chromeos: provide option to dynamically allocate ram oops buffer

Fixing the location of the ram oops buffer can lead to certain
kernel and boot loaders being confused when there is a ram
reservation low in the address space. Alternatively provide
a mechanism to allocate the ram oops buffer in cbmem. As cbmem
is usually high in the address space it avoids low reservation
confusion.

The patch uncondtionally provides a GOOG9999 ACPI device with
a single memory resource describing the memory region used for
the ramoops region.

BUG=None
BRANCH=baytrail,haswell
TEST=Built and booted with and w/o dynamic ram oops. With
     the corresponding kernel change things behave correctly.

Change-Id: Ide2bb4434768c9f9b90e125adae4324cb1d2d073
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/5257
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

1 files changed, 99 insertions, 0 deletions

diff --git a/src/vendorcode/google/chromeos/ramoops.c b/src/vendorcode/google/chromeos/ramoops.c
new file mode 100644
index 0000000000..500bc907bc
--- /dev/null
+++ b/src/vendorcode/google/chromeos/ramoops.c
@@ -0,0 +1,99 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2014 Google Inc
+ *
+ * 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; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+
+#include <stddef.h>
+#include <stdint.h>
+#include <bootstate.h>
+#include <console/console.h>
+#include <cbmem.h>
+#include <device/device.h>
+#include "chromeos.h"
+
+static void set_ramoops(chromeos_acpi_t *chromeos, void *ram_oops, size_t size)
+{
+	if (chromeos == NULL) {
+		printk(BIOS_DEBUG, "chromeos gnvs is NULL. ramoops not set.\n");
+		return;
+	}
+
+	printk(BIOS_DEBUG, "Ramoops buffer: 0x%zx@0x%p.\n", size, ram_oops);
+	chromeos->ramoops_base = (uintptr_t)ram_oops;
+	chromeos->ramoops_len = size;
+}
+
+static void reserve_ram_oops_dynamic(chromeos_acpi_t *chromeos)
+{
+	const size_t size = CONFIG_CHROMEOS_RAMOOPS_RAM_SIZE;
+	void *ram_oops;
+
+	if (!IS_ENABLED(CONFIG_CHROMEOS_RAMOOPS_DYNAMIC))
+		return;
+
+	ram_oops = cbmem_add(CBMEM_ID_RAM_OOPS, size);
+
+	set_ramoops(chromeos, ram_oops, size);
+}
+
+#if CONFIG_CHROMEOS_RAMOOPS_DYNAMIC
+static inline void set_global_chromeos_pointer(chromeos_acpi_t *chromeos) {}
+#else /* !CONFIG_CHROMEOS_RAMOOPS_DYNAMIC */
+
+static const unsigned long ramoops_base = CONFIG_CHROMEOS_RAMOOPS_RAM_START;
+static const unsigned long ramoops_size = CONFIG_CHROMEOS_RAMOOPS_RAM_SIZE;
+
+/*
+ * Save pointer to chromeos structure in memory. This is needed because the
+ * memory reservation is not done when chromeos_init() is called. However,
+ * the pointer to the chromeos_acpi_t structure is needed to update the
+ * fields with the rserved base and size.
+ */
+static chromeos_acpi_t *g_chromeos;
+
+static void set_global_chromeos_pointer(chromeos_acpi_t *chromeos)
+{
+	g_chromeos = chromeos;
+}
+
+static void update_gnvs(void *arg)
+{
+	chromeos_acpi_t **chromeos = arg;
+
+	set_ramoops(*chromeos, (void *)ramoops_base, ramoops_size);
+}
+
+static BOOT_STATE_CALLBACK(bscb_ramoops, update_gnvs, &g_chromeos);
+
+void chromeos_reserve_ram_oops(struct device *dev, int idx)
+{
+	const unsigned long base = ramoops_base >> 10;
+	const unsigned long size = ramoops_size >> 10;
+
+	reserved_ram_resource(dev, idx, base, size);
+
+	boot_state_sched_on_exit(&bscb_ramoops, BS_WRITE_TABLES);
+}
+#endif /* CONFIG_CHROMEOS_RAMOOPS_DYNAMIC */
+
+void chromeos_ram_oops_init(chromeos_acpi_t *chromeos)
+{
+	set_global_chromeos_pointer(chromeos);
+	reserve_ram_oops_dynamic(chromeos);
+}
+