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path: root/drivers/timer/ast_timer.c
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Diffstat (limited to 'drivers/timer/ast_timer.c')
-rw-r--r--drivers/timer/ast_timer.c97
1 files changed, 97 insertions, 0 deletions
diff --git a/drivers/timer/ast_timer.c b/drivers/timer/ast_timer.c
new file mode 100644
index 0000000000..d7c5460cd3
--- /dev/null
+++ b/drivers/timer/ast_timer.c
@@ -0,0 +1,97 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <timer.h>
+#include <asm/io.h>
+#include <asm/arch/timer.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define AST_TICK_TIMER 1
+#define AST_TMC_RELOAD_VAL 0xffffffff
+
+struct ast_timer_priv {
+ struct ast_timer *regs;
+ struct ast_timer_counter *tmc;
+};
+
+static struct ast_timer_counter *ast_get_timer_counter(struct ast_timer *timer,
+ int n)
+{
+ if (n > 3)
+ return &timer->timers2[n - 4];
+ else
+ return &timer->timers1[n - 1];
+}
+
+static int ast_timer_probe(struct udevice *dev)
+{
+ struct ast_timer_priv *priv = dev_get_priv(dev);
+ struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+
+ writel(AST_TMC_RELOAD_VAL, &priv->tmc->reload_val);
+
+ /*
+ * Stop the timer. This will also load reload_val into
+ * the status register.
+ */
+ clrbits_le32(&priv->regs->ctrl1,
+ AST_TMC_EN << AST_TMC_CTRL1_SHIFT(AST_TICK_TIMER));
+ /* Start the timer from the fixed 1MHz clock. */
+ setbits_le32(&priv->regs->ctrl1,
+ (AST_TMC_EN | AST_TMC_1MHZ) <<
+ AST_TMC_CTRL1_SHIFT(AST_TICK_TIMER));
+
+ uc_priv->clock_rate = AST_TMC_RATE;
+
+ return 0;
+}
+
+static int ast_timer_get_count(struct udevice *dev, u64 *count)
+{
+ struct ast_timer_priv *priv = dev_get_priv(dev);
+
+ *count = AST_TMC_RELOAD_VAL - readl(&priv->tmc->status);
+
+ return 0;
+}
+
+static int ast_timer_ofdata_to_platdata(struct udevice *dev)
+{
+ struct ast_timer_priv *priv = dev_get_priv(dev);
+
+ priv->regs = dev_get_addr_ptr(dev);
+ if (IS_ERR(priv->regs))
+ return PTR_ERR(priv->regs);
+
+ priv->tmc = ast_get_timer_counter(priv->regs, AST_TICK_TIMER);
+
+ return 0;
+}
+
+static const struct timer_ops ast_timer_ops = {
+ .get_count = ast_timer_get_count,
+};
+
+static const struct udevice_id ast_timer_ids[] = {
+ { .compatible = "aspeed,ast2500-timer" },
+ { .compatible = "aspeed,ast2400-timer" },
+ { }
+};
+
+U_BOOT_DRIVER(ast_timer) = {
+ .name = "ast_timer",
+ .id = UCLASS_TIMER,
+ .of_match = ast_timer_ids,
+ .probe = ast_timer_probe,
+ .priv_auto_alloc_size = sizeof(struct ast_timer_priv),
+ .ofdata_to_platdata = ast_timer_ofdata_to_platdata,
+ .ops = &ast_timer_ops,
+ .flags = DM_FLAG_PRE_RELOC,
+};