summaryrefslogtreecommitdiff
path: root/target-cris/mmu.c
diff options
context:
space:
mode:
authoredgar_igl <edgar_igl@c046a42c-6fe2-441c-8c8c-71466251a162>2008-05-11 14:28:14 +0000
committeredgar_igl <edgar_igl@c046a42c-6fe2-441c-8c8c-71466251a162>2008-05-11 14:28:14 +0000
commit44cd42ee4082813cc4b45117bbb6156920957e47 (patch)
tree631debf76b3fa1205ad50ef1e4ae268ce236de84 /target-cris/mmu.c
parent868314358ea3f3009fb72d2867dc73af54338ae7 (diff)
downloadqemu-44cd42ee4082813cc4b45117bbb6156920957e47.tar.gz
CRIS: Add support for the pseudo randomized set that the mmu provides with TLB refill faults. This makes linux guests use the four way TLB set associativty.
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4425 c046a42c-6fe2-441c-8c8c-71466251a162
Diffstat (limited to 'target-cris/mmu.c')
-rw-r--r--target-cris/mmu.c49
1 files changed, 36 insertions, 13 deletions
diff --git a/target-cris/mmu.c b/target-cris/mmu.c
index 5ec9b37757..bec89e685b 100644
--- a/target-cris/mmu.c
+++ b/target-cris/mmu.c
@@ -32,6 +32,24 @@
#define D(x)
+void cris_mmu_init(CPUState *env)
+{
+ env->mmu_rand_lfsr = 0xcccc;
+}
+
+#define SR_POLYNOM 0x8805
+static inline unsigned int compute_polynom(unsigned int sr)
+{
+ unsigned int i;
+ unsigned int f;
+
+ f = 0;
+ for (i = 0; i < 16; i++)
+ f += ((SR_POLYNOM >> i) & 1) & ((sr >> i) & 1);
+
+ return f;
+}
+
static inline int cris_mmu_enabled(uint32_t rw_gc_cfg)
{
return (rw_gc_cfg & 12) != 0;
@@ -152,11 +170,14 @@ static int cris_mmu_translate_page(struct cris_mmu_result_t *res,
hi = env->tlbsets[mmu][set][idx].hi;
tlb_vpn = EXTRACT_FIELD(hi, 13, 31);
+ tlb_pid = EXTRACT_FIELD(hi, 0, 7);
tlb_pfn = EXTRACT_FIELD(lo, 13, 31);
+ tlb_g = EXTRACT_FIELD(lo, 4, 4);
D(printf("TLB[%d][%d] v=%x vpage=%x -> pfn=%x lo=%x hi=%x\n",
i, idx, tlb_vpn, vpage, tlb_pfn, lo, hi));
- if (tlb_vpn == vpage) {
+ if ((tlb_g || (tlb_pid == (env->pregs[PR_PID] & 0xff)))
+ && tlb_vpn == vpage) {
match = 1;
break;
}
@@ -169,9 +190,7 @@ static int cris_mmu_translate_page(struct cris_mmu_result_t *res,
cfg_x = EXTRACT_FIELD(r_cfg, 17, 17);
cfg_v = EXTRACT_FIELD(r_cfg, 16, 16);
- tlb_pid = EXTRACT_FIELD(hi, 0, 7);
tlb_pfn = EXTRACT_FIELD(lo, 13, 31);
- tlb_g = EXTRACT_FIELD(lo, 4, 4);
tlb_v = EXTRACT_FIELD(lo, 3, 3);
tlb_k = EXTRACT_FIELD(lo, 2, 2);
tlb_w = EXTRACT_FIELD(lo, 1, 1);
@@ -187,13 +206,7 @@ static int cris_mmu_translate_page(struct cris_mmu_result_t *res,
set_exception_vector(0x0a, d_mmu_access);
set_exception_vector(0x0b, d_mmu_write);
*/
- if (!tlb_g
- && tlb_pid != (env->pregs[PR_PID] & 0xff)) {
- D(printf ("tlb: wrong pid %x %x pc=%x\n",
- tlb_pid, env->pregs[PR_PID], env->pc));
- match = 0;
- res->bf_vec = vect_base;
- } else if (cfg_k && tlb_k && usermode) {
+ if (cfg_k && tlb_k && usermode) {
D(printf ("tlb: kernel protected %x lo=%x pc=%x\n",
vaddr, lo, env->pc));
match = 0;
@@ -229,17 +242,27 @@ static int cris_mmu_translate_page(struct cris_mmu_result_t *res,
env->sregs[SFR_RW_MM_TLB_HI] = hi;
env->sregs[SFR_RW_MM_TLB_LO] = lo;
+ } else {
+ /* If refill, provide a randomized set. */
+ set = env->mmu_rand_lfsr & 3;
}
if (!match) {
- /* miss. */
+ unsigned int f;
+
+ /* Update lfsr at every fault. */
+ f = compute_polynom(env->mmu_rand_lfsr);
+ env->mmu_rand_lfsr >>= 1;
+ env->mmu_rand_lfsr |= (f << 15);
+ env->mmu_rand_lfsr &= 0xffff;
+
+ /* Compute index. */
idx = vpage & 15;
- set = 0;
/* Update RW_MM_TLB_SEL. */
env->sregs[SFR_RW_MM_TLB_SEL] = 0;
set_field(&env->sregs[SFR_RW_MM_TLB_SEL], idx, 0, 4);
- set_field(&env->sregs[SFR_RW_MM_TLB_SEL], set, 4, 5);
+ set_field(&env->sregs[SFR_RW_MM_TLB_SEL], set, 4, 2);
/* Update RW_MM_CAUSE. */
set_field(&r_cause, rwcause, 8, 2);