/* SPDX-License-Identifier: GPL-2.0 */
/*
 * include/asm-parisc/processor.h
 *
 * Copyright (C) 1994 Linus Torvalds
 * Copyright (C) 2001 Grant Grundler
 */

#ifndef __ASM_PARISC_PROCESSOR_H
#define __ASM_PARISC_PROCESSOR_H

#ifndef __ASSEMBLER__
#include <linux/threads.h>
#include <linux/irqreturn.h>

#include <asm/assembly.h>
#include <asm/prefetch.h>
#include <asm/hardware.h>
#include <asm/pdc.h>
#include <asm/ptrace.h>
#include <asm/types.h>
#include <asm/percpu.h>
#endif /* __ASSEMBLER__ */

#define HAVE_ARCH_PICK_MMAP_LAYOUT

#define TASK_SIZE_OF(tsk)       ((tsk)->thread.task_size)
#define TASK_SIZE               TASK_SIZE_OF(current)
#define TASK_UNMAPPED_BASE      (current->thread.map_base)

#define DEFAULT_TASK_SIZE32     (0xFFF00000UL)
#define DEFAULT_MAP_BASE32      (0x40000000UL)

#ifdef CONFIG_64BIT
#define DEFAULT_TASK_SIZE       (MAX_ADDRESS-0xf000000)
#define DEFAULT_MAP_BASE        (0x200000000UL)
#else
#define DEFAULT_TASK_SIZE       DEFAULT_TASK_SIZE32
#define DEFAULT_MAP_BASE        DEFAULT_MAP_BASE32
#endif

/* XXX: STACK_TOP actually should be STACK_BOTTOM for parisc.
 * prumpf */

#define STACK_TOP       TASK_SIZE
#define STACK_TOP_MAX   DEFAULT_TASK_SIZE

#ifndef __ASSEMBLER__

struct rlimit;
unsigned long mmap_upper_limit(const struct rlimit *rlim_stack);
unsigned long calc_max_stack_size(unsigned long stack_max);

/*
 * Data detected about CPUs at boot time which is the same for all CPU's.
 * HP boxes are SMP - ie identical processors.
 *
 * FIXME: some CPU rev info may be processor specific...
 */
struct system_cpuinfo_parisc {
        unsigned int    cpu_count;
        unsigned int    cpu_hz;
        unsigned int    hversion;
        unsigned int    sversion;
        enum cpu_type   cpu_type;

        struct {
                struct pdc_model model;
                unsigned long versions;
                unsigned long cpuid;
                unsigned long capabilities;
                char   sys_model_name[81]; /* PDC-ROM returnes this model name */
        } pdc;

        const char      *cpu_name;      /* e.g. "PA7300LC (PCX-L2)" */
        const char      *family_name;   /* e.g. "1.1e" */
};


/* Per CPU data structure - ie varies per CPU.  */
struct cpuinfo_parisc {
        unsigned long it_value;     /* Interval Timer at last timer Intr */
        unsigned long irq_count;    /* number of IRQ's since boot */
        unsigned long cpuid;        /* aka slot_number or set to NO_PROC_ID */
        unsigned long hpa;          /* Host Physical address */
        unsigned long txn_addr;     /* MMIO addr of EIR or id_eid */
#ifdef CONFIG_SMP
        unsigned long pending_ipi;  /* bitmap of type ipi_message_type */
#endif
        unsigned long bh_count;     /* number of times bh was invoked */
        unsigned long fp_rev;
        unsigned long fp_model;
        unsigned long cpu_num;      /* CPU number from PAT firmware */
        unsigned long cpu_loc;      /* CPU location from PAT firmware */
        unsigned int state;
        struct parisc_device *dev;
};

extern struct system_cpuinfo_parisc boot_cpu_data;
DECLARE_PER_CPU(struct cpuinfo_parisc, cpu_data);
extern int time_keeper_id;              /* CPU used for timekeeping */

#define CPU_HVERSION ((boot_cpu_data.hversion >> 4) & 0x0FFF)

struct thread_struct {
        struct pt_regs regs;
        unsigned long  task_size;
        unsigned long  map_base;
        unsigned long  flags;
}; 

#define task_pt_regs(tsk) ((struct pt_regs *)&((tsk)->thread.regs))

/* Thread struct flags. */
#define PARISC_UAC_NOPRINT      (1UL << 0)      /* see prctl and unaligned.c */
#define PARISC_UAC_SIGBUS       (1UL << 1)
#define PARISC_KERNEL_DEATH     (1UL << 31)     /* see die_if_kernel()... */

#define PARISC_UAC_SHIFT        0
#define PARISC_UAC_MASK         (PARISC_UAC_NOPRINT|PARISC_UAC_SIGBUS)

#define SET_UNALIGN_CTL(task,value)                                       \
        ({                                                                \
        (task)->thread.flags = (((task)->thread.flags & ~PARISC_UAC_MASK) \
                                | (((value) << PARISC_UAC_SHIFT) &        \
                                   PARISC_UAC_MASK));                     \
        0;                                                                \
        })

#define GET_UNALIGN_CTL(task,addr)                                        \
        ({                                                                \
        put_user(((task)->thread.flags & PARISC_UAC_MASK)                 \
                 >> PARISC_UAC_SHIFT, (int __user *) (addr));             \
        })

#define INIT_THREAD { \
        .regs = {       .gr     = { 0, }, \
                        .fr     = { 0, }, \
                        .sr     = { 0, }, \
                        .iasq   = { 0, }, \
                        .iaoq   = { 0, }, \
                        .cr27   = 0, \
                }, \
        .task_size      = DEFAULT_TASK_SIZE, \
        .map_base       = DEFAULT_MAP_BASE, \
        .flags          = 0 \
        }

struct task_struct;
void show_trace(struct task_struct *task, unsigned long *stack);

/*
 * Start user thread in another space.
 *
 * Note that we set both the iaoq and r31 to the new pc. When
 * the kernel initially calls execve it will return through an
 * rfi path that will use the values in the iaoq. The execve
 * syscall path will return through the gateway page, and
 * that uses r31 to branch to.
 *
 * For ELF we clear r23, because the dynamic linker uses it to pass
 * the address of the finalizer function.
 *
 * We also initialize sr3 to an illegal value (illegal for our
 * implementation, not for the architecture).
 */
typedef unsigned int elf_caddr_t;

/* The ELF abi wants things done a "wee bit" differently than
 * som does.  Supporting this behavior here avoids
 * having our own version of create_elf_tables.
 *
 * Oh, and yes, that is not a typo, we are really passing argc in r25
 * and argv in r24 (rather than r26 and r25).  This is because that's
 * where __libc_start_main wants them.
 *
 * Duplicated from dl-machine.h for the benefit of readers:
 *
 *  Our initial stack layout is rather different from everyone else's
 *  due to the unique PA-RISC ABI.  As far as I know it looks like
 *  this:

   -----------------------------------  (user startup code creates this frame)
   |         32 bytes of magic       |
   |---------------------------------|
   | 32 bytes argument/sp save area  |
   |---------------------------------| (bprm->p)
   |        ELF auxiliary info       |
   |         (up to 28 words)        |
   |---------------------------------|
   |               NULL              |
   |---------------------------------|
   |       Environment pointers      |
   |---------------------------------|
   |               NULL              |
   |---------------------------------|
   |        Argument pointers        |
   |---------------------------------| <- argv
   |          argc (1 word)          |
   |---------------------------------| <- bprm->exec (HACK!)
   |         N bytes of slack        |
   |---------------------------------|
   |    filename passed to execve    |
   |---------------------------------| (mm->env_end)
   |           env strings           |
   |---------------------------------| (mm->env_start, mm->arg_end)
   |           arg strings           |
   |---------------------------------|
   | additional faked arg strings if |
   | we're invoked via binfmt_script |
   |---------------------------------| (mm->arg_start)
   stack base is at TASK_SIZE - rlim_max.

on downward growing arches, it looks like this:
   stack base at TASK_SIZE
   | filename passed to execve
   | env strings
   | arg strings
   | faked arg strings
   | slack
   | ELF
   | envps
   | argvs
   | argc

 *  The pleasant part of this is that if we need to skip arguments we
 *  can just decrement argc and move argv, because the stack pointer
 *  is utterly unrelated to the location of the environment and
 *  argument vectors.
 *
 * Note that the S/390 people took the easy way out and hacked their
 * GCC to make the stack grow downwards.
 *
 * Final Note: For entry from syscall, the W (wide) bit of the PSW
 * is stuffed into the lowest bit of the user sp (%r30), so we fill
 * it in here from the current->personality
 */

#define USER_WIDE_MODE  (!is_32bit_task())

#define start_thread(regs, new_pc, new_sp) do {         \
        elf_addr_t *sp = (elf_addr_t *)new_sp;          \
        __u32 spaceid = (__u32)current->mm->context.space_id;   \
        elf_addr_t pc = (elf_addr_t)new_pc | 3;         \
        elf_caddr_t *argv = (elf_caddr_t *)bprm->exec + 1;      \
                                                        \
        regs->iasq[0] = spaceid;                        \
        regs->iasq[1] = spaceid;                        \
        regs->iaoq[0] = pc;                             \
        regs->iaoq[1] = pc + 4;                         \
        regs->sr[2] = LINUX_GATEWAY_SPACE;              \
        regs->sr[3] = 0xffff;                           \
        regs->sr[4] = spaceid;                          \
        regs->sr[5] = spaceid;                          \
        regs->sr[6] = spaceid;                          \
        regs->sr[7] = spaceid;                          \
        regs->gr[ 0] = USER_PSW | (USER_WIDE_MODE ? PSW_W : 0); \
        regs->fr[ 0] = 0LL;                             \
        regs->fr[ 1] = 0LL;                             \
        regs->fr[ 2] = 0LL;                             \
        regs->fr[ 3] = 0LL;                             \
        regs->gr[30] = (((unsigned long)sp + 63) &~ 63) | (USER_WIDE_MODE ? 1 : 0); \
        regs->gr[31] = pc;                              \
                                                        \
        get_user(regs->gr[25], (argv - 1));             \
        regs->gr[24] = (long) argv;                     \
        regs->gr[23] = 0;                               \
} while(0)

struct mm_struct;

extern unsigned long __get_wchan(struct task_struct *p);

#define KSTK_EIP(tsk)   ((tsk)->thread.regs.iaoq[0])
#define KSTK_ESP(tsk)   ((tsk)->thread.regs.gr[30])

#define cpu_relax()     barrier()

/*
 * parisc_requires_coherency() is used to identify the combined VIPT/PIPT
 * cached CPUs which require a guarantee of coherency (no inequivalent aliases
 * with different data, whether clean or not) to operate
 */
#ifdef CONFIG_PA8X00
extern int _parisc_requires_coherency;
#define parisc_requires_coherency()     _parisc_requires_coherency
#else
#define parisc_requires_coherency()     (0)
#endif

extern int running_on_qemu;
extern int parisc_narrow_firmware;

extern void __noreturn toc_intr(struct pt_regs *regs);
extern void toc_handler(void);
extern unsigned int toc_handler_size;
extern unsigned int toc_handler_csum;
extern void do_cpu_irq_mask(struct pt_regs *);
extern irqreturn_t timer_interrupt(int, void *);
extern irqreturn_t ipi_interrupt(int, void *);
extern void parisc_clockevent_init(void);
extern void handle_interruption(int, struct pt_regs *);

/* called from assembly code: */
extern void start_parisc(void);
extern void smp_callin(unsigned long);
extern void sys_rt_sigreturn(struct pt_regs *, int);
extern void do_notify_resume(struct pt_regs *, long);
extern long do_syscall_trace_enter(struct pt_regs *);
extern void do_syscall_trace_exit(struct pt_regs *);

/* CPU startup and info */
struct seq_file;
extern void early_trap_init(void);
extern void collect_boot_cpu_data(void);
extern void btlb_init_per_cpu(void);
extern int show_cpuinfo (struct seq_file *m, void *v);

/* driver code in driver/parisc */
extern void processor_init(void);
struct parisc_device;
struct resource;
extern void sba_distributed_lmmio(struct parisc_device *, struct resource *);
extern void sba_directed_lmmio(struct parisc_device *, struct resource *);
extern void lba_set_iregs(struct parisc_device *lba, u32 ibase, u32 imask);
extern void ccio_cujo20_fixup(struct parisc_device *dev, u32 iovp);

#endif /* __ASSEMBLER__ */

#endif /* __ASM_PARISC_PROCESSOR_H */