summaryrefslogtreecommitdiffstats
path: root/drivers/clk/sprd/pll.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--drivers/clk/sprd/pll.c269
1 files changed, 269 insertions, 0 deletions
diff --git a/drivers/clk/sprd/pll.c b/drivers/clk/sprd/pll.c
new file mode 100644
index 000000000..13a322b25
--- /dev/null
+++ b/drivers/clk/sprd/pll.c
@@ -0,0 +1,269 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Spreadtrum pll clock driver
+//
+// Copyright (C) 2015~2017 Spreadtrum, Inc.
+// Author: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#include "pll.h"
+
+#define CLK_PLL_1M 1000000
+#define CLK_PLL_10M (CLK_PLL_1M * 10)
+
+#define pindex(pll, member) \
+ (pll->factors[member].shift / (8 * sizeof(pll->regs_num)))
+
+#define pshift(pll, member) \
+ (pll->factors[member].shift % (8 * sizeof(pll->regs_num)))
+
+#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 inline unsigned int
+sprd_pll_read(const struct sprd_pll *pll, u8 index)
+{
+ const struct sprd_clk_common *common = &pll->common;
+ unsigned int val = 0;
+
+ if (WARN_ON(index >= pll->regs_num))
+ return 0;
+
+ regmap_read(common->regmap, common->reg + index * 4, &val);
+
+ return val;
+}
+
+static inline void
+sprd_pll_write(const struct sprd_pll *pll, u8 index,
+ u32 msk, u32 val)
+{
+ const struct sprd_clk_common *common = &pll->common;
+ unsigned int offset, reg;
+ int ret = 0;
+
+ if (WARN_ON(index >= pll->regs_num))
+ return;
+
+ offset = common->reg + index * 4;
+ ret = regmap_read(common->regmap, offset, &reg);
+ if (!ret)
+ regmap_write(common->regmap, offset, (reg & ~msk) | val);
+}
+
+static unsigned long pll_get_refin(const struct sprd_pll *pll)
+{
+ u32 shift, mask, index, refin_id = 3;
+ 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 = (sprd_pll_read(pll, index) & mask) >> shift;
+ if (refin_id > 3)
+ refin_id = 3;
+ }
+
+ return refin[refin_id];
+}
+
+static u32 pll_get_ibias(u64 rate, const u64 *table)
+{
+ u32 i, num = table[0];
+
+ /* table[0] indicates the number of items in this table */
+ for (i = 0; i < num; i++)
+ if (rate <= table[i + 1])
+ break;
+
+ return i == num ? num - 1 : i;
+}
+
+static unsigned long _sprd_pll_recalc_rate(const struct sprd_pll *pll,
+ unsigned long parent_rate)
+{
+ u32 *cfg;
+ u32 i, mask, regs_num = pll->regs_num;
+ unsigned long rate, nint, kint = 0;
+ u64 refin;
+ u16 k1, k2;
+
+ cfg = kcalloc(regs_num, sizeof(*cfg), GFP_KERNEL);
+ if (!cfg)
+ return parent_rate;
+
+ for (i = 0; i < regs_num; i++)
+ cfg[i] = sprd_pll_read(pll, i);
+
+ refin = pll_get_refin(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) * CLK_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);
+
+ k1 = pll->k1;
+ k2 = pll->k2;
+ rate = DIV_ROUND_CLOSEST_ULL(refin * kint * k1,
+ ((mask >> __ffs(mask)) + 1)) *
+ k2 + refin * nint * CLK_PLL_1M;
+ }
+
+ kfree(cfg);
+ return rate;
+}
+
+#define SPRD_PLL_WRITE_CHECK(pll, i, mask, val) \
+ (((sprd_pll_read(pll, i) & mask) == val) ? 0 : (-EFAULT))
+
+static int _sprd_pll_set_rate(const struct sprd_pll *pll,
+ unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct reg_cfg *cfg;
+ int ret = 0;
+ u32 mask, shift, width, ibias_val, index;
+ u32 regs_num = pll->regs_num, i = 0;
+ unsigned long kint, nint;
+ u64 tmp, refin, fvco = rate;
+
+ cfg = kcalloc(regs_num, sizeof(*cfg), GFP_KERNEL);
+ if (!cfg)
+ return -ENOMEM;
+
+ refin = pll_get_refin(pll);
+
+ mask = pmask(pll, PLL_PREDIV);
+ index = pindex(pll, PLL_PREDIV);
+ width = pwidth(pll, PLL_PREDIV);
+ if (width && (sprd_pll_read(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 = do_div(fvco, refin * CLK_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);
+ tmp = fvco - refin * nint * CLK_PLL_1M;
+ tmp = do_div(tmp, 10000) * ((mask >> shift) + 1);
+ kint = DIV_ROUND_CLOSEST_ULL(tmp, refin * 100);
+ 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 < regs_num; i++) {
+ if (cfg[i].msk) {
+ sprd_pll_write(pll, i, cfg[i].msk, cfg[i].val);
+ ret |= SPRD_PLL_WRITE_CHECK(pll, i, cfg[i].msk,
+ cfg[i].val);
+ }
+ }
+
+ if (!ret)
+ udelay(pll->udelay);
+
+ kfree(cfg);
+ return ret;
+}
+
+static unsigned long sprd_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct sprd_pll *pll = hw_to_sprd_pll(hw);
+
+ return _sprd_pll_recalc_rate(pll, parent_rate);
+}
+
+static int sprd_pll_set_rate(struct clk_hw *hw,
+ unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct sprd_pll *pll = hw_to_sprd_pll(hw);
+
+ return _sprd_pll_set_rate(pll, rate, parent_rate);
+}
+
+static int sprd_pll_clk_prepare(struct clk_hw *hw)
+{
+ struct sprd_pll *pll = hw_to_sprd_pll(hw);
+
+ udelay(pll->udelay);
+
+ return 0;
+}
+
+static long sprd_pll_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ return rate;
+}
+
+const struct clk_ops sprd_pll_ops = {
+ .prepare = sprd_pll_clk_prepare,
+ .recalc_rate = sprd_pll_recalc_rate,
+ .round_rate = sprd_pll_round_rate,
+ .set_rate = sprd_pll_set_rate,
+};
+EXPORT_SYMBOL_GPL(sprd_pll_ops);