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-rw-r--r--arch/powerpc/platforms/powernv/ultravisor.c70
1 files changed, 70 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/ultravisor.c b/arch/powerpc/platforms/powernv/ultravisor.c
new file mode 100644
index 000000000..67c8c4b2d
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/ultravisor.c
@@ -0,0 +1,70 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Ultravisor high level interfaces
+ *
+ * Copyright 2019, IBM Corporation.
+ *
+ */
+#include <linux/init.h>
+#include <linux/printk.h>
+#include <linux/of_fdt.h>
+#include <linux/of.h>
+
+#include <asm/ultravisor.h>
+#include <asm/firmware.h>
+#include <asm/machdep.h>
+
+#include "powernv.h"
+
+static struct kobject *ultravisor_kobj;
+
+int __init early_init_dt_scan_ultravisor(unsigned long node, const char *uname,
+ int depth, void *data)
+{
+ if (!of_flat_dt_is_compatible(node, "ibm,ultravisor"))
+ return 0;
+
+ powerpc_firmware_features |= FW_FEATURE_ULTRAVISOR;
+ pr_debug("Ultravisor detected!\n");
+ return 1;
+}
+
+static struct memcons *uv_memcons;
+
+static ssize_t uv_msglog_read(struct file *file, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *to,
+ loff_t pos, size_t count)
+{
+ return memcons_copy(uv_memcons, to, pos, count);
+}
+
+static struct bin_attribute uv_msglog_attr = {
+ .attr = {.name = "msglog", .mode = 0400},
+ .read = uv_msglog_read
+};
+
+static int __init uv_init(void)
+{
+ struct device_node *node;
+
+ if (!firmware_has_feature(FW_FEATURE_ULTRAVISOR))
+ return 0;
+
+ node = of_find_compatible_node(NULL, NULL, "ibm,uv-firmware");
+ if (!node)
+ return -ENODEV;
+
+ uv_memcons = memcons_init(node, "memcons");
+ of_node_put(node);
+ if (!uv_memcons)
+ return -ENOENT;
+
+ uv_msglog_attr.size = memcons_get_size(uv_memcons);
+
+ ultravisor_kobj = kobject_create_and_add("ultravisor", firmware_kobj);
+ if (!ultravisor_kobj)
+ return -ENOMEM;
+
+ return sysfs_create_bin_file(ultravisor_kobj, &uv_msglog_attr);
+}
+machine_subsys_initcall(powernv, uv_init);