timer: MediaTek: add timer driver for MediaTek SoCs

This patch adds clock source and clock event for the timer found
on the Mediatek SoCs.

Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Tested-by: Matthias Brugger <matthias.bgg@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

diff --git a/drivers/timer/Kconfig b/drivers/timer/Kconfig
index d0cfc35..b0e6f32 100644 (file)
--- a/drivers/timer/Kconfig
+++ b/drivers/timer/Kconfig
@@ -160,4 +160,11 @@ config X86_TSC_TIMER
        help
          Select this to enable Time-Stamp Counter (TSC) timer for x86.
 
        help
          Select this to enable Time-Stamp Counter (TSC) timer for x86.
 

+config MTK_TIMER
+       bool "MediaTek timer support"
+       depends on TIMER
+       help
+         Select this to enable support for the timer found on
+         MediaTek devices.
+

 endmenu
 endmenu

diff --git a/drivers/timer/Makefile b/drivers/timer/Makefile
index 7f19c49..c4fbab2 100644 (file)
--- a/drivers/timer/Makefile
+++ b/drivers/timer/Makefile
@@ -18,3 +18,4 @@ obj-$(CONFIG_SANDBOX_TIMER)   += sandbox_timer.o
 obj-$(CONFIG_STI_TIMER)                += sti-timer.o
 obj-$(CONFIG_STM32_TIMER)      += stm32_timer.o
 obj-$(CONFIG_X86_TSC_TIMER)    += tsc_timer.o
 obj-$(CONFIG_STI_TIMER)                += sti-timer.o
 obj-$(CONFIG_STM32_TIMER)      += stm32_timer.o
 obj-$(CONFIG_X86_TSC_TIMER)    += tsc_timer.o

+obj-$(CONFIG_MTK_TIMER)                += mtk_timer.o

diff --git a/drivers/timer/mtk_timer.c b/drivers/timer/mtk_timer.c
new file mode 100644 (file)
index 0000000..b5e76bd
--- /dev/null
+++ b/drivers/timer/mtk_timer.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MediaTek timer driver
+ *
+ * Copyright (C) 2018 MediaTek Inc.
+ * Author: Ryder Lee <ryder.lee@mediatek.com>
+ */
+
+#include <clk.h>
+#include <common.h>
+#include <dm.h>
+#include <timer.h>
+#include <asm/io.h>
+
+#define MTK_GPT4_CTRL  0x40
+#define MTK_GPT4_CLK   0x44
+#define MTK_GPT4_CNT   0x48
+
+#define GPT4_ENABLE    BIT(0)
+#define GPT4_CLEAR     BIT(1)
+#define GPT4_FREERUN   GENMASK(5, 4)
+#define GPT4_CLK_SYS   0x0
+#define GPT4_CLK_DIV1  0x0
+
+struct mtk_timer_priv {
+       void __iomem *base;
+};
+
+static int mtk_timer_get_count(struct udevice *dev, u64 *count)
+{
+       struct mtk_timer_priv *priv = dev_get_priv(dev);
+       u32 val = readl(priv->base + MTK_GPT4_CNT);
+
+       *count = timer_conv_64(val);
+
+       return 0;
+}
+
+static int mtk_timer_probe(struct udevice *dev)
+{
+       struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+       struct mtk_timer_priv *priv = dev_get_priv(dev);
+       struct clk clk, parent;
+       int ret;
+
+       priv->base = dev_read_addr_ptr(dev);
+       if (!priv->base)
+               return -ENOENT;
+
+       ret = clk_get_by_index(dev, 0, &clk);
+       if (ret)
+               return ret;
+
+       ret = clk_get_by_index(dev, 1, &parent);
+       if (!ret) {
+               ret = clk_set_parent(&clk, &parent);
+               if (ret)
+                       return ret;
+       }
+
+       uc_priv->clock_rate = clk_get_rate(&clk);
+       if (!uc_priv->clock_rate)
+               return -EINVAL;
+
+       return 0;
+}
+
+static const struct timer_ops mtk_timer_ops = {
+       .get_count = mtk_timer_get_count,
+};
+
+static const struct udevice_id mtk_timer_ids[] = {
+       { .compatible = "mediatek,timer" },
+       { }
+};
+
+U_BOOT_DRIVER(mtk_timer) = {
+       .name = "mtk_timer",
+       .id = UCLASS_TIMER,
+       .of_match = mtk_timer_ids,
+       .priv_auto_alloc_size = sizeof(struct mtk_timer_priv),
+       .probe = mtk_timer_probe,
+       .ops = &mtk_timer_ops,
+       .flags = DM_FLAG_PRE_RELOC,
+};