[PATCH V1 7/9] clk: sprd: add adjustable pll support
Chunyan Zhang
chunyan.zhang at spreadtrum.com
Sat Jun 17 18:58:53 PDT 2017
Introduced a common adjustable pll clock driver for Spreadtrum SoCs.
Original-by: Xiaolong Zhang <xiaolong.zhang at spreadtrum.com>
Signed-off-by: Chunyan Zhang <zhang.chunyan at linaro.org>
---
drivers/clk/sprd/Makefile | 2 +-
drivers/clk/sprd/ccu_pll.c | 241 +++++++++++++++++++++++++++++++++++++++++++++
drivers/clk/sprd/ccu_pll.h | 123 +++++++++++++++++++++++
3 files changed, 365 insertions(+), 1 deletion(-)
create mode 100644 drivers/clk/sprd/ccu_pll.c
create mode 100644 drivers/clk/sprd/ccu_pll.h
diff --git a/drivers/clk/sprd/Makefile b/drivers/clk/sprd/Makefile
index 83232e5..c593a93 100644
--- a/drivers/clk/sprd/Makefile
+++ b/drivers/clk/sprd/Makefile
@@ -1,3 +1,3 @@
ifneq ($(CONFIG_OF),)
-obj-y += ccu_common.o ccu_gate.o ccu_mux.o ccu_div.o ccu_composite.o
+obj-y += ccu_common.o ccu_gate.o ccu_mux.o ccu_div.o ccu_composite.o ccu_pll.o
endif
diff --git a/drivers/clk/sprd/ccu_pll.c b/drivers/clk/sprd/ccu_pll.c
new file mode 100644
index 0000000..6c908e4
--- /dev/null
+++ b/drivers/clk/sprd/ccu_pll.c
@@ -0,0 +1,241 @@
+/*
+ * Spreadtrum pll clock driver
+ *
+ * Copyright (C) 2015~2017 Spreadtrum, Inc.
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+
+#include "ccu_pll.h"
+
+#define CCU_PLL_1M 1000000
+#define CCU_PLL_10M (CCU_PLL_1M * 10)
+
+#define pindex(pll, member) \
+ (pll->factors[member].shift / (8 * sizeof(pll->regs[0])))
+
+#define pshift(pll, member) \
+ (pll->factors[member].shift % (8 * sizeof(pll->regs[0])))
+
+#define pwidth(pll, member) \
+ pll->factors[member].width
+
+#define pmask(pll, member) \
+ ((pwidth(pll, member)) ? \
+ GENMASK(pwidth(pll, member) + pshift(pll, member) - 1, \
+ pshift(pll, member)) : 0)
+
+#define pinternal(pll, cfg, member) \
+ (cfg[pindex(pll, member)] & pmask(pll, member))
+
+#define pinternal_val(pll, cfg, member) \
+ (pinternal(pll, cfg, member) >> pshift(pll, member))
+
+static unsigned long pll_get_refin_rate(struct ccu_pll *pll)
+{
+ u8 shift, index, refin_id = 3;
+ u32 mask;
+ const unsigned long refin[4] = { 2, 4, 13, 26 };
+
+ if (pwidth(pll, PLL_REFIN)) {
+ index = pindex(pll, PLL_REFIN);
+ shift = pshift(pll, PLL_REFIN);
+ mask = pmask(pll, PLL_REFIN);
+ refin_id = (ccu_pll_readl(pll, index) & mask) >> shift;
+ if (refin_id > 3)
+ refin_id = 3;
+ }
+
+ return refin[refin_id];
+}
+
+static u8 pll_get_ibias(unsigned long rate, const u64 *table)
+{
+ u64 i;
+ u8 num = table[0];
+
+ for (i = 0; i < num; i++)
+ if (rate <= table[i + 1])
+ break;
+
+ return i == num ? num - 1 : i;
+}
+
+static unsigned long ccu_pll_helper_recalc_rate(struct ccu_pll *pll,
+ unsigned long parent_rate)
+{
+ unsigned long rate, refin, k1, k2;
+ unsigned long kint = 0, nint;
+ u32 reg_num = pll->regs[0];
+ u32 *cfg;
+ u32 i;
+ u32 mask;
+
+ cfg = kcalloc(reg_num, sizeof(*cfg), GFP_KERNEL);
+ if (!cfg)
+ return -ENOMEM;
+
+ for (i = 0; i < reg_num; i++)
+ cfg[i] = ccu_pll_readl(pll, i);
+
+ refin = pll_get_refin_rate(pll);
+
+ if (pinternal(pll, cfg, PLL_PREDIV))
+ refin = refin * 2;
+
+ if (pwidth(pll, PLL_POSTDIV) &&
+ ((pll->fflag == 1 && pinternal(pll, cfg, PLL_POSTDIV)) ||
+ (!pll->fflag && !pinternal(pll, cfg, PLL_POSTDIV))))
+ refin = refin / 2;
+
+ if (!pinternal(pll, cfg, PLL_DIV_S))
+ rate = refin * pinternal_val(pll, cfg, PLL_N) * CCU_PLL_10M;
+ else {
+ nint = pinternal_val(pll, cfg, PLL_NINT);
+ if (pinternal(pll, cfg, PLL_SDM_EN))
+ kint = pinternal_val(pll, cfg, PLL_KINT);
+
+ mask = pmask(pll, PLL_KINT);
+#ifdef CONFIG_64BIT
+ k1 = 1000;
+ k2 = 1000;
+ rate = DIV_ROUND_CLOSEST(refin * kint * k1,
+ ((mask >> __ffs(mask)) + 1)) *
+ k2 + refin * nint * CCU_PLL_1M;
+#else
+ k1 = 100;
+ k2 = 10000;
+ i = pwidth(pll, PLL_KINT);
+ i = i < 21 ? 0 : i - 21;
+ rate = DIV_ROUND_CLOSEST(refin * (kint >> i) * k1,
+ ((mask >> (__ffs(mask) + i)) + 1)) *
+ k2 + refin * nint * CCU_PLL_1M;
+#endif
+ }
+
+ return rate;
+}
+
+static int ccu_pll_helper_set_rate(struct ccu_pll *pll,
+ unsigned long rate,
+ unsigned long parent_rate)
+{
+ u32 mask, shift, width, ibias_val, index, kint, nint;
+ u32 reg_num = pll->regs[0], i = 0;
+ unsigned long refin, fvco = rate;
+ struct reg_cfg *cfg;
+
+ cfg = kcalloc(reg_num, sizeof(*cfg), GFP_KERNEL);
+ if (!cfg)
+ return -ENOMEM;
+
+ refin = pll_get_refin_rate(pll);
+
+ mask = pmask(pll, PLL_PREDIV);
+ index = pindex(pll, PLL_PREDIV);
+ width = pwidth(pll, PLL_PREDIV);
+ if (width && (ccu_pll_readl(pll, index) & mask))
+ refin = refin * 2;
+
+ mask = pmask(pll, PLL_POSTDIV);
+ index = pindex(pll, PLL_POSTDIV);
+ width = pwidth(pll, PLL_POSTDIV);
+ cfg[index].msk = mask;
+ if (width && ((pll->fflag == 1 && fvco <= pll->fvco) ||
+ (pll->fflag == 0 && fvco > pll->fvco)))
+ cfg[index].val |= mask;
+
+ if (width && fvco <= pll->fvco)
+ fvco = fvco * 2;
+
+ mask = pmask(pll, PLL_DIV_S);
+ index = pindex(pll, PLL_DIV_S);
+ cfg[index].val |= mask;
+ cfg[index].msk |= mask;
+
+ mask = pmask(pll, PLL_SDM_EN);
+ index = pindex(pll, PLL_SDM_EN);
+ cfg[index].val |= mask;
+ cfg[index].msk |= mask;
+
+ nint = fvco/(refin * CCU_PLL_1M);
+
+ mask = pmask(pll, PLL_NINT);
+ index = pindex(pll, PLL_NINT);
+ shift = pshift(pll, PLL_NINT);
+ cfg[index].val |= (nint << shift) & mask;
+ cfg[index].msk |= mask;
+
+ mask = pmask(pll, PLL_KINT);
+ index = pindex(pll, PLL_KINT);
+ width = pwidth(pll, PLL_KINT);
+ shift = pshift(pll, PLL_KINT);
+#ifndef CONFIG_64BIT
+ i = width < 21 ? 0 : i - 21;
+#endif
+ kint = DIV_ROUND_CLOSEST(((fvco - refin * nint * CCU_PLL_1M)/10000) *
+ ((mask >> (shift + i)) + 1), refin * 100) << i;
+ cfg[index].val |= (kint << shift) & mask;
+ cfg[index].msk |= mask;
+
+ ibias_val = pll_get_ibias(fvco, pll->itable);
+
+ mask = pmask(pll, PLL_IBIAS);
+ index = pindex(pll, PLL_IBIAS);
+ shift = pshift(pll, PLL_IBIAS);
+ cfg[index].val |= ibias_val << shift & mask;
+ cfg[index].msk |= mask;
+
+ for (i = 0; i < reg_num; i++) {
+ if (cfg[i].msk)
+ ccu_pll_writel(pll, i, cfg[i].val, cfg[i].msk);
+ }
+
+ udelay(pll->udelay);
+
+ return 0;
+}
+
+static unsigned long ccu_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct ccu_pll *pll = hw_to_ccu_pll(hw);
+
+ return ccu_pll_helper_recalc_rate(pll, parent_rate);
+}
+
+static int ccu_pll_set_rate(struct clk_hw *hw,
+ unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct ccu_pll *pll = hw_to_ccu_pll(hw);
+
+ return ccu_pll_helper_set_rate(pll, rate, parent_rate);
+}
+
+static int ccu_pll_clk_prepare(struct clk_hw *hw)
+{
+ struct ccu_pll *pll = hw_to_ccu_pll(hw);
+
+ udelay(pll->udelay);
+
+ return 0;
+}
+
+static long ccu_pll_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ return rate;
+}
+
+const struct clk_ops ccu_pll_ops = {
+ .prepare = ccu_pll_clk_prepare,
+ .recalc_rate = ccu_pll_recalc_rate,
+ .round_rate = ccu_pll_round_rate,
+ .set_rate = ccu_pll_set_rate,
+};
diff --git a/drivers/clk/sprd/ccu_pll.h b/drivers/clk/sprd/ccu_pll.h
new file mode 100644
index 0000000..66fe5d1
--- /dev/null
+++ b/drivers/clk/sprd/ccu_pll.h
@@ -0,0 +1,123 @@
+/*
+ * Spreadtrum clock pll configurations
+ *
+ * Copyright (C) 2015~2017 Spreadtrum, Inc.
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+#ifndef _CCU_PLL_H_
+#define _CCU_PLL_H_
+
+#include "ccu_common.h"
+
+struct reg_cfg {
+ u32 val;
+ u32 msk;
+};
+
+struct ccu_bit_field {
+ u8 shift;
+ u8 width;
+};
+
+enum {
+ PLL_LOCK_DONE = 0,
+ PLL_DIV_S,
+ PLL_MOD_EN,
+ PLL_SDM_EN,
+ PLL_REFIN,
+ PLL_IBIAS,
+ PLL_N,
+ PLL_NINT,
+ PLL_KINT,
+ PLL_PREDIV,
+ PLL_POSTDIV,
+
+ PLL_FACT_MAX
+};
+
+/*
+ * struct ccu_pll - defination of adjustable pll clock
+ *
+ * @reg: registers used to set the configuration of pll clock,
+ * reg[0] shows how many registers this pll clock uses.
+ * @itable: pll ibias table, itable[0] means how many items this
+ * table includes
+ * @udelay delay time after setting rate
+ * @factors used to calculate the pll clock rate
+ * @fvco: fvco threshold rate
+ * @fflag: fvco flag
+ */
+struct ccu_pll {
+ const u32 *regs;
+ const u64 *itable;
+ u16 udelay;
+ const struct ccu_bit_field *factors;
+ u64 fvco;
+ u16 fflag;
+
+ struct ccu_common common;
+};
+
+#define SPRD_CCU_PLL_WITH_ITABLE_FVCO(_struct, _name, _parent, _reg, \
+ _regs, _itable, _udelay, \
+ _factors, _fvco, _fflag) \
+ struct ccu_pll _struct = { \
+ .regs = _regs, \
+ .itable = _itable, \
+ .udelay = _udelay, \
+ .factors = _factors, \
+ .fvco = _fvco, \
+ .fflag = _fflag, \
+ .common = { \
+ .reg = _reg, \
+ .hw.init = CLK_HW_INIT(_name, \
+ _parent, \
+ &ccu_pll_ops, \
+ CLK_IGNORE_UNUSED), \
+ }, \
+ }
+
+#define SPRD_CCU_PLL_WITH_ITABLE(_struct, _name, _parent, _reg, \
+ _regs, _itable, _udelay, \
+ _factors) \
+ SPRD_CCU_PLL_WITH_ITABLE_FVCO(_struct, _name, _parent, _reg, \
+ _regs, _itable, _udelay, \
+ _factors, 0, 0)
+
+static inline struct ccu_pll *hw_to_ccu_pll(struct clk_hw *hw)
+{
+ struct ccu_common *common = hw_to_ccu_common(hw);
+
+ return container_of(common, struct ccu_pll, common);
+}
+
+static inline u32 ccu_pll_readl(struct ccu_pll *pll, u8 index)
+{
+ struct ccu_common *common = &pll->common;
+
+ if (WARN_ON(index >= pll->regs[0]))
+ return 0;
+
+ return readl(common->base + pll->regs[index + 1]);
+}
+
+static inline void ccu_pll_writel(struct ccu_pll *pll, u8 index,
+ u32 val, u32 msk)
+{
+ struct ccu_common *common = &pll->common;
+ void __iomem *addr;
+ u32 reg;
+
+ if (WARN_ON(index >= pll->regs[0]))
+ return;
+
+ addr = common->base + pll->regs[index + 1];
+ reg = readl(addr);
+ writel((reg & ~msk) | val, addr);
+}
+
+extern const struct clk_ops ccu_pll_ops;
+
+#endif /* _CCU_PLL_H_ */
--
2.7.4
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