1 files changed, 101 insertions, 0 deletions
diff --git a/grub-core/kern/arm/coreboot/timer.c b/grub-core/kern/arm/coreboot/timer.c
new file mode 100644
index 0000000..d97b844
--- /dev/null
+++ b/grub-core/kern/arm/coreboot/timer.c
@@ -0,0 +1,101 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2016  Free Software Foundation, Inc.
+ *
+ *  GRUB 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 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB 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 GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/mm.h>
+#include <grub/machine/kernel.h>
+#include <grub/types.h>
+#include <grub/err.h>
+#include <grub/time.h>
+#include <grub/fdtbus.h>
+#include <grub/misc.h>
+
+grub_uint64_t
+grub_armv7_get_timer_value(void);
+
+grub_uint32_t
+grub_armv7_get_timer_frequency(void);
+
+grub_uint32_t
+grub_arm_pfr1(void);
+
+static int have_timer = 0;
+static volatile grub_uint32_t *sp804_regs;
+
+static grub_uint64_t
+sp804_get_time_ms (void)
+{
+  static grub_uint32_t high, last_low;
+  grub_uint32_t low = ~sp804_regs[1];
+  if (last_low > low)
+    high++;
+  last_low = low;
+  return grub_divmod64 ((((grub_uint64_t) high) << 32) | low,
+			1000, 0);
+}
+
+static grub_err_t
+sp804_attach(const struct grub_fdtbus_dev *dev)
+{
+  if (have_timer)
+    return GRUB_ERR_NONE;
+  sp804_regs = grub_fdtbus_map_reg (dev, 0, 0);
+  if (!grub_fdtbus_is_mapping_valid (sp804_regs))
+    return grub_error (GRUB_ERR_IO, "could not map sp804: %p", sp804_regs);
+  grub_install_get_time_ms (sp804_get_time_ms);
+  have_timer = 1;
+  return GRUB_ERR_NONE;
+}
+
+struct grub_fdtbus_driver sp804 =
+{
+  .compatible = "arm,sp804",
+  .attach = sp804_attach
+};
+
+static grub_uint32_t timer_frequency_in_khz;
+
+static grub_uint64_t
+generic_get_time_ms (void)
+{
+  return grub_divmod64 (grub_armv7_get_timer_value(), timer_frequency_in_khz, 0);
+}
+
+static int
+try_generic_timer (void)
+{
+  if (((grub_arm_pfr1 () >> 16) & 0xf) != 1)
+    return 0;
+  grub_printf ("freq = %x\n", grub_armv7_get_timer_frequency());
+  timer_frequency_in_khz = 0x016e3600 / 1000; //grub_armv7_get_timer_frequency() / 1000;
+  if (timer_frequency_in_khz == 0)
+    return 0;
+  grub_install_get_time_ms (generic_get_time_ms);
+  have_timer = 1;
+  return 1;
+}
+
+void
+grub_machine_timer_init (void)
+{
+  grub_fdtbus_register (&sp804);
+
+  if (!have_timer)
+    try_generic_timer ();
+  if (!have_timer)
+    grub_fatal ("No timer found");
+}