arm64: CPU support

/*

 * arch/arm64/include/asm/cputable.h

 *

 * Copyright (C) 2012 ARM Ltd.

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

#ifndef __ASM_CPUTABLE_H

#define __ASM_CPUTABLE_H

struct cpu_info {

	unsigned int	cpu_id_val;

	unsigned int	cpu_id_mask;

	const char	*cpu_name;

	unsigned long	(*cpu_setup)(void);

};

extern struct cpu_info *lookup_processor_type(unsigned int);

#endif

/*

 * Copyright (C) 2012 ARM Ltd.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

#ifndef __ASM_CPUTYPE_H

#define __ASM_CPUTYPE_H

#define ID_MIDR_EL1		"midr_el1"

#define ID_CTR_EL0		"ctr_el0"

#define ID_AA64PFR0_EL1		"id_aa64pfr0_el1"

#define ID_AA64DFR0_EL1		"id_aa64dfr0_el1"

#define ID_AA64AFR0_EL1		"id_aa64afr0_el1"

#define ID_AA64ISAR0_EL1	"id_aa64isar0_el1"

#define ID_AA64MMFR0_EL1	"id_aa64mmfr0_el1"

#define read_cpuid(reg) ({						\

	u64 __val;							\

	asm("mrs	%0, " reg : "=r" (__val));			\

	__val;								\

})

/*

 * The CPU ID never changes at run time, so we might as well tell the

 * compiler that it's constant.  Use this function to read the CPU ID

 * rather than directly reading processor_id or read_cpuid() directly.

 */

static inline u32 __attribute_const__ read_cpuid_id(void)

{

	return read_cpuid(ID_MIDR_EL1);

}

static inline u32 __attribute_const__ read_cpuid_cachetype(void)

{

	return read_cpuid(ID_CTR_EL0);

}

#endif

/*

 * Based on arch/arm/include/asm/proc-fns.h

 *

 * Copyright (C) 1997-1999 Russell King

 * Copyright (C) 2000 Deep Blue Solutions Ltd

 * Copyright (C) 2012 ARM Ltd.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

#ifndef __ASM_PROCFNS_H

#define __ASM_PROCFNS_H

#ifdef __KERNEL__

#ifndef __ASSEMBLY__

#include <asm/page.h>

struct mm_struct;

extern void cpu_cache_off(void);

extern void cpu_do_idle(void);

extern void cpu_do_switch_mm(unsigned long pgd_phys, struct mm_struct *mm);

extern void cpu_reset(unsigned long addr) __attribute__((noreturn));

#include <asm/memory.h>

#define cpu_switch_mm(pgd,mm) cpu_do_switch_mm(virt_to_phys(pgd),mm)

#define cpu_get_pgd()					\

({							\

	unsigned long pg;				\

	asm("mrs	%0, ttbr0_el1\n"		\

	    : "=r" (pg));				\

	pg &= ~0xffff000000003ffful;			\

	(pgd_t *)phys_to_virt(pg);			\

})

#endif /* __ASSEMBLY__ */

#endif /* __KERNEL__ */

#endif /* __ASM_PROCFNS_H */

/*

 * Based on arch/arm/include/asm/processor.h

 *

 * Copyright (C) 1995-1999 Russell King

 * Copyright (C) 2012 ARM Ltd.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

#ifndef __ASM_PROCESSOR_H

#define __ASM_PROCESSOR_H

/*

 * Default implementation of macro that returns current

 * instruction pointer ("program counter").

 */

#define current_text_addr() ({ __label__ _l; _l: &&_l;})

#ifdef __KERNEL__

#include <linux/string.h>

#include <asm/fpsimd.h>

#include <asm/hw_breakpoint.h>

#include <asm/ptrace.h>

#include <asm/types.h>

#ifdef __KERNEL__

#define STACK_TOP_MAX		TASK_SIZE_64

#ifdef CONFIG_COMPAT

#define AARCH32_VECTORS_BASE	0xffff0000

#define STACK_TOP		(test_thread_flag(TIF_32BIT) ? \

				AARCH32_VECTORS_BASE : STACK_TOP_MAX)

#else

#define STACK_TOP		STACK_TOP_MAX

#endif /* CONFIG_COMPAT */

#endif /* __KERNEL__ */

struct debug_info {

	/* Have we suspended stepping by a debugger? */

	int			suspended_step;

	/* Allow breakpoints and watchpoints to be disabled for this thread. */

	int			bps_disabled;

	int			wps_disabled;

	/* Hardware breakpoints pinned to this task. */

	struct perf_event	*hbp_break[ARM_MAX_BRP];

	struct perf_event	*hbp_watch[ARM_MAX_WRP];

};

struct cpu_context {

	unsigned long x19;

	unsigned long x20;

	unsigned long x21;

	unsigned long x22;

	unsigned long x23;

	unsigned long x24;

	unsigned long x25;

	unsigned long x26;

	unsigned long x27;

	unsigned long x28;

	unsigned long fp;

	unsigned long sp;

	unsigned long pc;

};

struct thread_struct {

	struct cpu_context	cpu_context;	/* cpu context */

	unsigned long		tp_value;

	struct fpsimd_state	fpsimd_state;

	unsigned long		fault_address;	/* fault info */

	struct debug_info	debug;		/* debugging */

};

#define INIT_THREAD  {	}

static inline void start_thread_common(struct pt_regs *regs, unsigned long pc)

{

	memset(regs, 0, sizeof(*regs));

	regs->syscallno = ~0UL;

	regs->pc = pc;

}

static inline void start_thread(struct pt_regs *regs, unsigned long pc,

				unsigned long sp)

{

	unsigned long *stack = (unsigned long *)sp;

	start_thread_common(regs, pc);

	regs->pstate = PSR_MODE_EL0t;

	regs->sp = sp;

	regs->regs[2] = stack[2];	/* x2 (envp) */

	regs->regs[1] = stack[1];	/* x1 (argv) */

	regs->regs[0] = stack[0];	/* x0 (argc) */

}

#ifdef CONFIG_COMPAT

static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc,

				       unsigned long sp)

{

	unsigned int *stack = (unsigned int *)sp;

	start_thread_common(regs, pc);

	regs->pstate = COMPAT_PSR_MODE_USR;

	if (pc & 1)

		regs->pstate |= COMPAT_PSR_T_BIT;

	regs->compat_sp = sp;

	regs->regs[2] = stack[2];	/* x2 (envp) */

	regs->regs[1] = stack[1];	/* x1 (argv) */

	regs->regs[0] = stack[0];	/* x0 (argc) */

}

#endif

/* Forward declaration, a strange C thing */

struct task_struct;

/* Free all resources held by a thread. */

extern void release_thread(struct task_struct *);

/* Prepare to copy thread state - unlazy all lazy status */

#define prepare_to_copy(tsk)	do { } while (0)

unsigned long get_wchan(struct task_struct *p);

#define cpu_relax()			barrier()

/* Thread switching */

extern struct task_struct *cpu_switch_to(struct task_struct *prev,

					 struct task_struct *next);

/*

 * Create a new kernel thread

 */

extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);

#define task_pt_regs(p) \

	((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)

#define KSTK_EIP(tsk)	task_pt_regs(tsk)->pc

#define KSTK_ESP(tsk)	task_pt_regs(tsk)->sp

/*

 * Prefetching support

 */

#define ARCH_HAS_PREFETCH

static inline void prefetch(const void *ptr)

{

	asm volatile("prfm pldl1keep, %a0\n" : : "p" (ptr));

}

#define ARCH_HAS_PREFETCHW

static inline void prefetchw(const void *ptr)

{

	asm volatile("prfm pstl1keep, %a0\n" : : "p" (ptr));

}

#define ARCH_HAS_SPINLOCK_PREFETCH

static inline void spin_lock_prefetch(const void *x)

{

	prefetchw(x);

}

#define HAVE_ARCH_PICK_MMAP_LAYOUT

#endif

#endif /* __ASM_PROCESSOR_H */

/*

 * arch/arm64/kernel/cputable.c

 *

 * Copyright (C) 2012 ARM Ltd.

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

#include <linux/init.h>

#include <asm/cputable.h>

extern unsigned long __cpu_setup(void);

struct cpu_info __initdata cpu_table[] = {

	{

		.cpu_id_val	= 0x000f0000,

		.cpu_id_mask	= 0x000f0000,

		.cpu_name	= "AArch64 Processor",

		.cpu_setup	= __cpu_setup,

	},

	{ /* Empty */ },

};