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authorAndrew Bresticker <abrestic@chromium.org>2015-02-24 19:56:03 -0800
committerRalf Baechle <ralf@linux-mips.org>2015-03-31 11:59:04 +0200
commit43049b0c83f177083a56d69e64e47c82bcc04185 (patch)
treeb5a77282449ac612c44b42aea1fbdb76ad1c31e8 /drivers/clk/pistachio
parent8e4b7721f61e70396ad8ec2d866c91300f2afbd1 (diff)
downloadlinux-43049b0c83f177083a56d69e64e47c82bcc04185.tar.bz2
CLK: Pistachio: Add PLL driver
Add a driver for the integer (GF40LP_LAINT) and fractional (GF40LP_FRAC) PLLs present on Pistachio. Signed-off-by: Andrew Bresticker <abrestic@chromium.org> Cc: Mike Turquette <mturquette@linaro.org> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: devicetree@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Cc: Ezequiel Garcia <ezequiel.garcia@imgtec.com> Cc: James Hartley <james.hartley@imgtec.com> Cc: James Hogan <james.hogan@imgtec.com> Acked-by: Stephen Boyd <sboyd@codeaurora.org> Patchwork: https://patchwork.linux-mips.org/patch/9316/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'drivers/clk/pistachio')
-rw-r--r--drivers/clk/pistachio/Makefile1
-rw-r--r--drivers/clk/pistachio/clk-pll.c401
-rw-r--r--drivers/clk/pistachio/clk.h50
3 files changed, 452 insertions, 0 deletions
diff --git a/drivers/clk/pistachio/Makefile b/drivers/clk/pistachio/Makefile
index fc216adb744e..a93490dbe3e1 100644
--- a/drivers/clk/pistachio/Makefile
+++ b/drivers/clk/pistachio/Makefile
@@ -1 +1,2 @@
obj-y += clk.o
+obj-y += clk-pll.o
diff --git a/drivers/clk/pistachio/clk-pll.c b/drivers/clk/pistachio/clk-pll.c
new file mode 100644
index 000000000000..de537560bf70
--- /dev/null
+++ b/drivers/clk/pistachio/clk-pll.c
@@ -0,0 +1,401 @@
+/*
+ * Copyright (C) 2014 Google, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+
+#include "clk.h"
+
+#define PLL_STATUS 0x0
+#define PLL_STATUS_LOCK BIT(0)
+
+#define PLL_CTRL1 0x4
+#define PLL_CTRL1_REFDIV_SHIFT 0
+#define PLL_CTRL1_REFDIV_MASK 0x3f
+#define PLL_CTRL1_FBDIV_SHIFT 6
+#define PLL_CTRL1_FBDIV_MASK 0xfff
+#define PLL_INT_CTRL1_POSTDIV1_SHIFT 18
+#define PLL_INT_CTRL1_POSTDIV1_MASK 0x7
+#define PLL_INT_CTRL1_POSTDIV2_SHIFT 21
+#define PLL_INT_CTRL1_POSTDIV2_MASK 0x7
+#define PLL_INT_CTRL1_PD BIT(24)
+#define PLL_INT_CTRL1_DSMPD BIT(25)
+#define PLL_INT_CTRL1_FOUTPOSTDIVPD BIT(26)
+#define PLL_INT_CTRL1_FOUTVCOPD BIT(27)
+
+#define PLL_CTRL2 0x8
+#define PLL_FRAC_CTRL2_FRAC_SHIFT 0
+#define PLL_FRAC_CTRL2_FRAC_MASK 0xffffff
+#define PLL_FRAC_CTRL2_POSTDIV1_SHIFT 24
+#define PLL_FRAC_CTRL2_POSTDIV1_MASK 0x7
+#define PLL_FRAC_CTRL2_POSTDIV2_SHIFT 27
+#define PLL_FRAC_CTRL2_POSTDIV2_MASK 0x7
+#define PLL_INT_CTRL2_BYPASS BIT(28)
+
+#define PLL_CTRL3 0xc
+#define PLL_FRAC_CTRL3_PD BIT(0)
+#define PLL_FRAC_CTRL3_DACPD BIT(1)
+#define PLL_FRAC_CTRL3_DSMPD BIT(2)
+#define PLL_FRAC_CTRL3_FOUTPOSTDIVPD BIT(3)
+#define PLL_FRAC_CTRL3_FOUT4PHASEPD BIT(4)
+#define PLL_FRAC_CTRL3_FOUTVCOPD BIT(5)
+
+#define PLL_CTRL4 0x10
+#define PLL_FRAC_CTRL4_BYPASS BIT(28)
+
+struct pistachio_clk_pll {
+ struct clk_hw hw;
+ void __iomem *base;
+ struct pistachio_pll_rate_table *rates;
+ unsigned int nr_rates;
+};
+
+static inline u32 pll_readl(struct pistachio_clk_pll *pll, u32 reg)
+{
+ return readl(pll->base + reg);
+}
+
+static inline void pll_writel(struct pistachio_clk_pll *pll, u32 val, u32 reg)
+{
+ writel(val, pll->base + reg);
+}
+
+static inline u32 do_div_round_closest(u64 dividend, u32 divisor)
+{
+ dividend += divisor / 2;
+ do_div(dividend, divisor);
+
+ return dividend;
+}
+
+static inline struct pistachio_clk_pll *to_pistachio_pll(struct clk_hw *hw)
+{
+ return container_of(hw, struct pistachio_clk_pll, hw);
+}
+
+static struct pistachio_pll_rate_table *
+pll_get_params(struct pistachio_clk_pll *pll, unsigned long fref,
+ unsigned long fout)
+{
+ unsigned int i;
+
+ for (i = 0; i < pll->nr_rates; i++) {
+ if (pll->rates[i].fref == fref && pll->rates[i].fout == fout)
+ return &pll->rates[i];
+ }
+
+ return NULL;
+}
+
+static long pll_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ unsigned int i;
+
+ for (i = 0; i < pll->nr_rates; i++) {
+ if (i > 0 && pll->rates[i].fref == *parent_rate &&
+ pll->rates[i].fout <= rate)
+ return pll->rates[i - 1].fout;
+ }
+
+ return pll->rates[0].fout;
+}
+
+static int pll_gf40lp_frac_enable(struct clk_hw *hw)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u32 val;
+
+ val = pll_readl(pll, PLL_CTRL3);
+ val &= ~(PLL_FRAC_CTRL3_PD | PLL_FRAC_CTRL3_DACPD |
+ PLL_FRAC_CTRL3_DSMPD | PLL_FRAC_CTRL3_FOUTPOSTDIVPD |
+ PLL_FRAC_CTRL3_FOUT4PHASEPD | PLL_FRAC_CTRL3_FOUTVCOPD);
+ pll_writel(pll, val, PLL_CTRL3);
+
+ val = pll_readl(pll, PLL_CTRL4);
+ val &= ~PLL_FRAC_CTRL4_BYPASS;
+ pll_writel(pll, val, PLL_CTRL4);
+
+ return 0;
+}
+
+static void pll_gf40lp_frac_disable(struct clk_hw *hw)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u32 val;
+
+ val = pll_readl(pll, PLL_CTRL3);
+ val |= PLL_FRAC_CTRL3_PD;
+ pll_writel(pll, val, PLL_CTRL3);
+}
+
+static int pll_gf40lp_frac_is_enabled(struct clk_hw *hw)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+
+ return !(pll_readl(pll, PLL_CTRL3) & PLL_FRAC_CTRL3_PD);
+}
+
+static int pll_gf40lp_frac_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ struct pistachio_pll_rate_table *params;
+ bool was_enabled;
+ u32 val;
+
+ params = pll_get_params(pll, parent_rate, rate);
+ if (!params)
+ return -EINVAL;
+
+ was_enabled = pll_gf40lp_frac_is_enabled(hw);
+ if (!was_enabled)
+ pll_gf40lp_frac_enable(hw);
+
+ val = pll_readl(pll, PLL_CTRL1);
+ val &= ~((PLL_CTRL1_REFDIV_MASK << PLL_CTRL1_REFDIV_SHIFT) |
+ (PLL_CTRL1_FBDIV_MASK << PLL_CTRL1_FBDIV_SHIFT));
+ val |= (params->refdiv << PLL_CTRL1_REFDIV_SHIFT) |
+ (params->fbdiv << PLL_CTRL1_FBDIV_SHIFT);
+ pll_writel(pll, val, PLL_CTRL1);
+
+ val = pll_readl(pll, PLL_CTRL2);
+ val &= ~((PLL_FRAC_CTRL2_FRAC_MASK << PLL_FRAC_CTRL2_FRAC_SHIFT) |
+ (PLL_FRAC_CTRL2_POSTDIV1_MASK <<
+ PLL_FRAC_CTRL2_POSTDIV1_SHIFT) |
+ (PLL_FRAC_CTRL2_POSTDIV2_MASK <<
+ PLL_FRAC_CTRL2_POSTDIV2_SHIFT));
+ val |= (params->frac << PLL_FRAC_CTRL2_FRAC_SHIFT) |
+ (params->postdiv1 << PLL_FRAC_CTRL2_POSTDIV1_SHIFT) |
+ (params->postdiv2 << PLL_FRAC_CTRL2_POSTDIV2_SHIFT);
+ pll_writel(pll, val, PLL_CTRL2);
+
+ while (!(pll_readl(pll, PLL_STATUS) & PLL_STATUS_LOCK))
+ cpu_relax();
+
+ if (!was_enabled)
+ pll_gf40lp_frac_disable(hw);
+
+ return 0;
+}
+
+static unsigned long pll_gf40lp_frac_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u32 val, prediv, fbdiv, frac, postdiv1, postdiv2;
+ u64 rate = parent_rate;
+
+ val = pll_readl(pll, PLL_CTRL1);
+ prediv = (val >> PLL_CTRL1_REFDIV_SHIFT) & PLL_CTRL1_REFDIV_MASK;
+ fbdiv = (val >> PLL_CTRL1_FBDIV_SHIFT) & PLL_CTRL1_FBDIV_MASK;
+
+ val = pll_readl(pll, PLL_CTRL2);
+ postdiv1 = (val >> PLL_FRAC_CTRL2_POSTDIV1_SHIFT) &
+ PLL_FRAC_CTRL2_POSTDIV1_MASK;
+ postdiv2 = (val >> PLL_FRAC_CTRL2_POSTDIV2_SHIFT) &
+ PLL_FRAC_CTRL2_POSTDIV2_MASK;
+ frac = (val >> PLL_FRAC_CTRL2_FRAC_SHIFT) & PLL_FRAC_CTRL2_FRAC_MASK;
+
+ rate *= (fbdiv << 24) + frac;
+ rate = do_div_round_closest(rate, (prediv * postdiv1 * postdiv2) << 24);
+
+ return rate;
+}
+
+static struct clk_ops pll_gf40lp_frac_ops = {
+ .enable = pll_gf40lp_frac_enable,
+ .disable = pll_gf40lp_frac_disable,
+ .is_enabled = pll_gf40lp_frac_is_enabled,
+ .recalc_rate = pll_gf40lp_frac_recalc_rate,
+ .round_rate = pll_round_rate,
+ .set_rate = pll_gf40lp_frac_set_rate,
+};
+
+static struct clk_ops pll_gf40lp_frac_fixed_ops = {
+ .enable = pll_gf40lp_frac_enable,
+ .disable = pll_gf40lp_frac_disable,
+ .is_enabled = pll_gf40lp_frac_is_enabled,
+ .recalc_rate = pll_gf40lp_frac_recalc_rate,
+};
+
+static int pll_gf40lp_laint_enable(struct clk_hw *hw)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u32 val;
+
+ val = pll_readl(pll, PLL_CTRL1);
+ val &= ~(PLL_INT_CTRL1_PD | PLL_INT_CTRL1_DSMPD |
+ PLL_INT_CTRL1_FOUTPOSTDIVPD | PLL_INT_CTRL1_FOUTVCOPD);
+ pll_writel(pll, val, PLL_CTRL1);
+
+ val = pll_readl(pll, PLL_CTRL2);
+ val &= ~PLL_INT_CTRL2_BYPASS;
+ pll_writel(pll, val, PLL_CTRL2);
+
+ return 0;
+}
+
+static void pll_gf40lp_laint_disable(struct clk_hw *hw)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u32 val;
+
+ val = pll_readl(pll, PLL_CTRL1);
+ val |= PLL_INT_CTRL1_PD;
+ pll_writel(pll, val, PLL_CTRL1);
+}
+
+static int pll_gf40lp_laint_is_enabled(struct clk_hw *hw)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+
+ return !(pll_readl(pll, PLL_CTRL1) & PLL_INT_CTRL1_PD);
+}
+
+static int pll_gf40lp_laint_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ struct pistachio_pll_rate_table *params;
+ bool was_enabled;
+ u32 val;
+
+ params = pll_get_params(pll, parent_rate, rate);
+ if (!params)
+ return -EINVAL;
+
+ was_enabled = pll_gf40lp_laint_is_enabled(hw);
+ if (!was_enabled)
+ pll_gf40lp_laint_enable(hw);
+
+ val = pll_readl(pll, PLL_CTRL1);
+ val &= ~((PLL_CTRL1_REFDIV_MASK << PLL_CTRL1_REFDIV_SHIFT) |
+ (PLL_CTRL1_FBDIV_MASK << PLL_CTRL1_FBDIV_SHIFT) |
+ (PLL_INT_CTRL1_POSTDIV1_MASK << PLL_INT_CTRL1_POSTDIV1_SHIFT) |
+ (PLL_INT_CTRL1_POSTDIV2_MASK << PLL_INT_CTRL1_POSTDIV2_SHIFT));
+ val |= (params->refdiv << PLL_CTRL1_REFDIV_SHIFT) |
+ (params->fbdiv << PLL_CTRL1_FBDIV_SHIFT) |
+ (params->postdiv1 << PLL_INT_CTRL1_POSTDIV1_SHIFT) |
+ (params->postdiv2 << PLL_INT_CTRL1_POSTDIV2_SHIFT);
+ pll_writel(pll, val, PLL_CTRL1);
+
+ while (!(pll_readl(pll, PLL_STATUS) & PLL_STATUS_LOCK))
+ cpu_relax();
+
+ if (!was_enabled)
+ pll_gf40lp_laint_disable(hw);
+
+ return 0;
+}
+
+static unsigned long pll_gf40lp_laint_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct pistachio_clk_pll *pll = to_pistachio_pll(hw);
+ u32 val, prediv, fbdiv, postdiv1, postdiv2;
+ u64 rate = parent_rate;
+
+ val = pll_readl(pll, PLL_CTRL1);
+ prediv = (val >> PLL_CTRL1_REFDIV_SHIFT) & PLL_CTRL1_REFDIV_MASK;
+ fbdiv = (val >> PLL_CTRL1_FBDIV_SHIFT) & PLL_CTRL1_FBDIV_MASK;
+ postdiv1 = (val >> PLL_INT_CTRL1_POSTDIV1_SHIFT) &
+ PLL_INT_CTRL1_POSTDIV1_MASK;
+ postdiv2 = (val >> PLL_INT_CTRL1_POSTDIV2_SHIFT) &
+ PLL_INT_CTRL1_POSTDIV2_MASK;
+
+ rate *= fbdiv;
+ rate = do_div_round_closest(rate, prediv * postdiv1 * postdiv2);
+
+ return rate;
+}
+
+static struct clk_ops pll_gf40lp_laint_ops = {
+ .enable = pll_gf40lp_laint_enable,
+ .disable = pll_gf40lp_laint_disable,
+ .is_enabled = pll_gf40lp_laint_is_enabled,
+ .recalc_rate = pll_gf40lp_laint_recalc_rate,
+ .round_rate = pll_round_rate,
+ .set_rate = pll_gf40lp_laint_set_rate,
+};
+
+static struct clk_ops pll_gf40lp_laint_fixed_ops = {
+ .enable = pll_gf40lp_laint_enable,
+ .disable = pll_gf40lp_laint_disable,
+ .is_enabled = pll_gf40lp_laint_is_enabled,
+ .recalc_rate = pll_gf40lp_laint_recalc_rate,
+};
+
+static struct clk *pll_register(const char *name, const char *parent_name,
+ unsigned long flags, void __iomem *base,
+ enum pistachio_pll_type type,
+ struct pistachio_pll_rate_table *rates,
+ unsigned int nr_rates)
+{
+ struct pistachio_clk_pll *pll;
+ struct clk_init_data init;
+ struct clk *clk;
+
+ pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+ if (!pll)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.flags = flags | CLK_GET_RATE_NOCACHE;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+
+ switch (type) {
+ case PLL_GF40LP_FRAC:
+ if (rates)
+ init.ops = &pll_gf40lp_frac_ops;
+ else
+ init.ops = &pll_gf40lp_frac_fixed_ops;
+ break;
+ case PLL_GF40LP_LAINT:
+ if (rates)
+ init.ops = &pll_gf40lp_laint_ops;
+ else
+ init.ops = &pll_gf40lp_laint_fixed_ops;
+ break;
+ default:
+ pr_err("Unrecognized PLL type %u\n", type);
+ kfree(pll);
+ return ERR_PTR(-EINVAL);
+ }
+
+ pll->hw.init = &init;
+ pll->base = base;
+ pll->rates = rates;
+ pll->nr_rates = nr_rates;
+
+ clk = clk_register(NULL, &pll->hw);
+ if (IS_ERR(clk))
+ kfree(pll);
+
+ return clk;
+}
+
+void pistachio_clk_register_pll(struct pistachio_clk_provider *p,
+ struct pistachio_pll *pll,
+ unsigned int num)
+{
+ struct clk *clk;
+ unsigned int i;
+
+ for (i = 0; i < num; i++) {
+ clk = pll_register(pll[i].name, pll[i].parent,
+ 0, p->base + pll[i].reg_base,
+ pll[i].type, pll[i].rates,
+ pll[i].nr_rates);
+ p->clk_data.clks[pll[i].id] = clk;
+ }
+}
diff --git a/drivers/clk/pistachio/clk.h b/drivers/clk/pistachio/clk.h
index e735107ddab0..52fabbc24624 100644
--- a/drivers/clk/pistachio/clk.h
+++ b/drivers/clk/pistachio/clk.h
@@ -94,6 +94,53 @@ struct pistachio_fixed_factor {
.parent = _pname, \
}
+struct pistachio_pll_rate_table {
+ unsigned long fref;
+ unsigned long fout;
+ unsigned int refdiv;
+ unsigned int fbdiv;
+ unsigned int postdiv1;
+ unsigned int postdiv2;
+ unsigned int frac;
+};
+
+enum pistachio_pll_type {
+ PLL_GF40LP_LAINT,
+ PLL_GF40LP_FRAC,
+};
+
+struct pistachio_pll {
+ unsigned int id;
+ unsigned long reg_base;
+ enum pistachio_pll_type type;
+ struct pistachio_pll_rate_table *rates;
+ unsigned int nr_rates;
+ const char *name;
+ const char *parent;
+};
+
+#define PLL(_id, _name, _pname, _type, _reg, _rates) \
+ { \
+ .id = _id, \
+ .reg_base = _reg, \
+ .type = _type, \
+ .rates = _rates, \
+ .nr_rates = ARRAY_SIZE(_rates), \
+ .name = _name, \
+ .parent = _pname, \
+ }
+
+#define PLL_FIXED(_id, _name, _pname, _type, _reg) \
+ { \
+ .id = _id, \
+ .reg_base = _reg, \
+ .type = _type, \
+ .rates = NULL, \
+ .nr_rates = 0, \
+ .name = _name, \
+ .parent = _pname, \
+ }
+
struct pistachio_clk_provider {
struct device_node *node;
void __iomem *base;
@@ -117,6 +164,9 @@ extern void
pistachio_clk_register_fixed_factor(struct pistachio_clk_provider *p,
struct pistachio_fixed_factor *ff,
unsigned int num);
+extern void pistachio_clk_register_pll(struct pistachio_clk_provider *p,
+ struct pistachio_pll *pll,
+ unsigned int num);
extern void pistachio_clk_force_enable(struct pistachio_clk_provider *p,
unsigned int *clk_ids, unsigned int num);