Change in coreboot[master]: uart/sifive: provide a monotonic timer using CLINT timer register

[Philipp Hug (Code Review)]

Philipp Hug has uploaded this change for review. ( https://review.coreboot.org/27434

Change subject: uart/sifive: provide a monotonic timer using CLINT timer register
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uart/sifive: provide a monotonic timer using CLINT timer register

Makes it possible to use the generic udelay.

Change-Id: I5139601226e6f89da69e302a10f2fb56b4b24f38
Signed-off-by: Philipp Hug 
---
M src/arch/riscv/misc.c
M src/soc/sifive/fu540/Kconfig
M src/soc/sifive/fu540/Makefile.inc
A src/soc/sifive/fu540/timer.c
4 files changed, 29 insertions(+), 4 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/34/27434/1

diff --git a/src/arch/riscv/misc.c b/src/arch/riscv/misc.c
index 65b8ecf..1909dbc 100644
--- a/src/arch/riscv/misc.c
+++ b/src/arch/riscv/misc.c
@@ -16,7 +16,3 @@
 void init_timer(void)
 {
 }
-
-void udelay(unsigned int n)
-{
-}
diff --git a/src/soc/sifive/fu540/Kconfig b/src/soc/sifive/fu540/Kconfig
index d247c28..4db34f7 100644
--- a/src/soc/sifive/fu540/Kconfig
+++ b/src/soc/sifive/fu540/Kconfig
@@ -20,6 +20,8 @@
    select ARCH_RAMSTAGE_RISCV
    select BOOTBLOCK_CONSOLE
    select DRIVERS_UART_SIFIVE
+	select HAVE_MONOTONIC_TIMER
+	select GENERIC_UDELAY

if SOC_SIFIVE_FU540

diff --git a/src/soc/sifive/fu540/Makefile.inc b/src/soc/sifive/fu540/Makefile.inc
index 8a2f3a6..4ac080b 100644
--- a/src/soc/sifive/fu540/Makefile.inc
+++ b/src/soc/sifive/fu540/Makefile.inc
@@ -19,10 +19,12 @@

romstage-y += uart.c
 romstage-y += media.c
+romstage-y += timer.c

ramstage-y += uart.c
 ramstage-y += media.c
 ramstage-y += cbmem.c
+ramstage-y += timer.c

CPPFLAGS_common += -Isrc/soc/sifive/fu540/include

diff --git a/src/soc/sifive/fu540/timer.c b/src/soc/sifive/fu540/timer.c
new file mode 100644
index 0000000..57afc88
--- /dev/null
+++ b/src/soc/sifive/fu540/timer.c
@@ -0,0 +1,25 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2018 Philipp Hug 
+ *
+ * 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.
+ */
+
+#include <arch/io.h>
+#include <arch/encoding.h>
+#include <timer.h>
+
+#define CLINT_MTIME CLINT_BASE + 0xbff8
+
+void timer_monotonic_get(struct mono_time *mt)
+{
+	mono_time_set_usecs(mt, read32((void *)(CLINT_MTIME)));
+}