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Diffstat (limited to 'arch/powerpc/platforms/powernv/opal.c')
-rw-r--r--arch/powerpc/platforms/powernv/opal.c154
1 files changed, 154 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
new file mode 100644
index 00000000000..8d5510784cc
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -0,0 +1,154 @@
+/*
+ * PowerNV OPAL high level interfaces
+ *
+ * Copyright 2011 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#undef DEBUG
+
+#include <linux/types.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <asm/opal.h>
+#include <asm/firmware.h>
+
+#include "powernv.h"
+
+struct opal {
+ u64 base;
+ u64 entry;
+} opal;
+
+static struct device_node *opal_node;
+static DEFINE_SPINLOCK(opal_write_lock);
+
+int __init early_init_dt_scan_opal(unsigned long node,
+ const char *uname, int depth, void *data)
+{
+ const void *basep, *entryp;
+ unsigned long basesz, entrysz;
+
+ if (depth != 1 || strcmp(uname, "ibm,opal") != 0)
+ return 0;
+
+ basep = of_get_flat_dt_prop(node, "opal-base-address", &basesz);
+ entryp = of_get_flat_dt_prop(node, "opal-entry-address", &entrysz);
+
+ if (!basep || !entryp)
+ return 1;
+
+ opal.base = of_read_number(basep, basesz/4);
+ opal.entry = of_read_number(entryp, entrysz/4);
+
+ pr_debug("OPAL Base = 0x%llx (basep=%p basesz=%ld)\n",
+ opal.base, basep, basesz);
+ pr_debug("OPAL Entry = 0x%llx (entryp=%p basesz=%ld)\n",
+ opal.entry, entryp, entrysz);
+
+ powerpc_firmware_features |= FW_FEATURE_OPAL;
+ if (of_flat_dt_is_compatible(node, "ibm,opal-v2")) {
+ powerpc_firmware_features |= FW_FEATURE_OPALv2;
+ printk("OPAL V2 detected !\n");
+ } else {
+ printk("OPAL V1 detected !\n");
+ }
+
+ return 1;
+}
+
+int opal_get_chars(uint32_t vtermno, char *buf, int count)
+{
+ s64 len, rc;
+ u64 evt;
+
+ if (!opal.entry)
+ return 0;
+ opal_poll_events(&evt);
+ if ((evt & OPAL_EVENT_CONSOLE_INPUT) == 0)
+ return 0;
+ len = count;
+ rc = opal_console_read(vtermno, &len, buf);
+ if (rc == OPAL_SUCCESS)
+ return len;
+ return 0;
+}
+
+int opal_put_chars(uint32_t vtermno, const char *data, int total_len)
+{
+ int written = 0;
+ s64 len, rc = OPAL_BUSY;
+ unsigned long flags;
+ u64 evt;
+
+ if (!opal.entry)
+ return 0;
+
+ /* We want put_chars to be atomic to avoid mangling of hvsi
+ * packets. To do that, we first test for room and return
+ * -EAGAIN if there isn't enough
+ */
+ spin_lock_irqsave(&opal_write_lock, flags);
+ rc = opal_console_write_buffer_space(vtermno, &len);
+ if (rc || len < total_len) {
+ spin_unlock_irqrestore(&opal_write_lock, flags);
+ /* Closed -> drop characters */
+ if (rc)
+ return total_len;
+ opal_poll_events(&evt);
+ return -EAGAIN;
+ }
+
+ /* We still try to handle partial completions, though they
+ * should no longer happen.
+ */
+ while(total_len > 0 && (rc == OPAL_BUSY ||
+ rc == OPAL_BUSY_EVENT || rc == OPAL_SUCCESS)) {
+ len = total_len;
+ rc = opal_console_write(vtermno, &len, data);
+ if (rc == OPAL_SUCCESS) {
+ total_len -= len;
+ data += len;
+ written += len;
+ }
+ /* This is a bit nasty but we need that for the console to
+ * flush when there aren't any interrupts. We will clean
+ * things a bit later to limit that to synchronous path
+ * such as the kernel console and xmon/udbg
+ */
+ do
+ opal_poll_events(&evt);
+ while(rc == OPAL_SUCCESS && (evt & OPAL_EVENT_CONSOLE_OUTPUT));
+ }
+ spin_unlock_irqrestore(&opal_write_lock, flags);
+ return written;
+}
+
+static int __init opal_init(void)
+{
+ struct device_node *np, *consoles;
+
+ opal_node = of_find_node_by_path("/ibm,opal");
+ if (!opal_node) {
+ pr_warn("opal: Node not found\n");
+ return -ENODEV;
+ }
+ if (firmware_has_feature(FW_FEATURE_OPALv2))
+ consoles = of_find_node_by_path("/ibm,opal/consoles");
+ else
+ consoles = of_node_get(opal_node);
+
+ /* Register serial ports */
+ for_each_child_of_node(consoles, np) {
+ if (strcmp(np->name, "serial"))
+ continue;
+ of_platform_device_create(np, NULL, NULL);
+ }
+ of_node_put(consoles);
+ return 0;
+}
+subsys_initcall(opal_init);