[Qemu-devel] [PATCH] PPC: Bamboo: Set initial TLB entry

[Alexander Graf <agraf@suse.de>]

Back in the day when the bamboo target got introduced, the initial TLB was
dictated by KVM. TCG has been missing initial TLB values ever since, rendering
the target unusable for TCG usage.

This patch adds linear TLB maps the way Linux expects them, making the target
work.

Signed-off-by: Alexander Graf <agraf@suse.de>
---
 hw/ppc440_bamboo.c |   27 ++++++++++++++++++++++++++-
 1 files changed, 26 insertions(+), 1 deletions(-)

diff --git a/hw/ppc440_bamboo.c b/hw/ppc440_bamboo.c
index f82d587..c17f6f7 100644
--- a/hw/ppc440_bamboo.c
+++ b/hw/ppc440_bamboo.c
@@ -103,6 +103,29 @@ out:
     return ret;
 }
 
+/* Create reset TLB entries for BookE, spanning the 32bit addr space.  */
+static void mmubooke_create_initial_mapping(CPUState *env,
+                                     target_ulong va,
+                                     target_phys_addr_t pa)
+{
+    ppcemb_tlb_t *tlb = &env->tlb.tlbe[0];
+
+    tlb->attr = 0;
+    tlb->prot = PAGE_VALID | ((PAGE_READ | PAGE_WRITE | PAGE_EXEC) << 4);
+    tlb->size = 1 << 31; /* up to 0x80000000  */
+    tlb->EPN = va & TARGET_PAGE_MASK;
+    tlb->RPN = pa & TARGET_PAGE_MASK;
+    tlb->PID = 0;
+
+    tlb = &env->tlb.tlbe[1];
+    tlb->attr = 0;
+    tlb->prot = PAGE_VALID | ((PAGE_READ | PAGE_WRITE | PAGE_EXEC) << 4);
+    tlb->size = 1 << 31; /* up to 0xffffffff  */
+    tlb->EPN = 0x80000000 & TARGET_PAGE_MASK;
+    tlb->RPN = 0x80000000 & TARGET_PAGE_MASK;
+    tlb->PID = 0;
+}
+
 static void main_cpu_reset(void *opaque)
 {
     CPUState *env = opaque;
@@ -111,6 +134,9 @@ static void main_cpu_reset(void *opaque)
     env->gpr[1] = (16<<20) - 8;
     env->gpr[3] = FDT_ADDR;
     env->nip = entry;
+
+    /* Create a mapping for the kernel.  */
+    mmubooke_create_initial_mapping(env, 0, 0);
 }
 
 static void bamboo_init(ram_addr_t ram_size,
@@ -181,7 +207,6 @@ static void bamboo_init(ram_addr_t ram_size,
             fprintf(stderr, "couldn't load device tree\n");
             exit(1);
         }
-        /* XXX we currently depend on KVM to create some initial TLB entries. */
     }
 
     if (kvm_enabled())
-- 
1.6.0.2