[RFC/PATCH,v2,11/12] gunyah: Workarounds (NOT FOR MERGE)

Commit Message

Srivatsa Vaddagiri May 16, 2024, 2:33 p.m. UTC

These are some work-arounds required temporarily until some limitations
with Gunyah hypervisor are addressed.

Signed-off-by: Srivatsa Vaddagiri <[e-mail]>
---
 include/sysemu/gunyah_int.h |  1 +
 accel/gunyah/gunyah-all.c   | 18 ++++++++++++++++++
 hw/arm/boot.c               | 17 ++++++++++++++++-
 hw/arm/virt.c               |  3 ++-
 4 files changed, 37 insertions(+), 2 deletions(-)

Patch

diff --git a/include/sysemu/gunyah_int.h b/include/sysemu/gunyah_int.h
index ef82c6edd8..bdda430dbd 100644
--- a/include/sysemu/gunyah_int.h
+++ b/include/sysemu/gunyah_int.h
@@ -62,5 +62,6 @@  int gunyah_add_irqfd(int irqfd, int label, Error **errp);
 GUNYAHState *get_gunyah_state(void);
 int gunyah_arch_put_registers(CPUState *cs, int level);
 void gunyah_cpu_synchronize_post_reset(CPUState *cpu);
+gunyah_slot *gunyah_find_slot_by_addr(uint64_t addr);
 
 #endif    /* GUNYAH_INT_H */
diff --git a/accel/gunyah/gunyah-all.c b/accel/gunyah/gunyah-all.c
index 4c56dd8c73..bc106fbad6 100644
--- a/accel/gunyah/gunyah-all.c
+++ b/accel/gunyah/gunyah-all.c
@@ -158,6 +158,24 @@  static gunyah_slot *gunyah_find_overlap_slot(GUNYAHState *s,
     return NULL;
 }
 
+gunyah_slot *gunyah_find_slot_by_addr(uint64_t addr)
+{
+    GUNYAHState *s = GUNYAH_STATE(current_accel());
+    int i;
+    gunyah_slot *slot = NULL;
+
+    gunyah_slots_lock(s);
+    for (i = 0; i < s->nr_slots; ++i) {
+        slot = &s->slots[i];
+        if (slot->size &&
+            (addr >= slot->start && addr <= slot->start + slot->size))
+                break;
+    }
+    gunyah_slots_unlock(s);
+
+    return slot;
+}
+
 /* Called with s->slots_lock held */
 static gunyah_slot *gunyah_get_free_slot(GUNYAHState *s)
 {
diff --git a/hw/arm/boot.c b/hw/arm/boot.c
index 84ea6a807a..a29b2cb0f9 100644
--- a/hw/arm/boot.c
+++ b/hw/arm/boot.c
@@ -413,7 +413,8 @@  static int fdt_add_memory_node(void *fdt, uint32_t acells, hwaddr mem_base,
     char *nodename;
     int ret;
 
-    nodename = g_strdup_printf("/memory@%" PRIx64, mem_base);
+    /* Workaround until RM can parse memory nodes of type memory@XYZ. */
+    nodename = g_strdup_printf("/memory");
     qemu_fdt_add_subnode(fdt, nodename);
     qemu_fdt_setprop_string(fdt, nodename, "device_type", "memory");
     ret = qemu_fdt_setprop_sized_cells(fdt, nodename, "reg", acells, mem_base,
@@ -661,6 +662,20 @@  int arm_load_dtb(hwaddr addr, const struct arm_boot_info *binfo,
         binfo->modify_dtb(binfo, fdt);
     }
 
+    /*
+     * Gunyah RM inspects and modifies device-tree (to provide additional
+     * information that VM may need). It depends on knowing total size reserved
+     * for device-tree (i.e FDT_MAX_SIZE) and current size (via @totalsize). At
+     * this point however, @totalsize = FDT_MAX_SIZE, making RM think that there
+     * is no room for modification and fail to start VM.
+     *
+     * RM should ideally pack device-tree so that @totalsize reflects the actual
+     * size before it attempts modification. Until RM is fixed, pack
+     * device-tree so that @toalsize reflects the actual size.
+     */
+
+    fdt_pack(fdt);
+
     qemu_fdt_dumpdtb(fdt, size);
 
     /* Put the DTB into the memory map as a ROM image: this will ensure
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index b0132beddd..5f3075e748 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -188,7 +188,8 @@  static const MemMapEntry base_memmap[] = {
     [VIRT_PCIE_PIO] =           { 0x3eff0000, 0x00010000 },
     [VIRT_PCIE_ECAM] =          { 0x3f000000, 0x01000000 },
     /* Actual RAM size depends on initial RAM and device memory settings */
-    [VIRT_MEM] =                { GiB, LEGACY_RAMLIMIT_BYTES },
+    /* Workaround until Gunyah can accept mapping that starts from GiB */
+    [VIRT_MEM] =                { 2 * GiB, LEGACY_RAMLIMIT_BYTES },
 };
 
 /*