[POWERPC] pseries: phyp dump: Register dump area

Set up the actual dump header, register it with the hypervisor.

Signed-off-by: Manish Ahuja <mahuja@us.ibm.com>
Signed-off-by: Linas Vepstas <linasvepstas@gmail.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 131 insertions, 6 deletions

diff --git a/arch/powerpc/platforms/pseries/phyp_dump.c b/arch/powerpc/platforms/pseries/phyp_dump.c
index f355f052a56..d93f1b1585a 100644
--- a/arch/powerpc/platforms/pseries/phyp_dump.c
+++ b/arch/powerpc/platforms/pseries/phyp_dump.c
@@ -29,6 +29,117 @@
 static struct phyp_dump phyp_dump_vars;
 struct phyp_dump *phyp_dump_info = &phyp_dump_vars;
 
+static int ibm_configure_kernel_dump;
+/* ------------------------------------------------- */
+/* RTAS interfaces to declare the dump regions */
+
+struct dump_section {
+        u32 dump_flags;
+        u16 source_type;
+        u16 error_flags;
+        u64 source_address;
+        u64 source_length;
+        u64 length_copied;
+        u64 destination_address;
+};
+
+struct phyp_dump_header {
+        u32 version;
+        u16 num_of_sections;
+        u16 status;
+
+        u32 first_offset_section;
+        u32 dump_disk_section;
+        u64 block_num_dd;
+        u64 num_of_blocks_dd;
+        u32 offset_dd;
+        u32 maxtime_to_auto;
+        /* No dump disk path string used */
+
+        struct dump_section cpu_data;
+        struct dump_section hpte_data;
+        struct dump_section kernel_data;
+};
+
+/* The dump header *must be* in low memory, so .bss it */
+static struct phyp_dump_header phdr;
+
+#define NUM_DUMP_SECTIONS       3
+#define DUMP_HEADER_VERSION     0x1
+#define DUMP_REQUEST_FLAG       0x1
+#define DUMP_SOURCE_CPU         0x0001
+#define DUMP_SOURCE_HPTE        0x0002
+#define DUMP_SOURCE_RMO         0x0011
+
+/**
+ * init_dump_header() - initialize the header declaring a dump
+ * Returns: length of dump save area.
+ *
+ * When the hypervisor saves crashed state, it needs to put
+ * it somewhere. The dump header tells the hypervisor where
+ * the data can be saved.
+ */
+static unsigned long init_dump_header(struct phyp_dump_header *ph)
+{
+        unsigned long addr_offset = 0;
+
+        /* Set up the dump header */
+        ph->version = DUMP_HEADER_VERSION;
+        ph->num_of_sections = NUM_DUMP_SECTIONS;
+        ph->status = 0;
+
+        ph->first_offset_section =
+                (u32)offsetof(struct phyp_dump_header, cpu_data);
+        ph->dump_disk_section = 0;
+        ph->block_num_dd = 0;
+        ph->num_of_blocks_dd = 0;
+        ph->offset_dd = 0;
+
+        ph->maxtime_to_auto = 0; /* disabled */
+
+        /* The first two sections are mandatory */
+        ph->cpu_data.dump_flags = DUMP_REQUEST_FLAG;
+        ph->cpu_data.source_type = DUMP_SOURCE_CPU;
+        ph->cpu_data.source_address = 0;
+        ph->cpu_data.source_length = phyp_dump_info->cpu_state_size;
+        ph->cpu_data.destination_address = addr_offset;
+        addr_offset += phyp_dump_info->cpu_state_size;
+
+        ph->hpte_data.dump_flags = DUMP_REQUEST_FLAG;
+        ph->hpte_data.source_type = DUMP_SOURCE_HPTE;
+        ph->hpte_data.source_address = 0;
+        ph->hpte_data.source_length = phyp_dump_info->hpte_region_size;
+        ph->hpte_data.destination_address = addr_offset;
+        addr_offset += phyp_dump_info->hpte_region_size;
+
+        /* This section describes the low kernel region */
+        ph->kernel_data.dump_flags = DUMP_REQUEST_FLAG;
+        ph->kernel_data.source_type = DUMP_SOURCE_RMO;
+        ph->kernel_data.source_address = PHYP_DUMP_RMR_START;
+        ph->kernel_data.source_length = PHYP_DUMP_RMR_END;
+        ph->kernel_data.destination_address = addr_offset;
+        addr_offset += ph->kernel_data.source_length;
+
+        return addr_offset;
+}
+
+static void register_dump_area(struct phyp_dump_header *ph, unsigned long addr)
+{
+        int rc;
+        ph->cpu_data.destination_address += addr;
+        ph->hpte_data.destination_address += addr;
+        ph->kernel_data.destination_address += addr;
+
+        do {
+                rc = rtas_call(ibm_configure_kernel_dump, 3, 1, NULL,
+                                1, ph, sizeof(struct phyp_dump_header));
+        } while (rtas_busy_delay(rc));
+
+        if (rc)
+                printk(KERN_ERR "phyp-dump: unexpected error (%d) on "
+                                                "register\n", rc);
+}
+
 /* ------------------------------------------------- */
 /**
  * release_memory_range -- release memory previously lmb_reserved
@@ -107,7 +218,9 @@ static struct kobj_attribute rr = __ATTR(release_region, 0600,
 static int __init phyp_dump_setup(void)
 {
         struct device_node *rtas;
-        const int *dump_header = NULL;
+        const struct phyp_dump_header *dump_header = NULL;
+        unsigned long dump_area_start;
+        unsigned long dump_area_length;
         int header_len = 0;
         int rc;
 
@@ -119,7 +232,13 @@ static int __init phyp_dump_setup(void)
         if (!phyp_dump_info->phyp_dump_configured)
                 return -ENOSYS;
 
-        /* Is there dump data waiting for us? */
+        /* Is there dump data waiting for us? If there isn't,
+         * then register a new dump area, and release all of
+         * the rest of the reserved ram.
+         *
+         * The /rtas/ibm,kernel-dump rtas node is present only
+         * if there is dump data waiting for us.
+         */
         rtas = of_find_node_by_path("/rtas");
         if (rtas) {
                 dump_header = of_get_property(rtas, "ibm,kernel-dump",
@@ -127,17 +246,23 @@ static int __init phyp_dump_setup(void)
                 of_node_put(rtas);
         }
 
-        if (dump_header == NULL)
+        dump_area_length = init_dump_header(&phdr);
+
+        /* align down */
+        dump_area_start = phyp_dump_info->init_reserve_start & PAGE_MASK;
+
+        if (dump_header == NULL) {
+                register_dump_area(&phdr, dump_area_start);
                 return 0;
+        }
 
         /* Should we create a dump_subsys, analogous to s390/ipl.c ? */
         rc = sysfs_create_file(kernel_kobj, &rr.attr);
-        if (rc) {
+        if (rc)
                 printk(KERN_ERR "phyp-dump: unable to create sysfs file (%d)\n",
                                                                         rc);
-                return 0;
-        }
 
+        /* ToDo: re-register the dump area, for next time. */
         return 0;
 }
 machine_subsys_initcall(pseries, phyp_dump_setup);