From: Michal Simek Date: Tue, 26 May 2009 14:30:18 +0000 (+0200) Subject: microblaze_mmu_v2: Update process creation for MMU X-Git-Tag: firefly_0821_release~13950^2~20 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=5233806dfe6f88fb1a01db3729eeda78f65bcbd1;p=firefly-linux-kernel-4.4.55.git microblaze_mmu_v2: Update process creation for MMU Signed-off-by: Michal Simek --- diff --git a/arch/microblaze/include/asm/processor.h b/arch/microblaze/include/asm/processor.h index 9329029d2614..563c6b9453f0 100644 --- a/arch/microblaze/include/asm/processor.h +++ b/arch/microblaze/include/asm/processor.h @@ -1,6 +1,6 @@ /* - * Copyright (C) 2008 Michal Simek - * Copyright (C) 2008 PetaLogix + * Copyright (C) 2008-2009 Michal Simek + * Copyright (C) 2008-2009 PetaLogix * Copyright (C) 2006 Atmark Techno, Inc. * * This file is subject to the terms and conditions of the GNU General Public @@ -26,14 +26,15 @@ extern const struct seq_operations cpuinfo_op; # define cpu_sleep() do {} while (0) # define prepare_to_copy(tsk) do {} while (0) -# endif /* __ASSEMBLY__ */ - #define task_pt_regs(tsk) \ (((struct pt_regs *)(THREAD_SIZE + task_stack_page(tsk))) - 1) /* Do necessary setup to start up a newly executed thread. */ void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp); +# endif /* __ASSEMBLY__ */ + +# ifndef CONFIG_MMU /* * User space process size: memory size * @@ -85,4 +86,90 @@ extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); # define KSTK_EIP(tsk) (0) # define KSTK_ESP(tsk) (0) +# else /* CONFIG_MMU */ + +/* + * This is used to define STACK_TOP, and with MMU it must be below + * kernel base to select the correct PGD when handling MMU exceptions. + */ +# define TASK_SIZE (CONFIG_KERNEL_START) + +/* + * This decides where the kernel will search for a free chunk of vm + * space during mmap's. + */ +# define TASK_UNMAPPED_BASE (TASK_SIZE / 8 * 3) + +# define THREAD_KSP 0 + +# ifndef __ASSEMBLY__ + +/* + * Default implementation of macro that returns current + * instruction pointer ("program counter"). + */ +# define current_text_addr() ({ __label__ _l; _l: &&_l; }) + +/* If you change this, you must change the associated assembly-languages + * constants defined below, THREAD_*. + */ +struct thread_struct { + /* kernel stack pointer (must be first field in structure) */ + unsigned long ksp; + unsigned long ksp_limit; /* if ksp <= ksp_limit stack overflow */ + void *pgdir; /* root of page-table tree */ + struct pt_regs *regs; /* Pointer to saved register state */ +}; + +# define INIT_THREAD { \ + .ksp = sizeof init_stack + (unsigned long)init_stack, \ + .pgdir = swapper_pg_dir, \ +} + +/* Do necessary setup to start up a newly executed thread. */ +void start_thread(struct pt_regs *regs, + unsigned long pc, unsigned long usp); + +/* Free all resources held by a thread. */ +extern inline void release_thread(struct task_struct *dead_task) +{ +} + +extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); + +/* Free current thread data structures etc. */ +static inline void exit_thread(void) +{ +} + +/* Return saved (kernel) PC of a blocked thread. */ +# define thread_saved_pc(tsk) \ + ((tsk)->thread.regs ? (tsk)->thread.regs->r15 : 0) + +unsigned long get_wchan(struct task_struct *p); + +/* The size allocated for kernel stacks. This _must_ be a power of two! */ +# define KERNEL_STACK_SIZE 0x2000 + +/* Return some info about the user process TASK. */ +# define task_tos(task) ((unsigned long)(task) + KERNEL_STACK_SIZE) +# define task_regs(task) ((struct pt_regs *)task_tos(task) - 1) + +# define task_pt_regs_plus_args(tsk) \ + (((void *)task_pt_regs(tsk)) - STATE_SAVE_ARG_SPACE) + +# define task_sp(task) (task_regs(task)->r1) +# define task_pc(task) (task_regs(task)->pc) +/* Grotty old names for some. */ +# define KSTK_EIP(task) (task_pc(task)) +# define KSTK_ESP(task) (task_sp(task)) + +/* FIXME */ +# define deactivate_mm(tsk, mm) do { } while (0) + +# define STACK_TOP TASK_SIZE +# define STACK_TOP_MAX STACK_TOP + +# endif /* __ASSEMBLY__ */ +# endif /* CONFIG_MMU */ #endif /* _ASM_MICROBLAZE_PROCESSOR_H */ diff --git a/arch/microblaze/include/asm/registers.h b/arch/microblaze/include/asm/registers.h index 834142d9356f..68c3afb73877 100644 --- a/arch/microblaze/include/asm/registers.h +++ b/arch/microblaze/include/asm/registers.h @@ -1,6 +1,6 @@ /* - * Copyright (C) 2008 Michal Simek - * Copyright (C) 2008 PetaLogix + * Copyright (C) 2008-2009 Michal Simek + * Copyright (C) 2008-2009 PetaLogix * Copyright (C) 2006 Atmark Techno, Inc. * * This file is subject to the terms and conditions of the GNU General Public @@ -30,4 +30,21 @@ #define FSR_UF (1<<1) /* Underflow */ #define FSR_DO (1<<0) /* Denormalized operand error */ +# ifdef CONFIG_MMU +/* Machine State Register (MSR) Fields */ +# define MSR_UM (1<<11) /* User Mode */ +# define MSR_UMS (1<<12) /* User Mode Save */ +# define MSR_VM (1<<13) /* Virtual Mode */ +# define MSR_VMS (1<<14) /* Virtual Mode Save */ + +# define MSR_KERNEL (MSR_EE | MSR_VM) +/* # define MSR_USER (MSR_KERNEL | MSR_UM | MSR_IE) */ +# define MSR_KERNEL_VMS (MSR_EE | MSR_VMS) +/* # define MSR_USER_VMS (MSR_KERNEL_VMS | MSR_UMS | MSR_IE) */ + +/* Exception State Register (ESR) Fields */ +# define ESR_DIZ (1<<11) /* Zone Protection */ +# define ESR_S (1<<10) /* Store instruction */ + +# endif /* CONFIG_MMU */ #endif /* _ASM_MICROBLAZE_REGISTERS_H */ diff --git a/arch/microblaze/include/asm/segment.h b/arch/microblaze/include/asm/segment.h index 7f5dcc56eea1..0e7102c3fb11 100644 --- a/arch/microblaze/include/asm/segment.h +++ b/arch/microblaze/include/asm/segment.h @@ -1,6 +1,6 @@ /* - * Copyright (C) 2008 Michal Simek - * Copyright (C) 2008 PetaLogix + * Copyright (C) 2008-2009 Michal Simek + * Copyright (C) 2008-2009 PetaLogix * Copyright (C) 2006 Atmark Techno, Inc. * * This file is subject to the terms and conditions of the GNU General Public @@ -11,7 +11,7 @@ #ifndef _ASM_MICROBLAZE_SEGMENT_H #define _ASM_MICROBLAZE_SEGMENT_H -#ifndef __ASSEMBLY__ +# ifndef __ASSEMBLY__ typedef struct { unsigned long seg; @@ -29,15 +29,21 @@ typedef struct { * * For non-MMU arch like Microblaze, KERNEL_DS and USER_DS is equal. */ -# define KERNEL_DS ((mm_segment_t){0}) +# define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) + +# ifndef CONFIG_MMU +# define KERNEL_DS MAKE_MM_SEG(0) # define USER_DS KERNEL_DS +# else +# define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF) +# define USER_DS MAKE_MM_SEG(TASK_SIZE - 1) +# endif # define get_ds() (KERNEL_DS) # define get_fs() (current_thread_info()->addr_limit) -# define set_fs(x) \ - do { current_thread_info()->addr_limit = (x); } while (0) +# define set_fs(val) (current_thread_info()->addr_limit = (val)) -# define segment_eq(a, b) ((a).seg == (b).seg) +# define segment_eq(a, b) ((a).seg == (b).seg) # endif /* __ASSEMBLY__ */ #endif /* _ASM_MICROBLAZE_SEGMENT_H */ diff --git a/arch/microblaze/kernel/process.c b/arch/microblaze/kernel/process.c index 685ad71ced50..00b12c6d5326 100644 --- a/arch/microblaze/kernel/process.c +++ b/arch/microblaze/kernel/process.c @@ -126,9 +126,54 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, else childregs->r1 = ((unsigned long) ti) + THREAD_SIZE; +#ifndef CONFIG_MMU memset(&ti->cpu_context, 0, sizeof(struct cpu_context)); ti->cpu_context.r1 = (unsigned long)childregs; ti->cpu_context.msr = (unsigned long)childregs->msr; +#else + + /* if creating a kernel thread then update the current reg (we don't + * want to use the parent's value when restoring by POP_STATE) */ + if (kernel_mode(regs)) + /* save new current on stack to use POP_STATE */ + childregs->CURRENT_TASK = (unsigned long)p; + /* if returning to user then use the parent's value of this register */ + + /* if we're creating a new kernel thread then just zeroing all + * the registers. That's OK for a brand new thread.*/ + /* Pls. note that some of them will be restored in POP_STATE */ + if (kernel_mode(regs)) + memset(&ti->cpu_context, 0, sizeof(struct cpu_context)); + /* if this thread is created for fork/vfork/clone, then we want to + * restore all the parent's context */ + /* in addition to the registers which will be restored by POP_STATE */ + else { + ti->cpu_context = *(struct cpu_context *)regs; + childregs->msr |= MSR_UMS; + } + + /* FIXME STATE_SAVE_PT_OFFSET; */ + ti->cpu_context.r1 = (unsigned long)childregs - STATE_SAVE_ARG_SPACE; + /* we should consider the fact that childregs is a copy of the parent + * regs which were saved immediately after entering the kernel state + * before enabling VM. This MSR will be restored in switch_to and + * RETURN() and we want to have the right machine state there + * specifically this state must have INTs disabled before and enabled + * after performing rtbd + * compose the right MSR for RETURN(). It will work for switch_to also + * excepting for VM and UMS + * don't touch UMS , CARRY and cache bits + * right now MSR is a copy of parent one */ + childregs->msr |= MSR_BIP; + childregs->msr &= ~MSR_EIP; + childregs->msr |= MSR_IE; + childregs->msr &= ~MSR_VM; + childregs->msr |= MSR_VMS; + childregs->msr |= MSR_EE; /* exceptions will be enabled*/ + + ti->cpu_context.msr = (childregs->msr|MSR_VM); + ti->cpu_context.msr &= ~MSR_UMS; /* switch_to to kernel mode */ +#endif ti->cpu_context.r15 = (unsigned long)ret_from_fork - 8; if (clone_flags & CLONE_SETTLS) @@ -137,6 +182,7 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, return 0; } +#ifndef CONFIG_MMU /* * Return saved PC of a blocked thread. */ @@ -151,6 +197,7 @@ unsigned long thread_saved_pc(struct task_struct *tsk) else return ctx->r14; } +#endif static void kernel_thread_helper(int (*fn)(void *), void *arg) { @@ -189,3 +236,14 @@ void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp) regs->r1 = usp; regs->pt_mode = 0; } + +#ifdef CONFIG_MMU +#include +/* + * Set up a thread for executing a new program + */ +int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpregs) +{ + return 0; /* MicroBlaze has no separate FPU registers */ +} +#endif /* CONFIG_MMU */