/* Called in schedule() just before actually doing the switch_to. */
void
switch_mm(struct mm_struct *prev, struct mm_struct *next,
struct task_struct *tsk)
{
if (prev != next) {
int cpu = smp_processor_id();
/* Make sure there is a MMU context. */
spin_lock(&mmu_context_lock);
get_mmu_context(next);
cpu_set(cpu, next->cpu_vm_mask);
spin_unlock(&mmu_context_lock);
/*
* Remember the pgd for the fault handlers. Keep a seperate
* copy of it because current and active_mm might be invalid
* at points where * there's still a need to derefer the pgd.
*/
per_cpu(current_pgd, cpu) = next->pgd;
/* Switch context in the MMU. */
if (tsk && task_thread_info(tsk)) {
SPEC_REG_WR(SPEC_REG_PID, next->context.page_id |
task_thread_info(tsk)->tls);
} else {
SPEC_REG_WR(SPEC_REG_PID, next->context.page_id);
}
}
}
static long get_debugreg(long pid, unsigned int regno)
{
register int old_srs;
register long data;
if (pid != bp_owner) {
return 0;
}
/* Remember old SRS. */
SPEC_REG_RD(SPEC_REG_SRS, old_srs);
/* Switch to BP bank. */
SUPP_BANK_SEL(BANK_BP);
switch (regno - PT_BP) {
case 0:
SUPP_REG_RD(0, data); break;
case 1:
case 2:
/* error return value? */
data = 0;
break;
case 3:
SUPP_REG_RD(3, data); break;
case 4:
SUPP_REG_RD(4, data); break;
case 5:
SUPP_REG_RD(5, data); break;
case 6:
SUPP_REG_RD(6, data); break;
case 7:
SUPP_REG_RD(7, data); break;
case 8:
SUPP_REG_RD(8, data); break;
case 9:
SUPP_REG_RD(9, data); break;
case 10:
SUPP_REG_RD(10, data); break;
case 11:
SUPP_REG_RD(11, data); break;
case 12:
SUPP_REG_RD(12, data); break;
case 13:
SUPP_REG_RD(13, data); break;
case 14:
SUPP_REG_RD(14, data); break;
default:
/* error return value? */
data = 0;
}
/* Restore SRS. */
SPEC_REG_WR(SPEC_REG_SRS, old_srs);
/* Just for show. */
NOP();
NOP();
NOP();
return data;
}
/*
* The kernel is already mapped with linear mapping at kseg_c so there's no
* need to map it with a page table. However, head.S also temporarily mapped it
* at kseg_4 thus the ksegs are set up again. Also clear the TLB and do various
* other paging stuff.
*/
void __init
cris_mmu_init(void)
{
unsigned long mmu_config;
unsigned long mmu_kbase_hi;
unsigned long mmu_kbase_lo;
unsigned short mmu_page_id;
/*
* Make sure the current pgd table points to something sane, even if it
* is most probably not used until the next switch_mm.
*/
per_cpu(current_pgd, smp_processor_id()) = init_mm.pgd;
#ifdef CONFIG_SMP
{
pgd_t **pgd;
pgd = (pgd_t**)&per_cpu(current_pgd, smp_processor_id());
SUPP_BANK_SEL(1);
SUPP_REG_WR(RW_MM_TLB_PGD, pgd);
SUPP_BANK_SEL(2);
SUPP_REG_WR(RW_MM_TLB_PGD, pgd);
}
#endif
/* Initialise the TLB. Function found in tlb.c. */
tlb_init();
/* Enable exceptions and initialize the kernel segments. */
mmu_config = ( REG_STATE(mmu, rw_mm_cfg, we, on) |
REG_STATE(mmu, rw_mm_cfg, acc, on) |
REG_STATE(mmu, rw_mm_cfg, ex, on) |
REG_STATE(mmu, rw_mm_cfg, inv, on) |
REG_STATE(mmu, rw_mm_cfg, seg_f, linear) |
REG_STATE(mmu, rw_mm_cfg, seg_e, linear) |
REG_STATE(mmu, rw_mm_cfg, seg_d, page) |
REG_STATE(mmu, rw_mm_cfg, seg_c, linear) |
REG_STATE(mmu, rw_mm_cfg, seg_b, linear) |
#ifndef CONFIG_ETRAX_VCS_SIM
REG_STATE(mmu, rw_mm_cfg, seg_a, page) |
#else
REG_STATE(mmu, rw_mm_cfg, seg_a, linear) |
#endif
REG_STATE(mmu, rw_mm_cfg, seg_9, page) |
REG_STATE(mmu, rw_mm_cfg, seg_8, page) |
REG_STATE(mmu, rw_mm_cfg, seg_7, page) |
REG_STATE(mmu, rw_mm_cfg, seg_6, page) |
REG_STATE(mmu, rw_mm_cfg, seg_5, page) |
REG_STATE(mmu, rw_mm_cfg, seg_4, page) |
REG_STATE(mmu, rw_mm_cfg, seg_3, page) |
REG_STATE(mmu, rw_mm_cfg, seg_2, page) |
REG_STATE(mmu, rw_mm_cfg, seg_1, page) |
REG_STATE(mmu, rw_mm_cfg, seg_0, page));
mmu_kbase_hi = ( REG_FIELD(mmu, rw_mm_kbase_hi, base_f, 0x0) |
REG_FIELD(mmu, rw_mm_kbase_hi, base_e, 0x8) |
REG_FIELD(mmu, rw_mm_kbase_hi, base_d, 0x0) |
REG_FIELD(mmu, rw_mm_kbase_hi, base_c, 0x4) |
REG_FIELD(mmu, rw_mm_kbase_hi, base_b, 0xb) |
#ifndef CONFIG_ETRAX_VCS_SIM
REG_FIELD(mmu, rw_mm_kbase_hi, base_a, 0x0) |
#else
REG_FIELD(mmu, rw_mm_kbase_hi, base_a, 0xa) |
#endif
REG_FIELD(mmu, rw_mm_kbase_hi, base_9, 0x0) |
REG_FIELD(mmu, rw_mm_kbase_hi, base_8, 0x0));
mmu_kbase_lo = ( REG_FIELD(mmu, rw_mm_kbase_lo, base_7, 0x0) |
REG_FIELD(mmu, rw_mm_kbase_lo, base_6, 0x0) |
REG_FIELD(mmu, rw_mm_kbase_lo, base_5, 0x0) |
REG_FIELD(mmu, rw_mm_kbase_lo, base_4, 0x0) |
REG_FIELD(mmu, rw_mm_kbase_lo, base_3, 0x0) |
REG_FIELD(mmu, rw_mm_kbase_lo, base_2, 0x0) |
REG_FIELD(mmu, rw_mm_kbase_lo, base_1, 0x0) |
REG_FIELD(mmu, rw_mm_kbase_lo, base_0, 0x0));
mmu_page_id = REG_FIELD(mmu, rw_mm_tlb_hi, pid, 0);
/* Update the instruction MMU. */
SUPP_BANK_SEL(BANK_IM);
SUPP_REG_WR(RW_MM_CFG, mmu_config);
SUPP_REG_WR(RW_MM_KBASE_HI, mmu_kbase_hi);
SUPP_REG_WR(RW_MM_KBASE_LO, mmu_kbase_lo);
SUPP_REG_WR(RW_MM_TLB_HI, mmu_page_id);
/* Update the data MMU. */
SUPP_BANK_SEL(BANK_DM);
SUPP_REG_WR(RW_MM_CFG, mmu_config);
SUPP_REG_WR(RW_MM_KBASE_HI, mmu_kbase_hi);
SUPP_REG_WR(RW_MM_KBASE_LO, mmu_kbase_lo);
SUPP_REG_WR(RW_MM_TLB_HI, mmu_page_id);
SPEC_REG_WR(SPEC_REG_PID, 0);
/*
* The MMU has been enabled ever since head.S but just to make it
* totally obvious enable it here as well.
*/
SUPP_BANK_SEL(BANK_GC);
SUPP_REG_WR(RW_GC_CFG, 0xf); /* IMMU, DMMU, ICache, DCache on */
}
static int put_debugreg(long pid, unsigned int regno, long data)
{
int ret = 0;
register int old_srs;
#ifdef CONFIG_ETRAX_KGDB
/* Ignore write, but pretend it was ok if value is 0
(we don't want POKEUSR/SETREGS failing unnessecarily). */
return (data == 0) ? ret : -1;
#endif
/* Simple owner management. */
if (!bp_owner)
bp_owner = pid;
else if (bp_owner != pid) {
/* Ignore write, but pretend it was ok if value is 0
(we don't want POKEUSR/SETREGS failing unnessecarily). */
return (data == 0) ? ret : -1;
}
/* Remember old SRS. */
SPEC_REG_RD(SPEC_REG_SRS, old_srs);
/* Switch to BP bank. */
SUPP_BANK_SEL(BANK_BP);
switch (regno - PT_BP) {
case 0:
SUPP_REG_WR(0, data); break;
case 1:
case 2:
if (data)
ret = -1;
break;
case 3:
SUPP_REG_WR(3, data); break;
case 4:
SUPP_REG_WR(4, data); break;
case 5:
SUPP_REG_WR(5, data); break;
case 6:
SUPP_REG_WR(6, data); break;
case 7:
SUPP_REG_WR(7, data); break;
case 8:
SUPP_REG_WR(8, data); break;
case 9:
SUPP_REG_WR(9, data); break;
case 10:
SUPP_REG_WR(10, data); break;
case 11:
SUPP_REG_WR(11, data); break;
case 12:
SUPP_REG_WR(12, data); break;
case 13:
SUPP_REG_WR(13, data); break;
case 14:
SUPP_REG_WR(14, data); break;
default:
ret = -1;
break;
}
/* Restore SRS. */
SPEC_REG_WR(SPEC_REG_SRS, old_srs);
/* Just for show. */
NOP();
NOP();
NOP();
return ret;
}
