not relocatable, we can jump directly -- and save messing with LR */ +#define EXCEPTION_RELON_PROLOG_PSERIES_1(label, h) \ + mfspr r11,SPRN_##h##SRR0; /* save SRR0 */ \ + mfspr r12,SPRN_##h##SRR1; /* and SRR1 */ \ + li r10,MSR_RI; \ + mtmsrd r10,1; /* Set RI (EE=0) */ \ + b label; +#endif + +/* + * As EXCEPTION_PROLOG_PSERIES(), except we've already got relocation on + * so no need to rfid. Save lr in case we're CONFIG_RELOCATABLE, in which + * case EXCEPTION_RELON_PROLOG_PSERIES_1 will be using lr. + */ +#define EXCEPTION_RELON_PROLOG_PSERIES(area, label, h, extra, vec) \ + EXCEPTION_PROLOG_1(area, extra, vec); \ + EXCEPTION_RELON_PROLOG_PSERIES_1(label, h) + /* * We're short on space and time in the exception prolog, so we can't * use the normal SET_REG_IMMEDIATE macro. Normally we just need the @@ -62,6 +91,22 @@ #define EXC_HV H #define EXC_STD +#if defined(CONFIG_RELOCATABLE) +/* + * If we support interrupts with relocation on AND we're a relocatable + * kernel, we need to use LR to get to the 2nd level handler. So, save/restore + * it when required. + */ +#define SAVE_LR(reg, area) mflr reg ; std reg,area+EX_LR(r13) +#define GET_LR(reg, area) ld reg,area+EX_LR(r13) +#define RESTORE_LR(reg, area) ld reg,area+EX_LR(r13) ; mtlr reg +#else +/* ...else LR is unused and in register. */ +#define SAVE_LR(reg, area) +#define GET_LR(reg, area) mflr reg +#define RESTORE_LR(reg, area) +#endif + #define __EXCEPTION_PROLOG_1(area, extra, vec) \ GET_PACA(r13); \ std r9,area+EX_R9(r13); /* save r9 - r12 */ \ @@ -233,6 +278,26 @@ label##_hv: \ EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common, \ EXC_HV, KVMTEST, vec) +#define STD_RELON_EXCEPTION_PSERIES(loc, vec, label) \ + . = loc; \ + .globl label##_relon_pSeries; \ +label##_relon_pSeries: \ + HMT_MEDIUM; \ + /* No guest interrupts come through here */ \ + SET_SCRATCH0(r13); /* save r13 */ \ + EXCEPTION_RELON_PROLOG_PSERIES(PACA_EXGEN, label##_common, \ + EXC_STD, KVMTEST_PR, vec) + +#define STD_RELON_EXCEPTION_HV(loc, vec, label) \ + . = loc; \ + .globl label##_relon_hv; \ +label##_relon_hv: \ + HMT_MEDIUM; \ + /* No guest interrupts come through here */ \ + SET_SCRATCH0(r13); /* save r13 */ \ + EXCEPTION_RELON_PROLOG_PSERIES(PACA_EXGEN, label##_common, \ + EXC_HV, KVMTEST, vec) + /* This associate vector numbers with bits in paca->irq_happened */ #define SOFTEN_VALUE_0x500 PACA_IRQ_EE #define SOFTEN_VALUE_0x502 PACA_IRQ_EE @@ -258,6 +323,9 @@ label##_hv: \ KVMTEST(vec); \ _SOFTEN_TEST(EXC_STD, vec) +#define SOFTEN_NOTEST_PR(vec) _SOFTEN_TEST(EXC_STD, vec) +#define SOFTEN_NOTEST_HV(vec) _SOFTEN_TEST(EXC_HV, vec) + #define __MASKABLE_EXCEPTION_PSERIES(vec, label, h, extra) \ HMT_MEDIUM; \ SET_SCRATCH0(r13); /* save r13 */ \ @@ -280,6 +348,28 @@ label##_hv: \ _MASKABLE_EXCEPTION_PSERIES(vec, label, \ EXC_HV, SOFTEN_TEST_HV) +#define __MASKABLE_RELON_EXCEPTION_PSERIES(vec, label, h, extra) \ + HMT_MEDIUM; \ + SET_SCRATCH0(r13); /* save r13 */ \ + __EXCEPTION_PROLOG_1(PACA_EXGEN, extra, vec); \ + EXCEPTION_RELON_PROLOG_PSERIES_1(label##_common, h); +#define _MASKABLE_RELON_EXCEPTION_PSERIES(vec, label, h, extra) \ + __MASKABLE_RELON_EXCEPTION_PSERIES(vec, label, h, extra) + +#define MASKABLE_RELON_EXCEPTION_PSERIES(loc, vec, label) \ + . = loc; \ + .globl label##_relon_pSeries; \ +label##_relon_pSeries: \ + _MASKABLE_RELON_EXCEPTION_PSERIES(vec, label, \ + EXC_STD, SOFTEN_NOTEST_PR) + +#define MASKABLE_RELON_EXCEPTION_HV(loc, vec, label) \ + . = loc; \ + .globl label##_relon_hv; \ +label##_relon_hv: \ + _MASKABLE_RELON_EXCEPTION_PSERIES(vec, label, \ + EXC_HV, SOFTEN_NOTEST_HV) + /* * Our exception common code can be passed various "additions" * to specify the behaviour of interrupts, whether to kick the -- cgit v1.2.3 From c1fb6816fb1b78dd94b673b0fdaa9a7a16e97bd1 Mon Sep 17 00:00:00 2001 From: Michael Neuling Date: Fri, 2 Nov 2012 17:21:43 +1100 Subject: powerpc: Add relocation on exception vector handlers POWER8/v2.07 allows exceptions to be taken with the MMU still on. A new set of exception vectors is added at 0xc000_0000_0000_4xxx. When the HW takes us here, MSR IR/DR will be set already and we no longer need a costly RFID to turn the MMU back on again. The original 0x0 based exception vectors remain for when the HW can't leave the MMU on. Examples of this are when we can't trust the current MMU mappings, like when we are changing from guest to hypervisor (HV 0 -> 1) or when the MMU was off already. In these cases the HW will take us to the original 0x0 based exception vectors with the MMU off as before. This uses the new macros added previously too implement these new execption vectors at 0xc000_0000_0000_4xxx. We exit these exception vectors using mflr/blr (rather than mtspr SSR0/RFID), since we don't need the costly MMU switch anymore. This moves the __end_interrupts marker down past these new 0x4000 vectors since they will need to be copied down to 0x0 when the kernel is not at 0x0. Signed-off-by: Matt Evans Signed-off-by: Michael Neuling Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/exception-64s.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'arch/powerpc/include/asm/exception-64s.h') diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h index 10787d3673ac..ad708dda3ba3 100644 --- a/arch/powerpc/include/asm/exception-64s.h +++ b/arch/powerpc/include/asm/exception-64s.h @@ -115,6 +115,7 @@ mfspr r10,SPRN_CFAR; \ std r10,area+EX_CFAR(r13); \ END_FTR_SECTION_NESTED(CPU_FTR_CFAR, CPU_FTR_CFAR, 66); \ + SAVE_LR(r10, area); \ mfcr r9; \ extra(vec); \ std r11,area+EX_R11(r13); \ @@ -215,6 +216,7 @@ do_kvm_##n: \ sth r1,PACA_TRAP_SAVE(r13); \ std r3,area+EX_R3(r13); \ addi r3,r13,area; /* r3 -> where regs are saved*/ \ + RESTORE_LR(r1, area); \ b bad_stack; \ 3: std r9,_CCR(r1); /* save CR in stackframe */ \ std r11,_NIP(r1); /* save SRR0 in stackframe */ \ @@ -240,8 +242,8 @@ do_kvm_##n: \ ld r10,area+EX_CFAR(r13); \ std r10,ORIG_GPR3(r1); \ END_FTR_SECTION_NESTED(CPU_FTR_CFAR, CPU_FTR_CFAR, 66); \ + GET_LR(r9,area); /* Get LR, later save to stack */ \ ld r2,PACATOC(r13); /* get kernel TOC into r2 */ \ - mflr r9; /* save LR in stackframe */ \ std r9,_LINK(r1); \ mfctr r10; /* save CTR in stackframe */ \ std r10,_CTR(r1); \ -- cgit v1.2.3