[Skiboot] [PATCH 1/2] mambo: Add Fake NVRAM driver

[Jack Miller]

Implement a fake NVRAM device based on arbitrary memory reserves.
This allows NVRAM images to be preloaded without the FSP.

Signed-off-by: Jack Miller <jack at codezen.org>
Tested-by: Chris Smart <chris at distroguy.com>
---
 core/platform.c   |  3 +++
 hw/Makefile.inc   |  1 +
 hw/fake-nvram.c   | 62 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 include/skiboot.h |  5 +++++
 4 files changed, 71 insertions(+)
 create mode 100644 hw/fake-nvram.c

diff --git a/core/platform.c b/core/platform.c
index ba0636d942426138..4e1c69144d541a59 100644
--- a/core/platform.c
+++ b/core/platform.c
@@ -136,6 +136,9 @@ static struct platform generic_platform = {
 	.bmc		= &generic_bmc,
 	.probe          = generic_platform_probe,
 	.init		= generic_platform_init,
+	.nvram_info	= fake_nvram_info,
+	.nvram_start_read = fake_nvram_start_read,
+	.nvram_write	= fake_nvram_write,
 	.cec_power_down	= generic_cec_power_down,
 };
 
diff --git a/hw/Makefile.inc b/hw/Makefile.inc
index a433c2b6fefc91ec..f2dc328e85ab64f6 100644
--- a/hw/Makefile.inc
+++ b/hw/Makefile.inc
@@ -6,6 +6,7 @@ HW_OBJS += nx.o nx-rng.o nx-crypto.o nx-842.o
 HW_OBJS += p7ioc.o p7ioc-inits.o p7ioc-phb.o
 HW_OBJS += phb3.o sfc-ctrl.o fake-rtc.o bt.o p8-i2c.o prd.o
 HW_OBJS += dts.o lpc-rtc.o npu.o npu-hw-procedures.o xive.o phb4.o
+HW_OBJS += fake-nvram.o
 HW=hw/built-in.o
 
 # FIXME hack this for now
diff --git a/hw/fake-nvram.c b/hw/fake-nvram.c
new file mode 100644
index 0000000000000000..99bee9fb4879e0b4
--- /dev/null
+++ b/hw/fake-nvram.c
@@ -0,0 +1,62 @@
+/* Copyright 2013-2014 IBM Corp.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * 	http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ * implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <skiboot.h>
+#include <opal.h>
+#include <mem_region.h>
+#include <lock.h>
+
+static struct mem_region *nvram_region = NULL;
+static struct lock fake_nvram_lock = LOCK_UNLOCKED;
+
+int fake_nvram_info(uint32_t *total_size)
+{
+	nvram_region = find_mem_region("ibm,fake-nvram");
+
+	if(!nvram_region)
+		return OPAL_HARDWARE;
+
+	*total_size = nvram_region->len;
+
+	return OPAL_SUCCESS;
+}
+
+int fake_nvram_start_read(void *dst, uint32_t src, uint32_t len)
+{
+	if(!nvram_region)
+		return -ENODEV;
+
+	lock(&fake_nvram_lock);
+	memcpy(dst, (void *) (nvram_region->start + src), len);
+	unlock(&fake_nvram_lock);
+
+	nvram_read_complete(true);
+
+	return 0;
+}
+
+int fake_nvram_write(uint32_t offset, void *src, uint32_t size)
+{
+	if(!nvram_region)
+		return OPAL_HARDWARE;
+
+	lock(&fake_nvram_lock);
+	memcpy((void *) (nvram_region->start + offset), src, size);
+	unlock(&fake_nvram_lock);
+
+	return 0;
+}
+
diff --git a/include/skiboot.h b/include/skiboot.h
index 3f7c077812ed782b..2ea64de36bd1ed6b 100644
--- a/include/skiboot.h
+++ b/include/skiboot.h
@@ -292,4 +292,9 @@ extern void enter_pm_state(bool winkle);
 extern uint32_t reset_patch_start;
 extern uint32_t reset_patch_end;
 
+/* Fallback fake NVRAM */
+extern int fake_nvram_info(uint32_t *total_size);
+extern int fake_nvram_start_read(void *dst, uint32_t src, uint32_t len);
+extern int fake_nvram_write(uint32_t offset, void *src, uint32_t size);
+
 #endif /* __SKIBOOT_H */
-- 
2.9.3