clk: rockchip: add clock type for pll clocks and pll used on rk3066

A patch from »Add real clock support for Rockchip's RK3188« in state Mainline for linux-kernel

From: Heiko Stuebner <heiko@...> Date: Thu, 10 Apr 2014 15:09:38 +0200

Commit-Message

All known Rockchip SoCs down to the RK28xx (ARM9) use a similar pattern to handle plls. 1 or more pll-dependant setting registers, a shared pll mode register and the pll lock status in a register somewhere else. Therefore add shared infrastructure to handle the common pll actions and also the pll type used in rk3066 and rk3188 Cortex-A9 SoCs. Signed-off-by: Heiko Stuebner <heiko@...>

Patch-Comment

drivers/clk/rockchip/Makefile | 1 + drivers/clk/rockchip/clk-pll.c | 317 +++++++++++++++++++++++++++++++++++++++++ drivers/clk/rockchip/clk.c | 19 +++ drivers/clk/rockchip/clk.h | 66 +++++++++ 4 files changed, 403 insertions(+) create mode 100644 drivers/clk/rockchip/clk-pll.c

Statistics

  • 403 lines added
  • 0 lines removed

Changes

------------------------ drivers/clk/rockchip/Makefile -------------------------
index 0068a8b..2cb9164 100644
@@ -4,3 +4,4 @@
obj-y += clk-rockchip.o
obj-y += clk.o
+obj-y += clk-pll.o
------------------------ drivers/clk/rockchip/clk-pll.c ------------------------
new file mode 100644
index 0000000..14820d5
@@ -0,0 +1,317 @@
+/*
+ * Copyright (c) 2014 MundoReader S.L.
+ * Author: Heiko Stuebner <heiko@sntech.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <asm/div64.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/clk-private.h>
+#include "clk.h"
+
+struct rockchip_clk_pll {
+ struct clk_hw hw;
+ void __iomem *reg_base;
+ void __iomem *reg_mode;
+ unsigned int mode_shift;
+ void __iomem *reg_lock;
+ unsigned int lock_shift;
+ enum rockchip_pll_type type;
+ const struct rockchip_pll_rate_table *rate_table;
+ unsigned int rate_count;
+ spinlock_t *lock;
+};
+
+#define to_clk_pll(_hw) container_of(_hw, struct rockchip_clk_pll, hw)
+
+static const struct rockchip_pll_rate_table *rockchip_get_pll_settings(
+ struct rockchip_clk_pll *pll, unsigned long rate)
+{
+ const struct rockchip_pll_rate_table *rate_table = pll->rate_table;
+ int i;
+
+ for (i = 0; i < pll->rate_count; i++) {
+ if (rate == rate_table[i].rate)
+ return &rate_table[i];
+ }
+
+ return NULL;
+}
+
+static long rockchip_pll_round_rate(struct clk_hw *hw,
+ unsigned long drate, unsigned long *prate)
+{
+ struct rockchip_clk_pll *pll = to_clk_pll(hw);
+ const struct rockchip_pll_rate_table *rate_table = pll->rate_table;
+ int i;
+
+ /*
+ * For anything smaller or equal to the parent rate, we can only
+ * bypass the pll, so the parent_rate is the lowest we can get.
+ */
+ if (drate <= *prate)
+ return *prate;
+
+ /* Assumming rate_table is in descending order */
+ for (i = 0; i < pll->rate_count; i++) {
+ if (drate >= rate_table[i].rate)
+ return rate_table[i].rate;
+ }
+
+ /* return minimum supported value */
+ return rate_table[i - 1].rate;
+}
+
+static int rockchip_pll_wait_lock(struct rockchip_clk_pll *pll)
+{
+ int delay = 24000000;
+
+ while (delay > 0) {
+ if (readl(pll->reg_lock) & BIT(pll->lock_shift))
+ return 0;
+ delay--;
+ }
+
+ pr_err("%s: timeout waiting for pll to lock\n", __func__);
+ return -ETIMEDOUT;
+}
+
+/**
+ * PLL used in RK3066 and RK3188
+ */
+
+#define RK3066_PLL_MODE_MASK 0x3
+#define RK3066_PLL_MODE_SLOW 0x0
+#define RK3066_PLL_MODE_NORM 0x1
+#define RK3066_PLL_MODE_DEEP 0x2
+
+#define RK3066_PLL_RESET_DELAY(nr) ((nr * 500) / 24 + 1)
+
+#define RK3066_PLLCON(i) (i * 0x4)
+
+#define RK3066_PLLCON0_OD_MASK 0xf
+#define RK3066_PLLCON0_OD_SHIFT 0
+#define RK3066_PLLCON0_NR_MASK 0x3f
+#define RK3066_PLLCON0_NR_SHIFT 8
+
+#define RK3066_PLLCON1_NF_MASK 0x1fff
+#define RK3066_PLLCON1_NF_SHIFT 0
+
+#define RK3066_PLLCON2_BWADJ_MASK 0xfff
+#define RK3066_PLLCON2_BWADJ_SHIFT 0
+
+#define RK3066_PLLCON3_RESET (1 << 5)
+#define RK3066_PLLCON3_PWRDOWN (1 << 1)
+#define RK3066_PLLCON3_BYPASS (1 << 0)
+
+static unsigned long rockchip_rk3066_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long prate)
+{
+ struct rockchip_clk_pll *pll = to_clk_pll(hw);
+ u64 nf, nr, no, rate64 = prate;
+ u32 pllcon;
+
+ pllcon = readl_relaxed(pll->reg_base + RK3066_PLLCON(3));
+ if (pllcon & RK3066_PLLCON3_BYPASS) {
+ pr_debug("%s: pll %s is bypassed\n", __func__,
+ __clk_get_name(hw->clk));
+ return prate;
+ }
+
+ pllcon = readl_relaxed(pll->reg_mode) >> pll->mode_shift;
+ pllcon &= RK3066_PLL_MODE_MASK;
+ switch (pllcon) {
+ case RK3066_PLL_MODE_NORM:
+ /* calculate the PLL rate below */
+ break;
+ case RK3066_PLL_MODE_SLOW:
+ return prate;
+ case RK3066_PLL_MODE_DEEP:
+ pr_warn("%s: deep slow mode for pll %s currently unknown, assuming parent rate\n",
+ __func__, __clk_get_name(hw->clk));
+ return prate;
+ }
+
+ pllcon = readl_relaxed(pll->reg_base + RK3066_PLLCON(1));
+ nf = (pllcon >> RK3066_PLLCON1_NF_SHIFT) & RK3066_PLLCON1_NF_MASK;
+
+ pllcon = readl_relaxed(pll->reg_base + RK3066_PLLCON(0));
+ nr = (pllcon >> RK3066_PLLCON0_NR_SHIFT) & RK3066_PLLCON0_NR_MASK;
+ no = (pllcon >> RK3066_PLLCON0_OD_SHIFT) & RK3066_PLLCON0_OD_MASK;
+
+ rate64 *= (nf + 1);
+ do_div(rate64, nr + 1);
+ do_div(rate64, no + 1);
+
+ return (unsigned long)rate64;
+}
+
+static int rockchip_rk3066_pll_set_rate(struct clk_hw *hw, unsigned long drate,
+ unsigned long prate)
+{
+ struct rockchip_clk_pll *pll = to_clk_pll(hw);
+ const struct rockchip_pll_rate_table *rate;
+ unsigned long old_rate = rockchip_rk3066_pll_recalc_rate(hw, prate);
+ int ret;
+
+ pr_debug("%s: changing %s from %lu to %lu with a parent rate of %lu\n",
+ __func__, __clk_get_name(hw->clk), old_rate, drate, prate);
+
+ if (drate == prate) {
+ writel(HIWORD_UPDATE(RK3066_PLL_MODE_SLOW, RK3066_PLL_MODE_MASK,
+ pll->mode_shift),
+ pll->reg_mode);
+
+ /* powerdown the pll, as it is unused */
+ writel(HIWORD_UPDATE(RK3066_PLLCON3_PWRDOWN,
+ RK3066_PLLCON3_PWRDOWN, 0),
+ pll->reg_base + RK3066_PLLCON(3));
+
+ return 0;
+ }
+
+ /* need to powerup the pll first */
+ if (old_rate == prate)
+ writel(HIWORD_UPDATE(0, RK3066_PLLCON3_PWRDOWN, 0),
+ pll->reg_base + RK3066_PLLCON(3));
+
+ /* Get required rate settings from table */
+ rate = rockchip_get_pll_settings(pll, drate);
+ if (!rate) {
+ pr_err("%s: Invalid rate : %lu for pll clk %s\n", __func__,
+ drate, __clk_get_name(hw->clk));
+ return -EINVAL;
+ }
+
+ pr_debug("%s: rate settings for %lu (nr, no, nf): (%d, %d, %d)\n",
+ __func__, rate->rate, rate->nr, rate->no, rate->nf);
+
+ /* put pll in slow mode and enter reset afterwards */
+ writel_relaxed(HIWORD_UPDATE(RK3066_PLL_MODE_SLOW, RK3066_PLL_MODE_MASK,
+ pll->mode_shift), pll->reg_mode);
+ writel(HIWORD_UPDATE(RK3066_PLLCON3_RESET, RK3066_PLLCON3_RESET, 0),
+ pll->reg_base + RK3066_PLLCON(3));
+
+ /* update pll values */
+ writel(HIWORD_UPDATE(rate->nr - 1, RK3066_PLLCON0_NR_MASK,
+ RK3066_PLLCON0_NR_SHIFT) |
+ HIWORD_UPDATE(rate->no - 1, RK3066_PLLCON0_OD_MASK,
+ RK3066_PLLCON0_OD_SHIFT),
+ pll->reg_base + RK3066_PLLCON(0));
+
+ writel_relaxed(HIWORD_UPDATE(rate->nf - 1, RK3066_PLLCON1_NF_MASK,
+ RK3066_PLLCON1_NF_SHIFT),
+ pll->reg_base + RK3066_PLLCON(1));
+ writel_relaxed(HIWORD_UPDATE((rate->nf >> 1),
+ RK3066_PLLCON2_BWADJ_MASK,
+ RK3066_PLLCON2_BWADJ_SHIFT),
+ pll->reg_base + RK3066_PLLCON(2));
+
+ /* leave reset and wait the reset_delay */
+ writel(HIWORD_UPDATE(0, RK3066_PLLCON3_RESET, 0),
+ pll->reg_base + RK3066_PLLCON(3));
+ udelay(RK3066_PLL_RESET_DELAY(rate->nr));
+
+ /* wait for the pll to lock */
+ ret = rockchip_pll_wait_lock(pll);
+ if (ret) {
+ pr_warn("%s: trying to restore old rate %lu\n",
+ __func__, old_rate);
+ rockchip_rk3066_pll_set_rate(hw, old_rate, prate);
+ }
+
+ /* go back to normal mode */
+ writel(HIWORD_UPDATE(RK3066_PLL_MODE_NORM, RK3066_PLL_MODE_MASK,
+ pll->mode_shift), pll->reg_mode);
+
+ return ret;
+}
+
+static const struct clk_ops rockchip_rk3066_pll_clk_ro_ops = {
+ .recalc_rate = rockchip_rk3066_pll_recalc_rate,
+};
+
+static const struct clk_ops rockchip_rk3066_pll_clk_ops = {
+ .recalc_rate = rockchip_rk3066_pll_recalc_rate,
+ .round_rate = rockchip_pll_round_rate,
+ .set_rate = rockchip_rk3066_pll_set_rate,
+};
+
+struct clk *rockchip_clk_register_pll(struct rockchip_pll_clock *pll_clk,
+ void __iomem *base, void __iomem *reg_lock,
+ spinlock_t *lock)
+{
+ struct rockchip_clk_pll *pll;
+ struct clk *clk;
+ struct clk_init_data init;
+ int len;
+
+ pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+ if (!pll) {
+ pr_err("%s: could not allocate pll clk %s\n",
+ __func__, pll_clk->name);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ init.name = pll_clk->name;
+ init.flags = pll_clk->flags;
+ init.parent_names = &pll_clk->parent_name;
+ init.num_parents = 1;
+
+ if (pll_clk->rate_table) {
+ /* find count of rates in rate_table */
+ for (len = 0; pll_clk->rate_table[len].rate != 0; )
+ len++;
+
+ pll->rate_count = len;
+ pll->rate_table = kmemdup(pll_clk->rate_table,
+ pll->rate_count *
+ sizeof(struct rockchip_pll_rate_table),
+ GFP_KERNEL);
+ WARN(!pll->rate_table,
+ "%s: could not allocate rate table for %s\n",
+ __func__, pll_clk->name);
+ }
+
+ switch (pll_clk->type) {
+ case pll_rk3066:
+ if (!pll->rate_table)
+ init.ops = &rockchip_rk3066_pll_clk_ro_ops;
+ else
+ init.ops = &rockchip_rk3066_pll_clk_ops;
+ break;
+ default:
+ pr_warn("%s: Unknown pll type for pll clk %s\n",
+ __func__, pll_clk->name);
+ }
+
+ pll->hw.init = &init;
+ pll->type = pll_clk->type;
+ pll->reg_base = base + pll_clk->con_offset;
+ pll->reg_mode = base + pll_clk->mode_offset;
+ pll->mode_shift = pll_clk->mode_shift;
+ pll->reg_lock = reg_lock;
+ pll->lock_shift = pll_clk->lock_shift;
+ pll->lock = lock;
+
+ clk = clk_register(NULL, &pll->hw);
+ if (IS_ERR(clk)) {
+ pr_err("%s: failed to register pll clock %s : %ld\n",
+ __func__, pll_clk->name, PTR_ERR(clk));
+ kfree(pll);
+ }
+
+ return clk;
+}
-------------------------- drivers/clk/rockchip/clk.c --------------------------
index b71413e..53e604d 100644
@@ -55,6 +55,25 @@ void rockchip_clk_add_lookup(struct clk *clk, unsigned int id)
clk_table[id] = clk;
}
+void __init rockchip_clk_register_plls(struct rockchip_pll_clock *list,
+ unsigned int nr_pll, void __iomem *reg_lock)
+{
+ struct clk *clk;
+ int idx;
+
+ for (idx = 0; idx < nr_pll; idx++, list++) {
+ clk = rockchip_clk_register_pll(list, reg_base, reg_lock,
+ &clk_lock);
+ if (IS_ERR(clk)) {
+ pr_err("%s: failed to register clock %s\n", __func__,
+ list->name);
+ continue;
+ }
+
+ rockchip_clk_add_lookup(clk, list->id);
+ }
+}
+
void __init rockchip_clk_register_mux(struct rockchip_mux_clock *list,
unsigned int nr_clk)
{
-------------------------- drivers/clk/rockchip/clk.h --------------------------
index 2b42c8b..fdb63c2 100644
@@ -39,6 +39,70 @@
#define RK2928_GLB_SRST_SND 0x104
#define RK2928_SOFTRST_CON(x) (x * 0x4 + 0x110)
+enum rockchip_pll_type {
+ pll_rk3066,
+};
+
+#define RK3066_PLL_RATE(_rate, _nr, _nf, _no) \
+{ \
+ .rate = _rate##U, \
+ .nr = _nr, \
+ .nf = _nf, \
+ .no = _no, \
+}
+
+struct rockchip_pll_rate_table {
+ unsigned long rate;
+ unsigned int nr;
+ unsigned int nf;
+ unsigned int no;
+};
+
+/**
+ * struct rockchip_pll_clock: information about pll clock
+ * @id: platform specific id of the clock.
+ * @name: name of this pll clock.
+ * @parent_name: name of the parent clock.
+ * @flags: optional flags for basic clock.
+ * @con_offset: offset of the register for configuring the PLL.
+ * @mode_offset: offset of the register for configuring the PLL-mode.
+ * @mode_shift: offset inside the mode-register for the mode of this pll.
+ * @lock_shift: offset inside the lock register for the lock status.
+ * @type: Type of PLL to be registered.
+ * @rate_table: Table of usable pll rates
+ */
+struct rockchip_pll_clock {
+ unsigned int id;
+ const char *name;
+ const char *parent_name;
+ unsigned long flags;
+ int con_offset;
+ int mode_offset;
+ int mode_shift;
+ int lock_shift;
+ enum rockchip_pll_type type;
+ const struct rockchip_pll_rate_table *rate_table;
+};
+
+#define PLL(_type, _id, _name, _pname, _flags, _con, _mode, _mshift, \
+ _lshift, _rtable) \
+ { \
+ .id = _id, \
+ .type = _type, \
+ .name = _name, \
+ .parent_name = _pname, \
+ .flags = CLK_GET_RATE_NOCACHE | _flags, \
+ .con_offset = _con, \
+ .mode_offset = _mode, \
+ .mode_shift = _mshift, \
+ .lock_shift = _lshift, \
+ .rate_table = _rtable, \
+ }
+
+struct clk *rockchip_clk_register_pll(struct rockchip_pll_clock *pll_clk,
+ void __iomem *base, void __iomem *reg_lock,
+ spinlock_t *lock);
+
#define PNAME(x) static const char *x[] __initconst
/**
@@ -156,5 +220,7 @@ void rockchip_clk_register_div(struct rockchip_div_clock *clk_list,
unsigned int nr_clk);
void rockchip_clk_register_gate(struct rockchip_gate_clock *clk_list,
unsigned int nr_clk);
+void rockchip_clk_register_plls(struct rockchip_pll_clock *pll_list,
+ unsigned int nr_pll, void __iomem *reg_lock);
#endif
 
 

Recent Patches

About Us

Sed lacus. Donec lectus. Nullam pretium nibh ut turpis. Nam bibendum. In nulla tortor, elementum vel, tempor at, varius non, purus. Mauris vitae nisl nec metus placerat consectetuer.

Read More...