From 896a375623c3643a3f189353e7d4828c48a7fdf8 Mon Sep 17 00:00:00 2001 From: Grant Grundler Date: Fri, 21 Oct 2005 22:40:07 -0400 Subject: [PATCH] [PARISC] Make sure use of RFI conforms to PA 2.0 and 1.1 arch docs 2.6.12-rc4-pa3 : first pass at making sure use of RFI conforms to PA 2.0 arch pages F-4 and F-5, PA 1.1 Arch page 3-19 and 3-20. The discussion revolves around all the rules for clearing PSW Q-bit. The hard part is meeting all the rules for "relied upon translation". .align directive is used to guarantee the critical sequence ends more than 8 instructions (32 bytes) from the end of page. Signed-off-by: Grant Grundler Signed-off-by: Kyle McMartin --- arch/parisc/kernel/entry.S | 51 ++++++++--------- arch/parisc/kernel/head.S | 47 +++------------ arch/parisc/kernel/pacache.S | 105 +++++++++++++++++----------------- arch/parisc/kernel/real2.S | 18 ++---- include/asm-parisc/assembly.h | 25 ++++++++ include/asm-parisc/psw.h | 51 +++++++++-------- include/asm-parisc/tlbflush.h | 9 +-- 7 files changed, 146 insertions(+), 160 deletions(-) diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S index be0f07f2fa58..65a82c2645a7 100644 --- a/arch/parisc/kernel/entry.S +++ b/arch/parisc/kernel/entry.S @@ -30,9 +30,9 @@ * - save registers to kernel stack and handle in assembly or C */ +#include #include /* for LDREG/STREG defines */ #include -#include #include #include #include @@ -67,19 +67,22 @@ /* Switch to virtual mapping, trashing only %r1 */ .macro virt_map - rsm PSW_SM_Q,%r0 - tovirt_r1 %r29 - mfsp %sr7, %r1 - or,= %r0,%r1,%r0 /* Only save sr7 in sr3 if sr7 != 0 */ - mtsp %r1, %sr3 + /* pcxt_ssm_bug */ + rsm PSW_SM_I, %r0 /* barrier for "Relied upon Translation */ mtsp %r0, %sr4 mtsp %r0, %sr5 + mfsp %sr7, %r1 + or,= %r0,%r1,%r0 /* Only save sr7 in sr3 if sr7 != 0 */ + mtsp %r1, %sr3 + tovirt_r1 %r29 + load32 KERNEL_PSW, %r1 + + rsm PSW_SM_QUIET,%r0 /* second "heavy weight" ctl op */ mtsp %r0, %sr6 mtsp %r0, %sr7 - load32 KERNEL_PSW, %r1 - mtctl %r1, %cr22 mtctl %r0, %cr17 /* Clear IIASQ tail */ mtctl %r0, %cr17 /* Clear IIASQ head */ + mtctl %r1, %ipsw load32 4f, %r1 mtctl %r1, %cr18 /* Set IIAOQ tail */ ldo 4(%r1), %r1 @@ -888,9 +891,6 @@ _switch_to_ret: * this way, then we will need to copy %sr3 in to PT_SR[3..7], and * adjust IASQ[0..1]. * - * Note that the following code uses a "relied upon translation". - * See the parisc ACD for details. The ssm is necessary due to a - * PCXT bug. */ .align 4096 @@ -985,24 +985,19 @@ intr_restore: rest_fp %r1 rest_general %r29 - /* Create a "relied upon translation" PA 2.0 Arch. F-5 */ - ssm 0,%r0 - nop - nop - nop - nop - nop - nop - nop + /* inverse of virt_map */ + pcxt_ssm_bug + rsm PSW_SM_QUIET,%r0 /* prepare for rfi */ tophys_r1 %r29 - rsm (PSW_SM_Q|PSW_SM_P|PSW_SM_D|PSW_SM_I),%r0 /* Restore space id's and special cr's from PT_REGS - * structure pointed to by r29 */ + * structure pointed to by r29 + */ rest_specials %r29 - /* Important: Note that rest_stack restores r29 - * last (we are using it)! It also restores r1 and r30. */ + /* IMPORTANT: rest_stack restores r29 last (we are using it)! + * It also restores r1 and r30. + */ rest_stack rfi @@ -1153,15 +1148,17 @@ intr_save: CMPIB=,n 6,%r26,skip_save_ior - /* save_specials left ipsw value in r8 for us to test */ mfctl %cr20, %r16 /* isr */ + nop /* serialize mfctl on PA 2.0 to avoid 4 cycle penalty */ mfctl %cr21, %r17 /* ior */ + #ifdef __LP64__ /* * If the interrupted code was running with W bit off (32 bit), * clear the b bits (bits 0 & 1) in the ior. + * save_specials left ipsw value in r8 for us to test. */ extrd,u,*<> %r8,PSW_W_BIT,1,%r0 depdi 0,1,2,%r17 @@ -1487,10 +1484,10 @@ nadtlb_emulate: add,l %r1,%r24,%r1 /* doesn't affect c/b bits */ nadtlb_nullify: - mfctl %cr22,%r8 /* Get ipsw */ + mfctl %ipsw,%r8 ldil L%PSW_N,%r9 or %r8,%r9,%r8 /* Set PSW_N */ - mtctl %r8,%cr22 + mtctl %r8,%ipsw rfir nop diff --git a/arch/parisc/kernel/head.S b/arch/parisc/kernel/head.S index 28405edf8448..2b8738576ec2 100644 --- a/arch/parisc/kernel/head.S +++ b/arch/parisc/kernel/head.S @@ -224,8 +224,6 @@ stext_pdc_ret: mtctl %r0,%cr12 mtctl %r0,%cr13 - /* Prepare to RFI! Man all the cannons! */ - /* Initialize the global data pointer */ loadgp @@ -254,46 +252,16 @@ $is_pa20: $install_iva: mtctl %r10,%cr14 -#ifdef __LP64__ - b aligned_rfi + b aligned_rfi /* Prepare to RFI! Man all the cannons! */ nop - .align 256 + .align 128 aligned_rfi: - ssm 0,0 - nop /* 1 */ - nop /* 2 */ - nop /* 3 */ - nop /* 4 */ - nop /* 5 */ - nop /* 6 */ - nop /* 7 */ - nop /* 8 */ -#endif - -#ifdef __LP64__ /* move to psw.h? */ -#define PSW_BITS PSW_Q+PSW_I+PSW_D+PSW_P+PSW_R -#else -#define PSW_BITS PSW_SM_Q -#endif - -$rfi: - /* turn off troublesome PSW bits */ - rsm PSW_BITS,%r0 + pcxt_ssm_bug - /* kernel PSW: - * - no interruptions except HPMC and TOC (which are handled by PDC) - * - Q bit set (IODC / PDC interruptions) - * - big-endian - * - virtually mapped - */ - load32 KERNEL_PSW,%r10 - mtctl %r10,%ipsw + rsm PSW_SM_QUIET,%r0 /* off troublesome PSW bits */ + /* Don't need NOPs, have 8 compliant insn before rfi */ - /* Set the space pointers for the post-RFI world - ** Clear the two-level IIA Space Queue, effectively setting - ** Kernel space. - */ mtctl %r0,%cr17 /* Clear IIASQ tail */ mtctl %r0,%cr17 /* Clear IIASQ head */ @@ -301,8 +269,11 @@ $rfi: mtctl %r11,%cr18 /* IIAOQ head */ ldo 4(%r11),%r11 mtctl %r11,%cr18 /* IIAOQ tail */ + + load32 KERNEL_PSW,%r10 + mtctl %r10,%ipsw - /* Jump to hyperspace */ + /* Jump through hyperspace to Virt Mode */ rfi nop diff --git a/arch/parisc/kernel/pacache.S b/arch/parisc/kernel/pacache.S index 77e03bc0f935..71ade44c4618 100644 --- a/arch/parisc/kernel/pacache.S +++ b/arch/parisc/kernel/pacache.S @@ -40,8 +40,8 @@ .level 2.0 #endif -#include #include +#include #include #include @@ -62,32 +62,23 @@ flush_tlb_all_local: * to happen in real mode with all interruptions disabled. */ - /* - * Once again, we do the rfi dance ... some day we need examine - * all of our uses of this type of code and see what can be - * consolidated. - */ - - rsm PSW_SM_I, %r19 /* relied upon translation! PA 2.0 Arch. F-5 */ + /* pcxt_ssm_bug - relied upon translation! PA 2.0 Arch. F-4 and F-5 */ + rsm PSW_SM_I, %r19 /* save I-bit state */ + load32 PA(1f), %r1 nop nop nop nop nop - nop - nop - - rsm PSW_SM_Q, %r0 /* Turn off Q bit to load iia queue */ - ldil L%REAL_MODE_PSW, %r1 - ldo R%REAL_MODE_PSW(%r1), %r1 - mtctl %r1, %cr22 + + rsm PSW_SM_Q, %r0 /* prep to load iia queue */ mtctl %r0, %cr17 /* Clear IIASQ tail */ mtctl %r0, %cr17 /* Clear IIASQ head */ - ldil L%PA(1f), %r1 - ldo R%PA(1f)(%r1), %r1 mtctl %r1, %cr18 /* IIAOQ head */ ldo 4(%r1), %r1 mtctl %r1, %cr18 /* IIAOQ tail */ + load32 REAL_MODE_PSW, %r1 + mtctl %r1, %ipsw rfi nop @@ -178,29 +169,36 @@ fdtonemiddle: /* Loop if LOOP = 1 */ ADDIB> -1, %r22, fdtoneloop /* Outer loop count decr */ add %r21, %r20, %r20 /* increment space */ -fdtdone: - /* Switch back to virtual mode */ +fdtdone: + /* + * Switch back to virtual mode + */ + /* pcxt_ssm_bug */ + rsm PSW_SM_I, %r0 + load32 2f, %r1 + nop + nop + nop + nop + nop - rsm PSW_SM_Q, %r0 /* clear Q bit to load iia queue */ - ldil L%KERNEL_PSW, %r1 - ldo R%KERNEL_PSW(%r1), %r1 - or %r1, %r19, %r1 /* Set I bit if set on entry */ - mtctl %r1, %cr22 + rsm PSW_SM_Q, %r0 /* prep to load iia queue */ mtctl %r0, %cr17 /* Clear IIASQ tail */ mtctl %r0, %cr17 /* Clear IIASQ head */ - ldil L%(2f), %r1 - ldo R%(2f)(%r1), %r1 mtctl %r1, %cr18 /* IIAOQ head */ ldo 4(%r1), %r1 mtctl %r1, %cr18 /* IIAOQ tail */ + load32 KERNEL_PSW, %r1 + or %r1, %r19, %r1 /* I-bit to state on entry */ + mtctl %r1, %ipsw /* restore I-bit (entire PSW) */ rfi nop 2: bv %r0(%r2) nop - .exit + .exit .procend .export flush_instruction_cache_local,code @@ -238,7 +236,7 @@ fioneloop: /* Loop if LOOP = 1 */ fisync: sync - mtsm %r22 + mtsm %r22 /* restore I-bit */ bv %r0(%r2) nop .exit @@ -281,7 +279,7 @@ fdoneloop: /* Loop if LOOP = 1 */ fdsync: syncdma sync - mtsm %r22 + mtsm %r22 /* restore I-bit */ bv %r0(%r2) nop .exit @@ -988,11 +986,12 @@ flush_kernel_icache_range_asm: bv %r0(%r2) nop .exit - .procend - .align 128 - + /* align should cover use of rfi in disable_sr_hashing_asm and + * srdis_done. + */ + .align 256 .export disable_sr_hashing_asm,code disable_sr_hashing_asm: @@ -1000,28 +999,26 @@ disable_sr_hashing_asm: .callinfo NO_CALLS .entry - /* Switch to real mode */ - - ssm 0, %r0 /* relied upon translation! */ - nop - nop + /* + * Switch to real mode + */ + /* pcxt_ssm_bug */ + rsm PSW_SM_I, %r0 + load32 PA(1f), %r1 nop nop nop nop nop - - rsm (PSW_SM_Q|PSW_SM_I), %r0 /* disable Q&I to load the iia queue */ - ldil L%REAL_MODE_PSW, %r1 - ldo R%REAL_MODE_PSW(%r1), %r1 - mtctl %r1, %cr22 + + rsm PSW_SM_Q, %r0 /* prep to load iia queue */ mtctl %r0, %cr17 /* Clear IIASQ tail */ mtctl %r0, %cr17 /* Clear IIASQ head */ - ldil L%PA(1f), %r1 - ldo R%PA(1f)(%r1), %r1 mtctl %r1, %cr18 /* IIAOQ head */ ldo 4(%r1), %r1 mtctl %r1, %cr18 /* IIAOQ tail */ + load32 REAL_MODE_PSW, %r1 + mtctl %r1, %ipsw rfi nop @@ -1053,27 +1050,31 @@ srdis_pcxl: srdis_pa20: - /* Disable Space Register Hashing for PCXU,PCXU+,PCXW,PCXW+ */ + /* Disable Space Register Hashing for PCXU,PCXU+,PCXW,PCXW+,PCXW2 */ .word 0x144008bc /* mfdiag %dr2, %r28 */ depdi 0, 54,1, %r28 /* clear DIAG_SPHASH_ENAB (bit 54) */ .word 0x145c1840 /* mtdiag %r28, %dr2 */ -srdis_done: +srdis_done: /* Switch back to virtual mode */ + rsm PSW_SM_I, %r0 /* prep to load iia queue */ + load32 2f, %r1 + nop + nop + nop + nop + nop - rsm PSW_SM_Q, %r0 /* clear Q bit to load iia queue */ - ldil L%KERNEL_PSW, %r1 - ldo R%KERNEL_PSW(%r1), %r1 - mtctl %r1, %cr22 + rsm PSW_SM_Q, %r0 /* prep to load iia queue */ mtctl %r0, %cr17 /* Clear IIASQ tail */ mtctl %r0, %cr17 /* Clear IIASQ head */ - ldil L%(2f), %r1 - ldo R%(2f)(%r1), %r1 mtctl %r1, %cr18 /* IIAOQ head */ ldo 4(%r1), %r1 mtctl %r1, %cr18 /* IIAOQ tail */ + load32 KERNEL_PSW, %r1 + mtctl %r1, %ipsw rfi nop diff --git a/arch/parisc/kernel/real2.S b/arch/parisc/kernel/real2.S index 8dd5defb7316..2310fc1b06a9 100644 --- a/arch/parisc/kernel/real2.S +++ b/arch/parisc/kernel/real2.S @@ -7,8 +7,8 @@ * Copyright (C) 2000 Hewlett Packard (Paul Bame bame@puffin.external.hp.com) * */ -#include #include +#include .section .bss .export real_stack @@ -147,20 +147,17 @@ restore_control_regs: .text rfi_virt2real: /* switch to real mode... */ - ssm 0,0 /* See "relied upon translation" */ - nop /* PA 2.0 Arch. F-5 */ - nop - nop + rsm PSW_SM_I,%r0 + load32 PA(rfi_v2r_1), %r1 nop nop nop nop nop - rsm (PSW_SM_Q|PSW_SM_I),%r0 /* disable Q & I bits to load iia queue */ + rsm PSW_SM_Q,%r0 /* disable Q & I bits to load iia queue */ mtctl %r0, %cr17 /* Clear IIASQ tail */ mtctl %r0, %cr17 /* Clear IIASQ head */ - load32 PA(rfi_v2r_1), %r1 mtctl %r1, %cr18 /* IIAOQ head */ ldo 4(%r1), %r1 mtctl %r1, %cr18 /* IIAOQ tail */ @@ -184,10 +181,8 @@ rfi_v2r_1: .text .align 128 rfi_real2virt: - ssm 0,0 /* See "relied upon translation" */ - nop /* PA 2.0 Arch. F-5 */ - nop - nop + rsm PSW_SM_I,%r0 + load32 (rfi_r2v_1), %r1 nop nop nop @@ -197,7 +192,6 @@ rfi_real2virt: rsm PSW_SM_Q,%r0 /* disable Q bit to load iia queue */ mtctl %r0, %cr17 /* Clear IIASQ tail */ mtctl %r0, %cr17 /* Clear IIASQ head */ - load32 (rfi_r2v_1), %r1 mtctl %r1, %cr18 /* IIAOQ head */ ldo 4(%r1), %r1 mtctl %r1, %cr18 /* IIAOQ tail */ diff --git a/include/asm-parisc/assembly.h b/include/asm-parisc/assembly.h index 30b023411fef..b24a99e3ef9c 100644 --- a/include/asm-parisc/assembly.h +++ b/include/asm-parisc/assembly.h @@ -450,5 +450,30 @@ REST_CR (%cr22, PT_PSW (\regs)) .endm + + /* First step to create a "relied upon translation" + * See PA 2.0 Arch. page F-4 and F-5. + * + * The ssm was originally necessary due to a "PCxT bug". + * But someone decided it needed to be added to the architecture + * and this "feature" went into rev3 of PA-RISC 1.1 Arch Manual. + * It's been carried forward into PA 2.0 Arch as well. :^( + * + * "ssm 0,%r0" is a NOP with side effects (prefetch barrier). + * rsm/ssm prevents the ifetch unit from speculatively fetching + * instructions past this line in the code stream. + * PA 2.0 processor will single step all insn in the same QUAD (4 insn). + */ + .macro pcxt_ssm_bug + rsm PSW_SM_I,%r0 + nop /* 1 */ + nop /* 2 */ + nop /* 3 */ + nop /* 4 */ + nop /* 5 */ + nop /* 6 */ + nop /* 7 */ + .endm + #endif /* __ASSEMBLY__ */ #endif diff --git a/include/asm-parisc/psw.h b/include/asm-parisc/psw.h index 51323029f377..4334d6ca2add 100644 --- a/include/asm-parisc/psw.h +++ b/include/asm-parisc/psw.h @@ -1,4 +1,7 @@ #ifndef _PARISC_PSW_H + +#include + #define PSW_I 0x00000001 #define PSW_D 0x00000002 #define PSW_P 0x00000004 @@ -9,6 +12,16 @@ #define PSW_G 0x00000040 /* PA1.x only */ #define PSW_O 0x00000080 /* PA2.0 only */ +/* ssm/rsm instructions number PSW_W and PSW_E differently */ +#define PSW_SM_I PSW_I /* Enable External Interrupts */ +#define PSW_SM_D PSW_D +#define PSW_SM_P PSW_P +#define PSW_SM_Q PSW_Q /* Enable Interrupt State Collection */ +#define PSW_SM_R PSW_R /* Enable Recover Counter Trap */ +#define PSW_SM_W 0x200 /* PA2.0 only : Enable Wide Mode */ + +#define PSW_SM_QUIET PSW_SM_R+PSW_SM_Q+PSW_SM_P+PSW_SM_D+PSW_SM_I + #define PSW_CB 0x0000ff00 #define PSW_M 0x00010000 @@ -30,33 +43,21 @@ #define PSW_Z 0x40000000 /* PA1.x only */ #define PSW_Y 0x80000000 /* PA1.x only */ -#ifdef __LP64__ -#define PSW_HI_CB 0x000000ff /* PA2.0 only */ +#ifdef CONFIG_64BIT +# define PSW_HI_CB 0x000000ff /* PA2.0 only */ #endif -/* PSW bits to be used with ssm/rsm */ -#define PSW_SM_I 0x1 -#define PSW_SM_D 0x2 -#define PSW_SM_P 0x4 -#define PSW_SM_Q 0x8 -#define PSW_SM_R 0x10 -#define PSW_SM_F 0x20 -#define PSW_SM_G 0x40 -#define PSW_SM_O 0x80 -#define PSW_SM_E 0x100 -#define PSW_SM_W 0x200 - -#ifdef __LP64__ -# define USER_PSW (PSW_C | PSW_Q | PSW_P | PSW_D | PSW_I) -# define KERNEL_PSW (PSW_W | PSW_C | PSW_Q | PSW_P | PSW_D) -# define REAL_MODE_PSW (PSW_W | PSW_Q) -# define USER_PSW_MASK (PSW_W | PSW_T | PSW_N | PSW_X | PSW_B | PSW_V | PSW_CB) -# define USER_PSW_HI_MASK (PSW_HI_CB) -#else -# define USER_PSW (PSW_C | PSW_Q | PSW_P | PSW_D | PSW_I) -# define KERNEL_PSW (PSW_C | PSW_Q | PSW_P | PSW_D) -# define REAL_MODE_PSW (PSW_Q) -# define USER_PSW_MASK (PSW_T | PSW_N | PSW_X | PSW_B | PSW_V | PSW_CB) +#ifdef CONFIG_64BIT +# define USER_PSW_HI_MASK PSW_HI_CB +# define WIDE_PSW PSW_W +#else +# define WIDE_PSW 0 #endif +/* Used when setting up for rfi */ +#define KERNEL_PSW (WIDE_PSW | PSW_C | PSW_Q | PSW_P | PSW_D) +#define REAL_MODE_PSW (WIDE_PSW | PSW_Q) +#define USER_PSW_MASK (WIDE_PSW | PSW_T | PSW_N | PSW_X | PSW_B | PSW_V | PSW_CB) +#define USER_PSW (PSW_C | PSW_Q | PSW_P | PSW_D | PSW_I) + #endif diff --git a/include/asm-parisc/tlbflush.h b/include/asm-parisc/tlbflush.h index eb27b78930e8..efbb2d8625b1 100644 --- a/include/asm-parisc/tlbflush.h +++ b/include/asm-parisc/tlbflush.h @@ -64,29 +64,26 @@ static inline void flush_tlb_range(struct vm_area_struct *vma, { unsigned long npages; - npages = ((end - (start & PAGE_MASK)) + (PAGE_SIZE - 1)) >> PAGE_SHIFT; - if (npages >= 512) /* XXX arbitrary, should be tuned */ + if (npages >= 512) /* 2MB of space: arbitrary, should be tuned */ flush_tlb_all(); else { mtsp(vma->vm_mm->context,1); + purge_tlb_start(); if (split_tlb) { - purge_tlb_start(); while (npages--) { pdtlb(start); pitlb(start); start += PAGE_SIZE; } - purge_tlb_end(); } else { - purge_tlb_start(); while (npages--) { pdtlb(start); start += PAGE_SIZE; } - purge_tlb_end(); } + purge_tlb_end(); } } -- 2.39.5