[Qemu-devel] [PATCH 1/5] target-ppc: Extend rtas-blob

[Aravinda Prasad <aravinda@linux.vnet.ibm.com>]

Extend rtas-blob to accommodate error log. Error log
structure is saved in rtas space upon a machine check
exception.

Signed-off-by: Aravinda Prasad <aravinda@linux.vnet.ibm.com>
---
 hw/ppc/spapr.c                  |   13 ++++++++++---
 hw/ppc/spapr_rtas.c             |    4 ++--
 include/hw/ppc/spapr.h          |    2 +-
 pc-bios/spapr-rtas/spapr-rtas.S |   12 ++++++++++++
 4 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index d01978f..1120988 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -85,6 +85,12 @@
 
 #define HTAB_SIZE(spapr)        (1ULL << ((spapr)->htab_shift))
 
+/*
+ * The rtas-entry-offset should match the value specified in
+ * spapr-rtas.S
+ */
+#define RTAS_ENTRY_OFFSET       0x1000
+
 typedef struct sPAPRMachineState sPAPRMachineState;
 
 #define TYPE_SPAPR_MACHINE      "spapr-machine"
@@ -670,7 +676,8 @@ static int spapr_populate_memory(sPAPREnvironment *spapr, void *fdt)
 static void spapr_finalize_fdt(sPAPREnvironment *spapr,
                                hwaddr fdt_addr,
                                hwaddr rtas_addr,
-                               hwaddr rtas_size)
+                               hwaddr rtas_size,
+                               hwaddr rtas_entry)
 {
     int ret, i;
     size_t cb = 0;
@@ -705,7 +712,7 @@ static void spapr_finalize_fdt(sPAPREnvironment *spapr,
     }
 
     /* RTAS */
-    ret = spapr_rtas_device_tree_setup(fdt, rtas_addr, rtas_size);
+    ret = spapr_rtas_device_tree_setup(fdt, rtas_addr, rtas_size, rtas_entry);
     if (ret < 0) {
         fprintf(stderr, "Couldn't set up RTAS device tree properties\n");
     }
@@ -808,7 +815,7 @@ static void ppc_spapr_reset(void)
 
     /* Load the fdt */
     spapr_finalize_fdt(spapr, spapr->fdt_addr, spapr->rtas_addr,
-                       spapr->rtas_size);
+                       spapr->rtas_size, spapr->rtas_addr + RTAS_ENTRY_OFFSET);
 
     /* Set up the entry state */
     first_ppc_cpu = POWERPC_CPU(first_cpu);
diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
index 9ba1ba6..02ddbf9 100644
--- a/hw/ppc/spapr_rtas.c
+++ b/hw/ppc/spapr_rtas.c
@@ -328,7 +328,7 @@ void spapr_rtas_register(int token, const char *name, spapr_rtas_fn fn)
 }
 
 int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
-                                 hwaddr rtas_size)
+                                 hwaddr rtas_size, hwaddr rtas_entry)
 {
     int ret;
     int i;
@@ -349,7 +349,7 @@ int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
     }
 
     ret = qemu_fdt_setprop_cell(fdt, "/rtas", "linux,rtas-entry",
-                                rtas_addr);
+                                rtas_entry);
     if (ret < 0) {
         fprintf(stderr, "Couldn't add linux,rtas-entry property: %s\n",
                 fdt_strerror(ret));
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index bbba51a..dedfa67 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -436,7 +436,7 @@ target_ulong spapr_rtas_call(PowerPCCPU *cpu, sPAPREnvironment *spapr,
                              uint32_t token, uint32_t nargs, target_ulong args,
                              uint32_t nret, target_ulong rets);
 int spapr_rtas_device_tree_setup(void *fdt, hwaddr rtas_addr,
-                                 hwaddr rtas_size);
+                                 hwaddr rtas_size, hwaddr rtas_entry);
 
 #define SPAPR_TCE_PAGE_SHIFT   12
 #define SPAPR_TCE_PAGE_SIZE    (1ULL << SPAPR_TCE_PAGE_SHIFT)
diff --git a/pc-bios/spapr-rtas/spapr-rtas.S b/pc-bios/spapr-rtas/spapr-rtas.S
index 903bec2..8c9b17e 100644
--- a/pc-bios/spapr-rtas/spapr-rtas.S
+++ b/pc-bios/spapr-rtas/spapr-rtas.S
@@ -30,6 +30,18 @@
 
 .globl	_start
 _start:
+	/*
+	 * Reserve space for error log in RTAS blob.
+	 *
+	 * Either we can reserve initial bytes for error log followed by
+	 * rtas-entry or space can be reserved after rtas-entry. I prefer
+	 * former, as we already have rtas-base and rtas-entry (currently
+	 * both pointing to rtas-base) defined in qemu and we can update
+	 * rtas-entry to point to an offset from rtas-base. This avoids
+	 * unnecessary definition of rtas-error-offset while keeping
+	 * rtas-entry redundant.
+	 */
+	. = 0x1000
 	mr	4,3
 	lis	3,KVMPPC_H_RTAS@h
 	ori	3,3,KVMPPC_H_RTAS@l