Introduced a common adjustable pll clock driver for Spreadtrum SoCs.

Original-by: Xiaolong Zhang <xiaolong.zh...@spreadtrum.com>
Signed-off-by: Chunyan Zhang <zhang.chun...@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

Reply via email to