Implement the optional segmentation control feature in the virtual to
physical address translation code.
The fixed legacy segment and XKPhys handling is replaced with a dynamic
layout based on the segmentation control registers (which should be set
up even when the feature is not exposed to the guest).
Signed-off-by: James Hogan <james.ho...@imgtec.com>
Cc: Leon Alrae <leon.al...@imgtec.com>
Cc: Aurelien Jarno <aurel...@aurel32.net>
---
target-mips/helper.c | 154 +++++++++++++++++++++++++++++++++++---------
1 file changed, 123 insertions(+), 31 deletions(-)
diff --git a/target-mips/helper.c b/target-mips/helper.c
index 2065fc3ec119..63d709bd620f 100644
--- a/target-mips/helper.c
+++ b/target-mips/helper.c
@@ -107,15 +107,107 @@ int r4k_map_address (CPUMIPSState *env, hwaddr
*physical, int *prot,
return TLBRET_NOMATCH;
}
+static int is_seg_am_mapped(unsigned int am, bool eu, int mmu_idx)
+{
+ /*
+ * Interpret access control mode and mmu_idx.
+ * AdE? TLB?
+ * AM K S U E K S U E
+ * UK 0 0 1 1 0 0 - - 0
+ * MK 1 0 1 1 0 1 - - !eu
+ * MSK 2 0 0 1 0 1 1 - !eu
+ * MUSK 3 0 0 0 0 1 1 1 !eu
+ * MUSUK 4 0 0 0 0 0 1 1 0
+ * USK 5 0 0 1 0 0 0 - 0
+ * - 6 - - - - - - - -
+ * UUSK 7 0 0 0 0 0 0 0 0
+ */
+ int32_t adetlb_mask;
+
+ switch (mmu_idx) {
+ case 3 /* ERL */:
+ /* If EU is set, always unmapped */
+ if (eu) {
+ return 0;
+ }
+ /* fall through */
+ case MIPS_HFLAG_KM:
+ /* Never AdE, TLB mapped if AM={1,2,3} */
+ adetlb_mask = 0x70000000;
+ goto check_tlb;
+
+ case MIPS_HFLAG_SM:
+ /* AdE if AM={0,1}, TLB mapped if AM={2,3,4} */
+ adetlb_mask = 0xc0380000;
+ goto check_ade;
+
+ case MIPS_HFLAG_UM:
+ /* AdE if AM={0,1,2,5}, TLB mapped if AM={3,4} */
+ adetlb_mask = 0xe4180000;
+ /* fall through */
+ check_ade:
+ /* does this AM cause AdE in current execution mode */
+ if ((adetlb_mask << am) < 0) {
+ return TLBRET_BADADDR;
+ }
+ adetlb_mask <<= 8;
+ /* fall through */
+ check_tlb:
+ /* is this AM mapped in current execution mode */
+ return ((adetlb_mask << am) < 0);
+ default:
+ assert(0);
+ return TLBRET_BADADDR;
+ };
+}
+
+static int get_seg_physical_address(CPUMIPSState *env, hwaddr *physical,
+ int *prot, target_ulong real_address,
+ int rw, int access_type, int mmu_idx,
+ unsigned int am, bool eu,
+ target_ulong segmask,
+ target_ulong physical_base)
+{
+ int mapped = is_seg_am_mapped(am, eu, mmu_idx);
+
+ if (mapped < 0) {
+ /* is_seg_am_mapped can report TLBRET_BADADDR */
+ return mapped;
+ } else if (mapped) {
+ /* The segment is TLB mapped */
+ return env->tlb->map_address(env, physical, prot, real_address, rw,
+ access_type);
+ } else {
+ /* The segment is unmapped */
+ *physical = physical_base | (real_address & segmask);
+ *prot = PAGE_READ | PAGE_WRITE;
+ return TLBRET_MATCH;
+ }
+}
+
+static int get_segctl_physical_address(CPUMIPSState *env, hwaddr *physical,
+ int *prot, target_ulong real_address,
+ int rw, int access_type, int mmu_idx,
+ uint16_t segctl, target_ulong segmask)
+{
+ unsigned int am = (segctl & CP0SC_AM_MASK) >> CP0SC_AM;
+ bool eu = (segctl >> CP0SC_EU) & 1;
+ target_ulong pa = ((target_ulong)segctl & CP0SC_PA_MASK) << 20;
+
+ return get_seg_physical_address(env, physical, prot, real_address, rw,
+ access_type, mmu_idx, am, eu, segmask,
+ pa & ~segmask);
+}
+
static int get_physical_address (CPUMIPSState *env, hwaddr *physical,
int *prot, target_ulong real_address,
int rw, int access_type, int mmu_idx)
{
/* User mode can only access useg/xuseg */
+#if defined(TARGET_MIPS64)
int user_mode = mmu_idx == MIPS_HFLAG_UM;
int supervisor_mode = mmu_idx == MIPS_HFLAG_SM;
int kernel_mode = !user_mode && !supervisor_mode;
-#if defined(TARGET_MIPS64)
int UX = (env->CP0_Status & (1 << CP0St_UX)) != 0;
int SX = (env->CP0_Status & (1 << CP0St_SX)) != 0;
int KX = (env->CP0_Status & (1 << CP0St_KX)) != 0;
@@ -148,12 +240,16 @@ static int get_physical_address (CPUMIPSState *env,
hwaddr *physical,
if (address <= USEG_LIMIT) {
/* useg */
- if (env->CP0_Status & (1 << CP0St_ERL)) {
- *physical = address & 0xFFFFFFFF;
- *prot = PAGE_READ | PAGE_WRITE;
+ uint16_t segctl;
+
+ if (address >= 0x40000000UL) {
+ segctl = env->CP0_SegCtl2;
} else {
- ret = env->tlb->map_address(env, physical, prot, real_address, rw,
access_type);
+ segctl = env->CP0_SegCtl2 >> 16;
}
+ ret = get_segctl_physical_address(env, physical, prot, real_address,
rw,
+ access_type, mmu_idx, segctl,
+ 0x3FFFFFFF);
#if defined(TARGET_MIPS64)
} else if (address < 0x4000000000000000ULL) {
/* xuseg */
@@ -172,10 +268,16 @@ static int get_physical_address (CPUMIPSState *env,
hwaddr *physical,
}
} else if (address < 0xC000000000000000ULL) {
/* xkphys */
- if (kernel_mode && KX &&
- (address & 0x07FFFFFFFFFFFFFFULL) <= env->PAMask) {
- *physical = address & env->PAMask;
- *prot = PAGE_READ | PAGE_WRITE;
+ if (KX && (address & 0x07FFFFFFFFFFFFFFULL) <= env->PAMask) {
+ unsigned int am = CP0SC_AM_UK;
+ unsigned int xr = (env->CP0_SegCtl2 & CP0SC2_XR_MASK) >> CP0SC2_XR;
+
+ if (xr & (1 << ((address >> 59) & 0x7))) {
+ am = (env->CP0_SegCtl1 & CP0SC1_XAM_MASK) >> CP0SC1_XAM;
+ }
+ ret = get_seg_physical_address(env, physical, prot, real_address,
+ rw, access_type, mmu_idx, am, false,
+ env->PAMask, 0);
} else {
ret = TLBRET_BADADDR;
}
@@ -190,35 +292,25 @@ static int get_physical_address (CPUMIPSState *env,
hwaddr *physical,
#endif
} else if (address < (int32_t)KSEG1_BASE) {
/* kseg0 */
- if (kernel_mode) {
- *physical = address - (int32_t)KSEG0_BASE;
- *prot = PAGE_READ | PAGE_WRITE;
- } else {
- ret = TLBRET_BADADDR;
- }
+ ret = get_segctl_physical_address(env, physical, prot, real_address,
rw,
+ access_type, mmu_idx,
+ env->CP0_SegCtl1 >> 16, 0x1FFFFFFF);
} else if (address < (int32_t)KSEG2_BASE) {
/* kseg1 */
- if (kernel_mode) {
- *physical = address - (int32_t)KSEG1_BASE;
- *prot = PAGE_READ | PAGE_WRITE;
- } else {
- ret = TLBRET_BADADDR;
- }
+ ret = get_segctl_physical_address(env, physical, prot, real_address,
rw,
+ access_type, mmu_idx,
+ env->CP0_SegCtl1, 0x1FFFFFFF);
} else if (address < (int32_t)KSEG3_BASE) {
/* sseg (kseg2) */
- if (supervisor_mode || kernel_mode) {
- ret = env->tlb->map_address(env, physical, prot, real_address, rw,
access_type);
- } else {
- ret = TLBRET_BADADDR;
- }
+ ret = get_segctl_physical_address(env, physical, prot, real_address,
rw,
+ access_type, mmu_idx,
+ env->CP0_SegCtl0 >> 16, 0x1FFFFFFF);
} else {
/* kseg3 */
/* XXX: debug segment is not emulated */
- if (kernel_mode) {
- ret = env->tlb->map_address(env, physical, prot, real_address, rw,
access_type);
- } else {
- ret = TLBRET_BADADDR;
- }
+ ret = get_segctl_physical_address(env, physical, prot, real_address,
rw,
+ access_type, mmu_idx,
+ env->CP0_SegCtl0, 0x1FFFFFFF);
}
return ret;
}
--
git-series 0.8.10
