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authorPeter Maydell <peter.maydell@linaro.org>2015-04-13 13:50:30 +0100
committerPeter Maydell <peter.maydell@linaro.org>2015-04-13 13:50:30 +0100
commit85ae0d5c657d3cb04eb3f86f00feda9157a81645 (patch)
tree402af9d430f11e956f8220ae936805cae8cf2ce6
parent30506ad12ad6a2bc83bfcfd8cd9bc8b1bfe51ffd (diff)
downloadqemu-arm-85ae0d5c657d3cb04eb3f86f00feda9157a81645.tar.gz
target-arm: Use correct memory attributes for page table walks
Factor out the page table walk memory accesses into their own function, so that we can specify the correct S/NS memory attributes for them. This will also provide a place to use the correct endianness and handle the need for a stage-2 translation when virtualization is supported. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
-rw-r--r--target-arm/helper.c49
1 files changed, 40 insertions, 9 deletions
diff --git a/target-arm/helper.c b/target-arm/helper.c
index a568299cc6..a01ff7fccc 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -5129,6 +5129,29 @@ static bool get_level1_table_address(CPUARMState *env, ARMMMUIdx mmu_idx,
return true;
}
+/* All loads done in the course of a page table walk go through here.
+ * TODO: rather than ignoring errors from physical memory reads (which
+ * are external aborts in ARM terminology) we should propagate this
+ * error out so that we can turn it into a Data Abort if this walk
+ * was being done for a CPU load/store or an address translation instruction
+ * (but not if it was for a debug access).
+ */
+static uint32_t arm_ldl_ptw(CPUState *cs, hwaddr addr, bool is_secure)
+{
+ MemTxAttrs attrs = {};
+
+ attrs.secure = is_secure;
+ return address_space_ldl(cs->as, addr, attrs, NULL);
+}
+
+static uint64_t arm_ldq_ptw(CPUState *cs, hwaddr addr, bool is_secure)
+{
+ MemTxAttrs attrs = {};
+
+ attrs.secure = is_secure;
+ return address_space_ldq(cs->as, addr, attrs, NULL);
+}
+
static int get_phys_addr_v5(CPUARMState *env, uint32_t address, int access_type,
ARMMMUIdx mmu_idx, hwaddr *phys_ptr,
int *prot, target_ulong *page_size)
@@ -5151,7 +5174,7 @@ static int get_phys_addr_v5(CPUARMState *env, uint32_t address, int access_type,
code = 5;
goto do_fault;
}
- desc = ldl_phys(cs->as, table);
+ desc = arm_ldl_ptw(cs, table, regime_is_secure(env, mmu_idx));
type = (desc & 3);
domain = (desc >> 5) & 0x0f;
if (regime_el(env, mmu_idx) == 1) {
@@ -5187,7 +5210,7 @@ static int get_phys_addr_v5(CPUARMState *env, uint32_t address, int access_type,
/* Fine pagetable. */
table = (desc & 0xfffff000) | ((address >> 8) & 0xffc);
}
- desc = ldl_phys(cs->as, table);
+ desc = arm_ldl_ptw(cs, table, regime_is_secure(env, mmu_idx));
switch (desc & 3) {
case 0: /* Page translation fault. */
code = 7;
@@ -5261,7 +5284,7 @@ static int get_phys_addr_v6(CPUARMState *env, uint32_t address, int access_type,
code = 5;
goto do_fault;
}
- desc = ldl_phys(cs->as, table);
+ desc = arm_ldl_ptw(cs, table, regime_is_secure(env, mmu_idx));
type = (desc & 3);
if (type == 0 || (type == 3 && !arm_feature(env, ARM_FEATURE_PXN))) {
/* Section translation fault, or attempt to use the encoding
@@ -5310,7 +5333,7 @@ static int get_phys_addr_v6(CPUARMState *env, uint32_t address, int access_type,
ns = extract32(desc, 3, 1);
/* Lookup l2 entry. */
table = (desc & 0xfffffc00) | ((address >> 10) & 0x3fc);
- desc = ldl_phys(cs->as, table);
+ desc = arm_ldl_ptw(cs, table, regime_is_secure(env, mmu_idx));
ap = ((desc >> 4) & 3) | ((desc >> 7) & 4);
switch (desc & 3) {
case 0: /* Page translation fault. */
@@ -5525,13 +5548,20 @@ static int get_phys_addr_lpae(CPUARMState *env, target_ulong address,
descaddr = extract64(ttbr, 0, 48);
descaddr &= ~((1ULL << (va_size - tsz - (granule_sz * (4 - level)))) - 1);
- tableattrs = 0;
+ /* Secure accesses start with the page table in secure memory and
+ * can be downgraded to non-secure at any step. Non-secure accesses
+ * remain non-secure. We implement this by just ORing in the NSTable/NS
+ * bits at each step.
+ */
+ tableattrs = regime_is_secure(env, mmu_idx) ? 0 : (1 << 4);
for (;;) {
uint64_t descriptor;
+ bool nstable;
descaddr |= (address >> (granule_sz * (4 - level))) & descmask;
descaddr &= ~7ULL;
- descriptor = ldq_phys(cs->as, descaddr);
+ nstable = extract32(tableattrs, 4, 1);
+ descriptor = arm_ldq_ptw(cs, descaddr, !nstable);
if (!(descriptor & 1) ||
(!(descriptor & 2) && (level == 3))) {
/* Invalid, or the Reserved level 3 encoding */
@@ -5566,7 +5596,7 @@ static int get_phys_addr_lpae(CPUARMState *env, target_ulong address,
if (extract32(tableattrs, 2, 1)) {
attrs &= ~(1 << 4);
}
- attrs |= extract32(tableattrs, 4, 1) << 3; /* NS */
+ attrs |= nstable << 3; /* NS */
break;
}
/* Here descaddr is the final physical address, and attributes
@@ -5705,8 +5735,9 @@ static inline int get_phys_addr(CPUARMState *env, target_ulong address,
{
if (mmu_idx == ARMMMUIdx_S12NSE0 || mmu_idx == ARMMMUIdx_S12NSE1) {
/* TODO: when we support EL2 we should here call ourselves recursively
- * to do the stage 1 and then stage 2 translations. The ldl_phys
- * calls for stage 1 will also need changing.
+ * to do the stage 1 and then stage 2 translations. The arm_ld*_ptw
+ * functions will also need changing to perform ARMMMUIdx_S2NS loads
+ * rather than direct physical memory loads when appropriate.
* For non-EL2 CPUs a stage1+stage2 translation is just stage 1.
*/
assert(!arm_feature(env, ARM_FEATURE_EL2));