[SPARC64]: Fix setting of variables in LDOM guest.

There is a special domain services capability for setting
variables in the OBP options node.  Guests don't have permanent
store for the OBP variables like a normal system, so they are
instead maintained in the LDOM control node or in the SC.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 174 insertions, 13 deletions

diff --git a/arch/sparc64/kernel/ds.c b/arch/sparc64/kernel/ds.c
index 9c8839d1cffd..4e20ef232c51 100644
--- a/arch/sparc64/kernel/ds.c
+++ b/arch/sparc64/kernel/ds.c
@@ -11,6 +11,7 @@
 #include <linux/slab.h>
 #include <linux/sched.h>
 #include <linux/delay.h>
+#include <linux/mutex.h>
 
 #include <asm/ldc.h>
 #include <asm/vio.h>
@@ -171,7 +172,7 @@ static void md_update_data(struct ldc_channel *lp,
 
         rp = (struct ds_md_update_req *) (dpkt + 1);
 
-        printk(KERN_ERR PFX "Machine description update.\n");
+        printk(KERN_INFO PFX "Machine description update.\n");
 
         memset(&pkt, 0, sizeof(pkt));
         pkt.data.tag.type = DS_DATA;
@@ -248,8 +249,8 @@ static void domain_panic_data(struct ldc_channel *lp,
 
         rp = (struct ds_panic_req *) (dpkt + 1);
 
-        printk(KERN_ERR PFX "Panic REQ [%lx], len=%d\n",
-               rp->req_num, len);
+        printk(KERN_ALERT PFX "Panic request from "
+               "LDOM manager received.\n");
 
         memset(&pkt, 0, sizeof(pkt));
         pkt.data.tag.type = DS_DATA;
@@ -313,10 +314,60 @@ static void ds_pri_data(struct ldc_channel *lp,
 
         rp = (struct ds_pri_msg *) (dpkt + 1);
 
-        printk(KERN_ERR PFX "PRI REQ [%lx:%lx], len=%d\n",
+        printk(KERN_INFO PFX "PRI REQ [%lx:%lx], len=%d\n",
                rp->req_num, rp->type, len);
 }
 
+struct ds_var_hdr {
+        __u32                           type;
+#define DS_VAR_SET_REQ                  0x00
+#define DS_VAR_DELETE_REQ               0x01
+#define DS_VAR_SET_RESP                 0x02
+#define DS_VAR_DELETE_RESP              0x03
+};
+
+struct ds_var_set_msg {
+        struct ds_var_hdr               hdr;
+        char                            name_and_value[0];
+};
+
+struct ds_var_delete_msg {
+        struct ds_var_hdr               hdr;
+        char                            name[0];
+};
+
+struct ds_var_resp {
+        struct ds_var_hdr               hdr;
+        __u32                           result;
+#define DS_VAR_SUCCESS                  0x00
+#define DS_VAR_NO_SPACE                 0x01
+#define DS_VAR_INVALID_VAR              0x02
+#define DS_VAR_INVALID_VAL              0x03
+#define DS_VAR_NOT_PRESENT              0x04
+};
+
+static DEFINE_MUTEX(ds_var_mutex);
+static int ds_var_doorbell;
+static int ds_var_response;
+
+static void ds_var_data(struct ldc_channel *lp,
+                        struct ds_cap_state *dp,
+                        void *buf, int len)
+{
+        struct ds_data *dpkt = buf;
+        struct ds_var_resp *rp;
+
+        rp = (struct ds_var_resp *) (dpkt + 1);
+
+        if (rp->hdr.type != DS_VAR_SET_RESP &&
+            rp->hdr.type != DS_VAR_DELETE_RESP)
+                return;
+
+        ds_var_response = rp->result;
+        wmb();
+        ds_var_doorbell = 1;
+}
+
 struct ds_cap_state ds_states[] = {
         {
                 .service_id     = "md-update",
@@ -338,17 +389,16 @@ struct ds_cap_state ds_states[] = {
                 .service_id     = "pri",
                 .data           = ds_pri_data,
         },
+        {
+                .service_id     = "var-config",
+                .data           = ds_var_data,
+        },
+        {
+                .service_id     = "var-config-backup",
+                .data           = ds_var_data,
+        },
 };
 
-static struct ds_cap_state *find_cap(u64 handle)
-{
-        unsigned int index = handle >> 32;
-
-        if (index >= ARRAY_SIZE(ds_states))
-                return NULL;
-        return &ds_states[index];
-}
-
 static DEFINE_SPINLOCK(ds_lock);
 
 struct ds_info {
@@ -361,6 +411,115 @@ struct ds_info {
         int                     rcv_buf_len;
 };
 
+static struct ds_info *ds_info;
+
+static struct ds_cap_state *find_cap(u64 handle)
+{
+        unsigned int index = handle >> 32;
+
+        if (index >= ARRAY_SIZE(ds_states))
+                return NULL;
+        return &ds_states[index];
+}
+
+static struct ds_cap_state *find_cap_by_string(const char *name)
+{
+        int i;
+
+        for (i = 0; i < ARRAY_SIZE(ds_states); i++) {
+                if (strcmp(ds_states[i].service_id, name))
+                        continue;
+
+                return &ds_states[i];
+        }
+        return NULL;
+}
+
+void ldom_set_var(const char *var, const char *value)
+{
+        struct ds_info *dp = ds_info;
+        struct ds_cap_state *cp;
+
+        cp = find_cap_by_string("var-config");
+        if (cp->state != CAP_STATE_REGISTERED)
+                cp = find_cap_by_string("var-config-backup");
+
+        if (cp->state == CAP_STATE_REGISTERED) {
+                union {
+                        struct {
+                                struct ds_data          data;
+                                struct ds_var_set_msg   msg;
+                        } header;
+                        char                    all[512];
+                } pkt;
+                unsigned long flags;
+                char  *base, *p;
+                int msg_len, loops;
+
+                memset(&pkt, 0, sizeof(pkt));
+                pkt.header.data.tag.type = DS_DATA;
+                pkt.header.data.handle = cp->handle;
+                pkt.header.msg.hdr.type = DS_VAR_SET_REQ;
+                base = p = &pkt.header.msg.name_and_value[0];
+                strcpy(p, var);
+                p += strlen(var) + 1;
+                strcpy(p, value);
+                p += strlen(value) + 1;
+
+                msg_len = (sizeof(struct ds_data) +
+                               sizeof(struct ds_var_set_msg) +
+                               (p - base));
+                msg_len = (msg_len + 3) & ~3;
+                pkt.header.data.tag.len = msg_len - sizeof(struct ds_msg_tag);
+
+                mutex_lock(&ds_var_mutex);
+
+                spin_lock_irqsave(&ds_lock, flags);
+                ds_var_doorbell = 0;
+                ds_var_response = -1;
+
+                ds_send(dp->lp, &pkt, msg_len);
+                spin_unlock_irqrestore(&ds_lock, flags);
+
+                loops = 1000;
+                while (ds_var_doorbell == 0) {
+                        if (loops-- < 0)
+                                break;
+                        barrier();
+                        udelay(100);
+                }
+
+                mutex_unlock(&ds_var_mutex);
+
+                if (ds_var_doorbell == 0 ||
+                    ds_var_response != DS_VAR_SUCCESS)
+                        printk(KERN_ERR PFX "var-config [%s:%s] "
+                               "failed, response(%d).\n",
+                               var, value,
+                               ds_var_response);
+        } else {
+                printk(KERN_ERR PFX "var-config not registered so "
+                       "could not set (%s) variable to (%s).\n",
+                       var, value);
+        }
+}
+
+void ldom_reboot(const char *boot_command)
+{
+        /* Don't bother with any of this if the boot_command
+         * is empty.
+         */
+        if (boot_command && strlen(boot_command)) {
+                char full_boot_str[256];
+
+                strcpy(full_boot_str, "boot ");
+                strcpy(full_boot_str + strlen("boot "), boot_command);
+
+                ldom_set_var("reboot-command", full_boot_str);
+        }
+        sun4v_mach_sir();
+}
+
 static void ds_conn_reset(struct ds_info *dp)
 {
         printk(KERN_ERR PFX "ds_conn_reset() from %p\n",
@@ -594,6 +753,8 @@ static int __devinit ds_probe(struct vio_dev *vdev,
         if (err)
                 goto out_free_ldc;
 
+        ds_info = dp;
+
         start_powerd();
 
         return err;