[SPARC64]: Add infrastructure for dynamic TSB sizing.
This also cleans up tsb_context_switch(). The assembler
routine is now __tsb_context_switch() and the former is
an inline function that picks out the bits from the mm_struct
and passes it into the assembler code as arguments.
setup_tsb_parms() computes the locked TLB entry to map the
TSB. Later when we support using the physical address quad
load instructions of Cheetah+ and later, we'll simply use
the physical address for the TSB register value and set
the map virtual and PTE both to zero.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc64/kernel/binfmt_aout32.c b/arch/sparc64/kernel/binfmt_aout32.c
index a57d7f2..181c8cd 100644
--- a/arch/sparc64/kernel/binfmt_aout32.c
+++ b/arch/sparc64/kernel/binfmt_aout32.c
@@ -330,8 +330,7 @@
current->mm->start_stack =
(unsigned long) create_aout32_tables((char __user *)bprm->p, bprm);
- tsb_context_switch(__pa(current->mm->pgd),
- current->mm->context.sparc64_tsb);
+ tsb_context_switch(mm);
start_thread32(regs, ex.a_entry, current->mm->start_stack);
if (current->ptrace & PT_PTRACED)
diff --git a/arch/sparc64/kernel/process.c b/arch/sparc64/kernel/process.c
index 2784aab..26548fc 100644
--- a/arch/sparc64/kernel/process.c
+++ b/arch/sparc64/kernel/process.c
@@ -441,8 +441,7 @@
mm = t->task->mm;
if (mm)
- tsb_context_switch(__pa(mm->pgd),
- mm->context.sparc64_tsb);
+ tsb_context_switch(mm);
set_thread_wsaved(0);
diff --git a/arch/sparc64/kernel/tsb.S b/arch/sparc64/kernel/tsb.S
index 76f2c0b..fe266ba 100644
--- a/arch/sparc64/kernel/tsb.S
+++ b/arch/sparc64/kernel/tsb.S
@@ -130,48 +130,36 @@
* schedule() time.
*
* %o0: page table physical address
- * %o1: TSB address
+ * %o1: TSB register value
+ * %o2: TSB virtual address
+ * %o3: TSB mapping locked PTE
+ *
+ * We have to run this whole thing with interrupts
+ * disabled so that the current cpu doesn't change
+ * due to preemption.
*/
.align 32
- .globl tsb_context_switch
-tsb_context_switch:
+ .globl __tsb_context_switch
+__tsb_context_switch:
rdpr %pstate, %o5
wrpr %o5, PSTATE_IE, %pstate
- ldub [%g6 + TI_CPU], %o3
- sethi %hi(trap_block), %o4
- sllx %o3, TRAP_BLOCK_SZ_SHIFT, %o3
- or %o4, %lo(trap_block), %o4
- add %o4, %o3, %o4
- stx %o0, [%o4 + TRAP_PER_CPU_PGD_PADDR]
+ ldub [%g6 + TI_CPU], %g1
+ sethi %hi(trap_block), %g2
+ sllx %g1, TRAP_BLOCK_SZ_SHIFT, %g1
+ or %g2, %lo(trap_block), %g2
+ add %g2, %g1, %g2
+ stx %o0, [%g2 + TRAP_PER_CPU_PGD_PADDR]
- brgez %o1, 9f
- nop
-
- /* Lock TSB into D-TLB. */
- sethi %hi(PAGE_SIZE), %o3
- and %o3, %o1, %o3
- sethi %hi(TSBMAP_BASE), %o2
- add %o2, %o3, %o2
-
- /* XXX handle PAGE_SIZE != 8K correctly... */
mov TSB_REG, %g1
- stxa %o2, [%g1] ASI_DMMU
+ stxa %o1, [%g1] ASI_DMMU
membar #Sync
- stxa %o2, [%g1] ASI_IMMU
+ stxa %o1, [%g1] ASI_IMMU
membar #Sync
-#define KERN_HIGHBITS ((_PAGE_VALID|_PAGE_SZBITS)^0xfffff80000000000)
-#define KERN_LOWBITS (_PAGE_CP | _PAGE_CV | _PAGE_P | _PAGE_W | _PAGE_L)
- sethi %uhi(KERN_HIGHBITS), %g2
- or %g2, %ulo(KERN_HIGHBITS), %g2
- sllx %g2, 32, %g2
- or %g2, KERN_LOWBITS, %g2
-#undef KERN_HIGHBITS
-#undef KERN_LOWBITS
-
- xor %o1, %g2, %o1
+ brz %o2, 9f
+ nop
/* We use entry 61 for this locked entry. This is the spitfire
* TLB entry number, and luckily cheetah masks the value with
@@ -184,11 +172,10 @@
stxa %o2, [%g1] ASI_DMMU
membar #Sync
mov (61 << 3), %g1
- stxa %o1, [%g1] ASI_DTLB_DATA_ACCESS
+ stxa %o3, [%g1] ASI_DTLB_DATA_ACCESS
membar #Sync
-
9:
wrpr %o5, %pstate
retl
- mov %o2, %o0
+ nop
diff --git a/arch/sparc64/mm/tsb.c b/arch/sparc64/mm/tsb.c
index 2f84cef..dfe7144 100644
--- a/arch/sparc64/mm/tsb.c
+++ b/arch/sparc64/mm/tsb.c
@@ -9,13 +9,7 @@
#include <asm/tlbflush.h>
#include <asm/tlb.h>
#include <asm/mmu_context.h>
-
-#define TSB_ENTRY_ALIGNMENT 16
-
-struct tsb {
- unsigned long tag;
- unsigned long pte;
-} __attribute__((aligned(TSB_ENTRY_ALIGNMENT)));
+#include <asm/pgtable.h>
/* We use an 8K TSB for the whole kernel, this allows to
* handle about 4MB of modules and vmalloc mappings without
@@ -27,10 +21,10 @@
extern struct tsb swapper_tsb[KERNEL_TSB_NENTRIES];
-static inline unsigned long tsb_hash(unsigned long vaddr)
+static inline unsigned long tsb_hash(unsigned long vaddr, unsigned long nentries)
{
vaddr >>= PAGE_SHIFT;
- return vaddr & (KERNEL_TSB_NENTRIES - 1);
+ return vaddr & (nentries - 1);
}
static inline int tag_compare(struct tsb *entry, unsigned long vaddr, unsigned long context)
@@ -51,7 +45,8 @@
unsigned long v;
for (v = start; v < end; v += PAGE_SIZE) {
- struct tsb *ent = &swapper_tsb[tsb_hash(v)];
+ unsigned long hash = tsb_hash(v, KERNEL_TSB_NENTRIES);
+ struct tsb *ent = &swapper_tsb[hash];
if (tag_compare(ent, v, 0)) {
ent->tag = 0UL;
@@ -63,8 +58,9 @@
void flush_tsb_user(struct mmu_gather *mp)
{
struct mm_struct *mm = mp->mm;
- struct tsb *tsb = (struct tsb *) mm->context.sparc64_tsb;
+ struct tsb *tsb = mm->context.tsb;
unsigned long ctx = ~0UL;
+ unsigned long nentries = mm->context.tsb_nentries;
int i;
if (CTX_VALID(mm->context))
@@ -76,7 +72,7 @@
v &= ~0x1UL;
- ent = &tsb[tsb_hash(v)];
+ ent = &tsb[tsb_hash(v, nentries)];
if (tag_compare(ent, v, ctx)) {
ent->tag = 0UL;
membar_storeload_storestore();
@@ -84,6 +80,83 @@
}
}
+static void setup_tsb_params(struct mm_struct *mm, unsigned long tsb_bytes)
+{
+ unsigned long tsb_reg, base, tsb_paddr;
+ unsigned long page_sz, tte;
+
+ mm->context.tsb_nentries = tsb_bytes / sizeof(struct tsb);
+
+ base = TSBMAP_BASE;
+ tte = (_PAGE_VALID | _PAGE_L | _PAGE_CP |
+ _PAGE_CV | _PAGE_P | _PAGE_W);
+ tsb_paddr = __pa(mm->context.tsb);
+
+ /* Use the smallest page size that can map the whole TSB
+ * in one TLB entry.
+ */
+ switch (tsb_bytes) {
+ case 8192 << 0:
+ tsb_reg = 0x0UL;
+#ifdef DCACHE_ALIASING_POSSIBLE
+ base += (tsb_paddr & 8192);
+#endif
+ tte |= _PAGE_SZ8K;
+ page_sz = 8192;
+ break;
+
+ case 8192 << 1:
+ tsb_reg = 0x1UL;
+ tte |= _PAGE_SZ64K;
+ page_sz = 64 * 1024;
+ break;
+
+ case 8192 << 2:
+ tsb_reg = 0x2UL;
+ tte |= _PAGE_SZ64K;
+ page_sz = 64 * 1024;
+ break;
+
+ case 8192 << 3:
+ tsb_reg = 0x3UL;
+ tte |= _PAGE_SZ64K;
+ page_sz = 64 * 1024;
+ break;
+
+ case 8192 << 4:
+ tsb_reg = 0x4UL;
+ tte |= _PAGE_SZ512K;
+ page_sz = 512 * 1024;
+ break;
+
+ case 8192 << 5:
+ tsb_reg = 0x5UL;
+ tte |= _PAGE_SZ512K;
+ page_sz = 512 * 1024;
+ break;
+
+ case 8192 << 6:
+ tsb_reg = 0x6UL;
+ tte |= _PAGE_SZ512K;
+ page_sz = 512 * 1024;
+ break;
+
+ case 8192 << 7:
+ tsb_reg = 0x7UL;
+ tte |= _PAGE_SZ4MB;
+ page_sz = 4 * 1024 * 1024;
+ break;
+ };
+
+ tsb_reg |= base;
+ tsb_reg |= (tsb_paddr & (page_sz - 1UL));
+ tte |= (tsb_paddr & ~(page_sz - 1UL));
+
+ mm->context.tsb_reg_val = tsb_reg;
+ mm->context.tsb_map_vaddr = base;
+ mm->context.tsb_map_pte = tte;
+}
+
int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
{
unsigned long page = get_zeroed_page(GFP_KERNEL);
@@ -92,14 +165,22 @@
if (unlikely(!page))
return -ENOMEM;
- mm->context.sparc64_tsb = (unsigned long *) page;
+ mm->context.tsb = (struct tsb *) page;
+ setup_tsb_params(mm, PAGE_SIZE);
return 0;
}
void destroy_context(struct mm_struct *mm)
{
- free_page((unsigned long) mm->context.sparc64_tsb);
+ free_page((unsigned long) mm->context.tsb);
+
+ /* We can remove these later, but for now it's useful
+ * to catch any bogus post-destroy_context() references
+ * to the TSB.
+ */
+ mm->context.tsb = NULL;
+ mm->context.tsb_reg_val = 0UL;
spin_lock(&ctx_alloc_lock);
diff --git a/include/asm-sparc64/mmu.h b/include/asm-sparc64/mmu.h
index 36384cf..2effeba 100644
--- a/include/asm-sparc64/mmu.h
+++ b/include/asm-sparc64/mmu.h
@@ -90,9 +90,20 @@
#ifndef __ASSEMBLY__
+#define TSB_ENTRY_ALIGNMENT 16
+
+struct tsb {
+ unsigned long tag;
+ unsigned long pte;
+} __attribute__((aligned(TSB_ENTRY_ALIGNMENT)));
+
typedef struct {
unsigned long sparc64_ctx_val;
- unsigned long *sparc64_tsb;
+ struct tsb *tsb;
+ unsigned long tsb_nentries;
+ unsigned long tsb_reg_val;
+ unsigned long tsb_map_vaddr;
+ unsigned long tsb_map_pte;
} mm_context_t;
#endif /* !__ASSEMBLY__ */
diff --git a/include/asm-sparc64/mmu_context.h b/include/asm-sparc64/mmu_context.h
index 0dffb4c..0a950f1 100644
--- a/include/asm-sparc64/mmu_context.h
+++ b/include/asm-sparc64/mmu_context.h
@@ -22,7 +22,15 @@
extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
extern void destroy_context(struct mm_struct *mm);
-extern unsigned long tsb_context_switch(unsigned long pgd_pa, unsigned long *tsb);
+extern void __tsb_context_switch(unsigned long pgd_pa, unsigned long tsb_reg,
+ unsigned long tsb_vaddr, unsigned long tsb_pte);
+
+static inline void tsb_context_switch(struct mm_struct *mm)
+{
+ __tsb_context_switch(__pa(mm->pgd), mm->context.tsb_reg_val,
+ mm->context.tsb_map_vaddr,
+ mm->context.tsb_map_pte);
+}
/* Set MMU context in the actual hardware. */
#define load_secondary_context(__mm) \
@@ -52,8 +60,7 @@
if (!ctx_valid || (old_mm != mm)) {
load_secondary_context(mm);
- tsb_context_switch(__pa(mm->pgd),
- mm->context.sparc64_tsb);
+ tsb_context_switch(mm);
}
/* Even if (mm == old_mm) we _must_ check
@@ -91,7 +98,7 @@
load_secondary_context(mm);
__flush_tlb_mm(CTX_HWBITS(mm->context), SECONDARY_CONTEXT);
- tsb_context_switch(__pa(mm->pgd), mm->context.sparc64_tsb);
+ tsb_context_switch(mm);
}
#endif /* !(__ASSEMBLY__) */
diff --git a/include/asm-sparc64/tsb.h b/include/asm-sparc64/tsb.h
index 03d272e..1f93b7d 100644
--- a/include/asm-sparc64/tsb.h
+++ b/include/asm-sparc64/tsb.h
@@ -19,7 +19,7 @@
* stxa %g5, [%g0] ASI_{D,I}TLB_DATA_IN
* retry
*
-
+ *
* Each 16-byte slot of the TSB is the 8-byte tag and then the 8-byte
* PTE. The TAG is of the same layout as the TLB TAG TARGET mmu
* register which is: