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-rw-r--r--target-arm/helper.c182
1 files changed, 182 insertions, 0 deletions
diff --git a/target-arm/helper.c b/target-arm/helper.c
index 9ff0771d50..541721807f 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -3,6 +3,7 @@
#include "helper.h"
#include "host-utils.h"
#include "sysemu.h"
+#include "bitops.h"
#ifndef CONFIG_USER_ONLY
static inline int get_phys_addr(CPUARMState *env, uint32_t address,
@@ -2184,6 +2185,184 @@ do_fault:
return code | (domain << 4);
}
+/* Fault type for long-descriptor MMU fault reporting; this corresponds
+ * to bits [5..2] in the STATUS field in long-format DFSR/IFSR.
+ */
+typedef enum {
+ translation_fault = 1,
+ access_fault = 2,
+ permission_fault = 3,
+} MMUFaultType;
+
+static int get_phys_addr_lpae(CPUARMState *env, uint32_t address,
+ int access_type, int is_user,
+ target_phys_addr_t *phys_ptr, int *prot,
+ target_ulong *page_size_ptr)
+{
+ /* Read an LPAE long-descriptor translation table. */
+ MMUFaultType fault_type = translation_fault;
+ uint32_t level = 1;
+ uint32_t epd;
+ uint32_t tsz;
+ uint64_t ttbr;
+ int ttbr_select;
+ int n;
+ target_phys_addr_t descaddr;
+ uint32_t tableattrs;
+ target_ulong page_size;
+ uint32_t attrs;
+
+ /* Determine whether this address is in the region controlled by
+ * TTBR0 or TTBR1 (or if it is in neither region and should fault).
+ * This is a Non-secure PL0/1 stage 1 translation, so controlled by
+ * TTBCR/TTBR0/TTBR1 in accordance with ARM ARM DDI0406C table B-32:
+ */
+ uint32_t t0sz = extract32(env->cp15.c2_control, 0, 3);
+ uint32_t t1sz = extract32(env->cp15.c2_control, 16, 3);
+ if (t0sz && !extract32(address, 32 - t0sz, t0sz)) {
+ /* there is a ttbr0 region and we are in it (high bits all zero) */
+ ttbr_select = 0;
+ } else if (t1sz && !extract32(~address, 32 - t1sz, t1sz)) {
+ /* there is a ttbr1 region and we are in it (high bits all one) */
+ ttbr_select = 1;
+ } else if (!t0sz) {
+ /* ttbr0 region is "everything not in the ttbr1 region" */
+ ttbr_select = 0;
+ } else if (!t1sz) {
+ /* ttbr1 region is "everything not in the ttbr0 region" */
+ ttbr_select = 1;
+ } else {
+ /* in the gap between the two regions, this is a Translation fault */
+ fault_type = translation_fault;
+ goto do_fault;
+ }
+
+ /* Note that QEMU ignores shareability and cacheability attributes,
+ * so we don't need to do anything with the SH, ORGN, IRGN fields
+ * in the TTBCR. Similarly, TTBCR:A1 selects whether we get the
+ * ASID from TTBR0 or TTBR1, but QEMU's TLB doesn't currently
+ * implement any ASID-like capability so we can ignore it (instead
+ * we will always flush the TLB any time the ASID is changed).
+ */
+ if (ttbr_select == 0) {
+ ttbr = ((uint64_t)env->cp15.c2_base0_hi << 32) | env->cp15.c2_base0;
+ epd = extract32(env->cp15.c2_control, 7, 1);
+ tsz = t0sz;
+ } else {
+ ttbr = ((uint64_t)env->cp15.c2_base1_hi << 32) | env->cp15.c2_base1;
+ epd = extract32(env->cp15.c2_control, 23, 1);
+ tsz = t1sz;
+ }
+
+ if (epd) {
+ /* Translation table walk disabled => Translation fault on TLB miss */
+ goto do_fault;
+ }
+
+ /* If the region is small enough we will skip straight to a 2nd level
+ * lookup. This affects the number of bits of the address used in
+ * combination with the TTBR to find the first descriptor. ('n' here
+ * matches the usage in the ARM ARM sB3.6.6, where bits [39..n] are
+ * from the TTBR, [n-1..3] from the vaddr, and [2..0] always zero).
+ */
+ if (tsz > 1) {
+ level = 2;
+ n = 14 - tsz;
+ } else {
+ n = 5 - tsz;
+ }
+
+ /* Clear the vaddr bits which aren't part of the within-region address,
+ * so that we don't have to special case things when calculating the
+ * first descriptor address.
+ */
+ address &= (0xffffffffU >> tsz);
+
+ /* Now we can extract the actual base address from the TTBR */
+ descaddr = extract64(ttbr, 0, 40);
+ descaddr &= ~((1ULL << n) - 1);
+
+ tableattrs = 0;
+ for (;;) {
+ uint64_t descriptor;
+
+ descaddr |= ((address >> (9 * (4 - level))) & 0xff8);
+ descriptor = ldq_phys(descaddr);
+ if (!(descriptor & 1) ||
+ (!(descriptor & 2) && (level == 3))) {
+ /* Invalid, or the Reserved level 3 encoding */
+ goto do_fault;
+ }
+ descaddr = descriptor & 0xfffffff000ULL;
+
+ if ((descriptor & 2) && (level < 3)) {
+ /* Table entry. The top five bits are attributes which may
+ * propagate down through lower levels of the table (and
+ * which are all arranged so that 0 means "no effect", so
+ * we can gather them up by ORing in the bits at each level).
+ */
+ tableattrs |= extract64(descriptor, 59, 5);
+ level++;
+ continue;
+ }
+ /* Block entry at level 1 or 2, or page entry at level 3.
+ * These are basically the same thing, although the number
+ * of bits we pull in from the vaddr varies.
+ */
+ page_size = (1 << (39 - (9 * level)));
+ descaddr |= (address & (page_size - 1));
+ /* Extract attributes from the descriptor and merge with table attrs */
+ attrs = extract64(descriptor, 2, 10)
+ | (extract64(descriptor, 52, 12) << 10);
+ attrs |= extract32(tableattrs, 0, 2) << 11; /* XN, PXN */
+ attrs |= extract32(tableattrs, 3, 1) << 5; /* APTable[1] => AP[2] */
+ /* The sense of AP[1] vs APTable[0] is reversed, as APTable[0] == 1
+ * means "force PL1 access only", which means forcing AP[1] to 0.
+ */
+ if (extract32(tableattrs, 2, 1)) {
+ attrs &= ~(1 << 4);
+ }
+ /* Since we're always in the Non-secure state, NSTable is ignored. */
+ break;
+ }
+ /* Here descaddr is the final physical address, and attributes
+ * are all in attrs.
+ */
+ fault_type = access_fault;
+ if ((attrs & (1 << 8)) == 0) {
+ /* Access flag */
+ goto do_fault;
+ }
+ fault_type = permission_fault;
+ if (is_user && !(attrs & (1 << 4))) {
+ /* Unprivileged access not enabled */
+ goto do_fault;
+ }
+ *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
+ if (attrs & (1 << 12) || (!is_user && (attrs & (1 << 11)))) {
+ /* XN or PXN */
+ if (access_type == 2) {
+ goto do_fault;
+ }
+ *prot &= ~PAGE_EXEC;
+ }
+ if (attrs & (1 << 5)) {
+ /* Write access forbidden */
+ if (access_type == 1) {
+ goto do_fault;
+ }
+ *prot &= ~PAGE_WRITE;
+ }
+
+ *phys_ptr = descaddr;
+ *page_size_ptr = page_size;
+ return 0;
+
+do_fault:
+ /* Long-descriptor format IFSR/DFSR value */
+ return (1 << 9) | (fault_type << 2) | level;
+}
+
static int get_phys_addr_mpu(CPUARMState *env, uint32_t address,
int access_type, int is_user,
target_phys_addr_t *phys_ptr, int *prot)
@@ -2287,6 +2466,9 @@ static inline int get_phys_addr(CPUARMState *env, uint32_t address,
*page_size = TARGET_PAGE_SIZE;
return get_phys_addr_mpu(env, address, access_type, is_user, phys_ptr,
prot);
+ } else if (extended_addresses_enabled(env)) {
+ return get_phys_addr_lpae(env, address, access_type, is_user, phys_ptr,
+ prot, page_size);
} else if (env->cp15.c1_sys & (1 << 23)) {
return get_phys_addr_v6(env, address, access_type, is_user, phys_ptr,
prot, page_size);