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-rw-r--r--drivers/clk/clk-highbank.c329
1 files changed, 329 insertions, 0 deletions
diff --git a/drivers/clk/clk-highbank.c b/drivers/clk/clk-highbank.c
new file mode 100644
index 000000000..2a0cea294
--- /dev/null
+++ b/drivers/clk/clk-highbank.c
@@ -0,0 +1,329 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2011-2012 Calxeda, Inc.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+#define HB_PLL_LOCK_500 0x20000000
+#define HB_PLL_LOCK 0x10000000
+#define HB_PLL_DIVF_SHIFT 20
+#define HB_PLL_DIVF_MASK 0x0ff00000
+#define HB_PLL_DIVQ_SHIFT 16
+#define HB_PLL_DIVQ_MASK 0x00070000
+#define HB_PLL_DIVR_SHIFT 8
+#define HB_PLL_DIVR_MASK 0x00001f00
+#define HB_PLL_RANGE_SHIFT 4
+#define HB_PLL_RANGE_MASK 0x00000070
+#define HB_PLL_BYPASS 0x00000008
+#define HB_PLL_RESET 0x00000004
+#define HB_PLL_EXT_BYPASS 0x00000002
+#define HB_PLL_EXT_ENA 0x00000001
+
+#define HB_PLL_VCO_MIN_FREQ 2133000000
+#define HB_PLL_MAX_FREQ HB_PLL_VCO_MIN_FREQ
+#define HB_PLL_MIN_FREQ (HB_PLL_VCO_MIN_FREQ / 64)
+
+#define HB_A9_BCLK_DIV_MASK 0x00000006
+#define HB_A9_BCLK_DIV_SHIFT 1
+#define HB_A9_PCLK_DIV 0x00000001
+
+struct hb_clk {
+ struct clk_hw hw;
+ void __iomem *reg;
+ char *parent_name;
+};
+#define to_hb_clk(p) container_of(p, struct hb_clk, hw)
+
+static int clk_pll_prepare(struct clk_hw *hwclk)
+ {
+ struct hb_clk *hbclk = to_hb_clk(hwclk);
+ u32 reg;
+
+ reg = readl(hbclk->reg);
+ reg &= ~HB_PLL_RESET;
+ writel(reg, hbclk->reg);
+
+ while ((readl(hbclk->reg) & HB_PLL_LOCK) == 0)
+ ;
+ while ((readl(hbclk->reg) & HB_PLL_LOCK_500) == 0)
+ ;
+
+ return 0;
+}
+
+static void clk_pll_unprepare(struct clk_hw *hwclk)
+{
+ struct hb_clk *hbclk = to_hb_clk(hwclk);
+ u32 reg;
+
+ reg = readl(hbclk->reg);
+ reg |= HB_PLL_RESET;
+ writel(reg, hbclk->reg);
+}
+
+static int clk_pll_enable(struct clk_hw *hwclk)
+{
+ struct hb_clk *hbclk = to_hb_clk(hwclk);
+ u32 reg;
+
+ reg = readl(hbclk->reg);
+ reg |= HB_PLL_EXT_ENA;
+ writel(reg, hbclk->reg);
+
+ return 0;
+}
+
+static void clk_pll_disable(struct clk_hw *hwclk)
+{
+ struct hb_clk *hbclk = to_hb_clk(hwclk);
+ u32 reg;
+
+ reg = readl(hbclk->reg);
+ reg &= ~HB_PLL_EXT_ENA;
+ writel(reg, hbclk->reg);
+}
+
+static unsigned long clk_pll_recalc_rate(struct clk_hw *hwclk,
+ unsigned long parent_rate)
+{
+ struct hb_clk *hbclk = to_hb_clk(hwclk);
+ unsigned long divf, divq, vco_freq, reg;
+
+ reg = readl(hbclk->reg);
+ if (reg & HB_PLL_EXT_BYPASS)
+ return parent_rate;
+
+ divf = (reg & HB_PLL_DIVF_MASK) >> HB_PLL_DIVF_SHIFT;
+ divq = (reg & HB_PLL_DIVQ_MASK) >> HB_PLL_DIVQ_SHIFT;
+ vco_freq = parent_rate * (divf + 1);
+
+ return vco_freq / (1 << divq);
+}
+
+static void clk_pll_calc(unsigned long rate, unsigned long ref_freq,
+ u32 *pdivq, u32 *pdivf)
+{
+ u32 divq, divf;
+ unsigned long vco_freq;
+
+ if (rate < HB_PLL_MIN_FREQ)
+ rate = HB_PLL_MIN_FREQ;
+ if (rate > HB_PLL_MAX_FREQ)
+ rate = HB_PLL_MAX_FREQ;
+
+ for (divq = 1; divq <= 6; divq++) {
+ if ((rate * (1 << divq)) >= HB_PLL_VCO_MIN_FREQ)
+ break;
+ }
+
+ vco_freq = rate * (1 << divq);
+ divf = (vco_freq + (ref_freq / 2)) / ref_freq;
+ divf--;
+
+ *pdivq = divq;
+ *pdivf = divf;
+}
+
+static long clk_pll_round_rate(struct clk_hw *hwclk, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ u32 divq, divf;
+ unsigned long ref_freq = *parent_rate;
+
+ clk_pll_calc(rate, ref_freq, &divq, &divf);
+
+ return (ref_freq * (divf + 1)) / (1 << divq);
+}
+
+static int clk_pll_set_rate(struct clk_hw *hwclk, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct hb_clk *hbclk = to_hb_clk(hwclk);
+ u32 divq, divf;
+ u32 reg;
+
+ clk_pll_calc(rate, parent_rate, &divq, &divf);
+
+ reg = readl(hbclk->reg);
+ if (divf != ((reg & HB_PLL_DIVF_MASK) >> HB_PLL_DIVF_SHIFT)) {
+ /* Need to re-lock PLL, so put it into bypass mode */
+ reg |= HB_PLL_EXT_BYPASS;
+ writel(reg | HB_PLL_EXT_BYPASS, hbclk->reg);
+
+ writel(reg | HB_PLL_RESET, hbclk->reg);
+ reg &= ~(HB_PLL_DIVF_MASK | HB_PLL_DIVQ_MASK);
+ reg |= (divf << HB_PLL_DIVF_SHIFT) | (divq << HB_PLL_DIVQ_SHIFT);
+ writel(reg | HB_PLL_RESET, hbclk->reg);
+ writel(reg, hbclk->reg);
+
+ while ((readl(hbclk->reg) & HB_PLL_LOCK) == 0)
+ ;
+ while ((readl(hbclk->reg) & HB_PLL_LOCK_500) == 0)
+ ;
+ reg |= HB_PLL_EXT_ENA;
+ reg &= ~HB_PLL_EXT_BYPASS;
+ } else {
+ writel(reg | HB_PLL_EXT_BYPASS, hbclk->reg);
+ reg &= ~HB_PLL_DIVQ_MASK;
+ reg |= divq << HB_PLL_DIVQ_SHIFT;
+ writel(reg | HB_PLL_EXT_BYPASS, hbclk->reg);
+ }
+ writel(reg, hbclk->reg);
+
+ return 0;
+}
+
+static const struct clk_ops clk_pll_ops = {
+ .prepare = clk_pll_prepare,
+ .unprepare = clk_pll_unprepare,
+ .enable = clk_pll_enable,
+ .disable = clk_pll_disable,
+ .recalc_rate = clk_pll_recalc_rate,
+ .round_rate = clk_pll_round_rate,
+ .set_rate = clk_pll_set_rate,
+};
+
+static unsigned long clk_cpu_periphclk_recalc_rate(struct clk_hw *hwclk,
+ unsigned long parent_rate)
+{
+ struct hb_clk *hbclk = to_hb_clk(hwclk);
+ u32 div = (readl(hbclk->reg) & HB_A9_PCLK_DIV) ? 8 : 4;
+ return parent_rate / div;
+}
+
+static const struct clk_ops a9periphclk_ops = {
+ .recalc_rate = clk_cpu_periphclk_recalc_rate,
+};
+
+static unsigned long clk_cpu_a9bclk_recalc_rate(struct clk_hw *hwclk,
+ unsigned long parent_rate)
+{
+ struct hb_clk *hbclk = to_hb_clk(hwclk);
+ u32 div = (readl(hbclk->reg) & HB_A9_BCLK_DIV_MASK) >> HB_A9_BCLK_DIV_SHIFT;
+
+ return parent_rate / (div + 2);
+}
+
+static const struct clk_ops a9bclk_ops = {
+ .recalc_rate = clk_cpu_a9bclk_recalc_rate,
+};
+
+static unsigned long clk_periclk_recalc_rate(struct clk_hw *hwclk,
+ unsigned long parent_rate)
+{
+ struct hb_clk *hbclk = to_hb_clk(hwclk);
+ u32 div;
+
+ div = readl(hbclk->reg) & 0x1f;
+ div++;
+ div *= 2;
+
+ return parent_rate / div;
+}
+
+static long clk_periclk_round_rate(struct clk_hw *hwclk, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ u32 div;
+
+ div = *parent_rate / rate;
+ div++;
+ div &= ~0x1;
+
+ return *parent_rate / div;
+}
+
+static int clk_periclk_set_rate(struct clk_hw *hwclk, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct hb_clk *hbclk = to_hb_clk(hwclk);
+ u32 div;
+
+ div = parent_rate / rate;
+ if (div & 0x1)
+ return -EINVAL;
+
+ writel(div >> 1, hbclk->reg);
+ return 0;
+}
+
+static const struct clk_ops periclk_ops = {
+ .recalc_rate = clk_periclk_recalc_rate,
+ .round_rate = clk_periclk_round_rate,
+ .set_rate = clk_periclk_set_rate,
+};
+
+static void __init hb_clk_init(struct device_node *node, const struct clk_ops *ops, unsigned long clkflags)
+{
+ u32 reg;
+ struct hb_clk *hb_clk;
+ const char *clk_name = node->name;
+ const char *parent_name;
+ struct clk_init_data init;
+ struct device_node *srnp;
+ int rc;
+
+ rc = of_property_read_u32(node, "reg", &reg);
+ if (WARN_ON(rc))
+ return;
+
+ hb_clk = kzalloc(sizeof(*hb_clk), GFP_KERNEL);
+ if (WARN_ON(!hb_clk))
+ return;
+
+ /* Map system registers */
+ srnp = of_find_compatible_node(NULL, NULL, "calxeda,hb-sregs");
+ hb_clk->reg = of_iomap(srnp, 0);
+ of_node_put(srnp);
+ BUG_ON(!hb_clk->reg);
+ hb_clk->reg += reg;
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+
+ init.name = clk_name;
+ init.ops = ops;
+ init.flags = clkflags;
+ parent_name = of_clk_get_parent_name(node, 0);
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ hb_clk->hw.init = &init;
+
+ rc = clk_hw_register(NULL, &hb_clk->hw);
+ if (WARN_ON(rc)) {
+ kfree(hb_clk);
+ return;
+ }
+ of_clk_add_hw_provider(node, of_clk_hw_simple_get, &hb_clk->hw);
+}
+
+static void __init hb_pll_init(struct device_node *node)
+{
+ hb_clk_init(node, &clk_pll_ops, 0);
+}
+CLK_OF_DECLARE(hb_pll, "calxeda,hb-pll-clock", hb_pll_init);
+
+static void __init hb_a9periph_init(struct device_node *node)
+{
+ hb_clk_init(node, &a9periphclk_ops, 0);
+}
+CLK_OF_DECLARE(hb_a9periph, "calxeda,hb-a9periph-clock", hb_a9periph_init);
+
+static void __init hb_a9bus_init(struct device_node *node)
+{
+ hb_clk_init(node, &a9bclk_ops, CLK_IS_CRITICAL);
+}
+CLK_OF_DECLARE(hb_a9bus, "calxeda,hb-a9bus-clock", hb_a9bus_init);
+
+static void __init hb_emmc_init(struct device_node *node)
+{
+ hb_clk_init(node, &periclk_ops, 0);
+}
+CLK_OF_DECLARE(hb_emmc, "calxeda,hb-emmc-clock", hb_emmc_init);