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path: root/drivers/clk/bcm/clk-iproc-pll.c
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-rw-r--r--drivers/clk/bcm/clk-iproc-pll.c863
1 files changed, 863 insertions, 0 deletions
diff --git a/drivers/clk/bcm/clk-iproc-pll.c b/drivers/clk/bcm/clk-iproc-pll.c
new file mode 100644
index 0000000000..680f9d8d35
--- /dev/null
+++ b/drivers/clk/bcm/clk-iproc-pll.c
@@ -0,0 +1,863 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (C) 2014 Broadcom Corporation
+
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/clkdev.h>
+#include <linux/of_address.h>
+#include <linux/delay.h>
+
+#include "clk-iproc.h"
+
+#define PLL_VCO_HIGH_SHIFT 19
+#define PLL_VCO_LOW_SHIFT 30
+
+/*
+ * PLL MACRO_SELECT modes 0 to 5 choose pre-calculated PLL output frequencies
+ * from a look-up table. Mode 7 allows user to manipulate PLL clock dividers
+ */
+#define PLL_USER_MODE 7
+
+/* number of delay loops waiting for PLL to lock */
+#define LOCK_DELAY 100
+
+/* number of VCO frequency bands */
+#define NUM_FREQ_BANDS 8
+
+#define NUM_KP_BANDS 3
+enum kp_band {
+ KP_BAND_MID = 0,
+ KP_BAND_HIGH,
+ KP_BAND_HIGH_HIGH
+};
+
+static const unsigned int kp_table[NUM_KP_BANDS][NUM_FREQ_BANDS] = {
+ { 5, 6, 6, 7, 7, 8, 9, 10 },
+ { 4, 4, 5, 5, 6, 7, 8, 9 },
+ { 4, 5, 5, 6, 7, 8, 9, 10 },
+};
+
+static const unsigned long ref_freq_table[NUM_FREQ_BANDS][2] = {
+ { 10000000, 12500000 },
+ { 12500000, 15000000 },
+ { 15000000, 20000000 },
+ { 20000000, 25000000 },
+ { 25000000, 50000000 },
+ { 50000000, 75000000 },
+ { 75000000, 100000000 },
+ { 100000000, 125000000 },
+};
+
+enum vco_freq_range {
+ VCO_LOW = 700000000U,
+ VCO_MID = 1200000000U,
+ VCO_HIGH = 2200000000U,
+ VCO_HIGH_HIGH = 3100000000U,
+ VCO_MAX = 4000000000U,
+};
+
+struct iproc_pll {
+ void __iomem *status_base;
+ void __iomem *control_base;
+ void __iomem *pwr_base;
+ void __iomem *asiu_base;
+
+ const struct iproc_pll_ctrl *ctrl;
+ const struct iproc_pll_vco_param *vco_param;
+ unsigned int num_vco_entries;
+};
+
+struct iproc_clk {
+ struct clk_hw hw;
+ struct iproc_pll *pll;
+ const struct iproc_clk_ctrl *ctrl;
+};
+
+#define to_iproc_clk(hw) container_of(hw, struct iproc_clk, hw)
+
+static int pll_calc_param(unsigned long target_rate,
+ unsigned long parent_rate,
+ struct iproc_pll_vco_param *vco_out)
+{
+ u64 ndiv_int, ndiv_frac, residual;
+
+ ndiv_int = target_rate / parent_rate;
+
+ if (!ndiv_int || (ndiv_int > 255))
+ return -EINVAL;
+
+ residual = target_rate - (ndiv_int * parent_rate);
+ residual <<= 20;
+
+ /*
+ * Add half of the divisor so the result will be rounded to closest
+ * instead of rounded down.
+ */
+ residual += (parent_rate / 2);
+ ndiv_frac = div64_u64((u64)residual, (u64)parent_rate);
+
+ vco_out->ndiv_int = ndiv_int;
+ vco_out->ndiv_frac = ndiv_frac;
+ vco_out->pdiv = 1;
+
+ vco_out->rate = vco_out->ndiv_int * parent_rate;
+ residual = (u64)vco_out->ndiv_frac * (u64)parent_rate;
+ residual >>= 20;
+ vco_out->rate += residual;
+
+ return 0;
+}
+
+/*
+ * Based on the target frequency, find a match from the VCO frequency parameter
+ * table and return its index
+ */
+static int pll_get_rate_index(struct iproc_pll *pll, unsigned int target_rate)
+{
+ int i;
+
+ for (i = 0; i < pll->num_vco_entries; i++)
+ if (target_rate == pll->vco_param[i].rate)
+ break;
+
+ if (i >= pll->num_vco_entries)
+ return -EINVAL;
+
+ return i;
+}
+
+static int get_kp(unsigned long ref_freq, enum kp_band kp_index)
+{
+ int i;
+
+ if (ref_freq < ref_freq_table[0][0])
+ return -EINVAL;
+
+ for (i = 0; i < NUM_FREQ_BANDS; i++) {
+ if (ref_freq >= ref_freq_table[i][0] &&
+ ref_freq < ref_freq_table[i][1])
+ return kp_table[kp_index][i];
+ }
+ return -EINVAL;
+}
+
+static int pll_wait_for_lock(struct iproc_pll *pll)
+{
+ int i;
+ const struct iproc_pll_ctrl *ctrl = pll->ctrl;
+
+ for (i = 0; i < LOCK_DELAY; i++) {
+ u32 val = readl(pll->status_base + ctrl->status.offset);
+
+ if (val & (1 << ctrl->status.shift))
+ return 0;
+ udelay(10);
+ }
+
+ return -EIO;
+}
+
+static void iproc_pll_write(const struct iproc_pll *pll, void __iomem *base,
+ const u32 offset, u32 val)
+{
+ const struct iproc_pll_ctrl *ctrl = pll->ctrl;
+
+ writel(val, base + offset);
+
+ if (unlikely(ctrl->flags & IPROC_CLK_NEEDS_READ_BACK &&
+ (base == pll->status_base || base == pll->control_base)))
+ val = readl(base + offset);
+}
+
+static void __pll_disable(struct iproc_pll *pll)
+{
+ const struct iproc_pll_ctrl *ctrl = pll->ctrl;
+ u32 val;
+
+ if (ctrl->flags & IPROC_CLK_PLL_ASIU) {
+ val = readl(pll->asiu_base + ctrl->asiu.offset);
+ val &= ~(1 << ctrl->asiu.en_shift);
+ iproc_pll_write(pll, pll->asiu_base, ctrl->asiu.offset, val);
+ }
+
+ if (ctrl->flags & IPROC_CLK_EMBED_PWRCTRL) {
+ val = readl(pll->control_base + ctrl->aon.offset);
+ val |= bit_mask(ctrl->aon.pwr_width) << ctrl->aon.pwr_shift;
+ iproc_pll_write(pll, pll->control_base, ctrl->aon.offset, val);
+ }
+
+ if (pll->pwr_base) {
+ /* latch input value so core power can be shut down */
+ val = readl(pll->pwr_base + ctrl->aon.offset);
+ val |= 1 << ctrl->aon.iso_shift;
+ iproc_pll_write(pll, pll->pwr_base, ctrl->aon.offset, val);
+
+ /* power down the core */
+ val &= ~(bit_mask(ctrl->aon.pwr_width) << ctrl->aon.pwr_shift);
+ iproc_pll_write(pll, pll->pwr_base, ctrl->aon.offset, val);
+ }
+}
+
+static int __pll_enable(struct iproc_pll *pll)
+{
+ const struct iproc_pll_ctrl *ctrl = pll->ctrl;
+ u32 val;
+
+ if (ctrl->flags & IPROC_CLK_EMBED_PWRCTRL) {
+ val = readl(pll->control_base + ctrl->aon.offset);
+ val &= ~(bit_mask(ctrl->aon.pwr_width) << ctrl->aon.pwr_shift);
+ iproc_pll_write(pll, pll->control_base, ctrl->aon.offset, val);
+ }
+
+ if (pll->pwr_base) {
+ /* power up the PLL and make sure it's not latched */
+ val = readl(pll->pwr_base + ctrl->aon.offset);
+ val |= bit_mask(ctrl->aon.pwr_width) << ctrl->aon.pwr_shift;
+ val &= ~(1 << ctrl->aon.iso_shift);
+ iproc_pll_write(pll, pll->pwr_base, ctrl->aon.offset, val);
+ }
+
+ /* certain PLLs also need to be ungated from the ASIU top level */
+ if (ctrl->flags & IPROC_CLK_PLL_ASIU) {
+ val = readl(pll->asiu_base + ctrl->asiu.offset);
+ val |= (1 << ctrl->asiu.en_shift);
+ iproc_pll_write(pll, pll->asiu_base, ctrl->asiu.offset, val);
+ }
+
+ return 0;
+}
+
+static void __pll_put_in_reset(struct iproc_pll *pll)
+{
+ u32 val;
+ const struct iproc_pll_ctrl *ctrl = pll->ctrl;
+ const struct iproc_pll_reset_ctrl *reset = &ctrl->reset;
+
+ val = readl(pll->control_base + reset->offset);
+ if (ctrl->flags & IPROC_CLK_PLL_RESET_ACTIVE_LOW)
+ val |= BIT(reset->reset_shift) | BIT(reset->p_reset_shift);
+ else
+ val &= ~(BIT(reset->reset_shift) | BIT(reset->p_reset_shift));
+ iproc_pll_write(pll, pll->control_base, reset->offset, val);
+}
+
+static void __pll_bring_out_reset(struct iproc_pll *pll, unsigned int kp,
+ unsigned int ka, unsigned int ki)
+{
+ u32 val;
+ const struct iproc_pll_ctrl *ctrl = pll->ctrl;
+ const struct iproc_pll_reset_ctrl *reset = &ctrl->reset;
+ const struct iproc_pll_dig_filter_ctrl *dig_filter = &ctrl->dig_filter;
+
+ val = readl(pll->control_base + dig_filter->offset);
+ val &= ~(bit_mask(dig_filter->ki_width) << dig_filter->ki_shift |
+ bit_mask(dig_filter->kp_width) << dig_filter->kp_shift |
+ bit_mask(dig_filter->ka_width) << dig_filter->ka_shift);
+ val |= ki << dig_filter->ki_shift | kp << dig_filter->kp_shift |
+ ka << dig_filter->ka_shift;
+ iproc_pll_write(pll, pll->control_base, dig_filter->offset, val);
+
+ val = readl(pll->control_base + reset->offset);
+ if (ctrl->flags & IPROC_CLK_PLL_RESET_ACTIVE_LOW)
+ val &= ~(BIT(reset->reset_shift) | BIT(reset->p_reset_shift));
+ else
+ val |= BIT(reset->reset_shift) | BIT(reset->p_reset_shift);
+ iproc_pll_write(pll, pll->control_base, reset->offset, val);
+}
+
+/*
+ * Determines if the change to be applied to the PLL is minor (just an update
+ * or the fractional divider). If so, then we can avoid going through a
+ * disruptive reset and lock sequence.
+ */
+static bool pll_fractional_change_only(struct iproc_pll *pll,
+ struct iproc_pll_vco_param *vco)
+{
+ const struct iproc_pll_ctrl *ctrl = pll->ctrl;
+ u32 val;
+ u32 ndiv_int;
+ unsigned int pdiv;
+
+ /* PLL needs to be locked */
+ val = readl(pll->status_base + ctrl->status.offset);
+ if ((val & (1 << ctrl->status.shift)) == 0)
+ return false;
+
+ val = readl(pll->control_base + ctrl->ndiv_int.offset);
+ ndiv_int = (val >> ctrl->ndiv_int.shift) &
+ bit_mask(ctrl->ndiv_int.width);
+
+ if (ndiv_int != vco->ndiv_int)
+ return false;
+
+ val = readl(pll->control_base + ctrl->pdiv.offset);
+ pdiv = (val >> ctrl->pdiv.shift) & bit_mask(ctrl->pdiv.width);
+
+ if (pdiv != vco->pdiv)
+ return false;
+
+ return true;
+}
+
+static int pll_set_rate(struct iproc_clk *clk, struct iproc_pll_vco_param *vco,
+ unsigned long parent_rate)
+{
+ struct iproc_pll *pll = clk->pll;
+ const struct iproc_pll_ctrl *ctrl = pll->ctrl;
+ int ka = 0, ki, kp, ret;
+ unsigned long rate = vco->rate;
+ u32 val;
+ enum kp_band kp_index;
+ unsigned long ref_freq;
+ const char *clk_name = clk_hw_get_name(&clk->hw);
+
+ /*
+ * reference frequency = parent frequency / PDIV
+ * If PDIV = 0, then it becomes a multiplier (x2)
+ */
+ if (vco->pdiv == 0)
+ ref_freq = parent_rate * 2;
+ else
+ ref_freq = parent_rate / vco->pdiv;
+
+ /* determine Ki and Kp index based on target VCO frequency */
+ if (rate >= VCO_LOW && rate < VCO_HIGH) {
+ ki = 4;
+ kp_index = KP_BAND_MID;
+ } else if (rate >= VCO_HIGH && rate < VCO_HIGH_HIGH) {
+ ki = 3;
+ kp_index = KP_BAND_HIGH;
+ } else if (rate >= VCO_HIGH_HIGH && rate < VCO_MAX) {
+ ki = 3;
+ kp_index = KP_BAND_HIGH_HIGH;
+ } else {
+ pr_err("%s: pll: %s has invalid rate: %lu\n", __func__,
+ clk_name, rate);
+ return -EINVAL;
+ }
+
+ kp = get_kp(ref_freq, kp_index);
+ if (kp < 0) {
+ pr_err("%s: pll: %s has invalid kp\n", __func__, clk_name);
+ return kp;
+ }
+
+ ret = __pll_enable(pll);
+ if (ret) {
+ pr_err("%s: pll: %s fails to enable\n", __func__, clk_name);
+ return ret;
+ }
+
+ if (pll_fractional_change_only(clk->pll, vco)) {
+ /* program fractional part of NDIV */
+ if (ctrl->flags & IPROC_CLK_PLL_HAS_NDIV_FRAC) {
+ val = readl(pll->control_base + ctrl->ndiv_frac.offset);
+ val &= ~(bit_mask(ctrl->ndiv_frac.width) <<
+ ctrl->ndiv_frac.shift);
+ val |= vco->ndiv_frac << ctrl->ndiv_frac.shift;
+ iproc_pll_write(pll, pll->control_base,
+ ctrl->ndiv_frac.offset, val);
+ return 0;
+ }
+ }
+
+ /* put PLL in reset */
+ __pll_put_in_reset(pll);
+
+ /* set PLL in user mode before modifying PLL controls */
+ if (ctrl->flags & IPROC_CLK_PLL_USER_MODE_ON) {
+ val = readl(pll->control_base + ctrl->macro_mode.offset);
+ val &= ~(bit_mask(ctrl->macro_mode.width) <<
+ ctrl->macro_mode.shift);
+ val |= PLL_USER_MODE << ctrl->macro_mode.shift;
+ iproc_pll_write(pll, pll->control_base,
+ ctrl->macro_mode.offset, val);
+ }
+
+ iproc_pll_write(pll, pll->control_base, ctrl->vco_ctrl.u_offset, 0);
+
+ val = readl(pll->control_base + ctrl->vco_ctrl.l_offset);
+
+ if (rate >= VCO_LOW && rate < VCO_MID)
+ val |= (1 << PLL_VCO_LOW_SHIFT);
+
+ if (rate < VCO_HIGH)
+ val &= ~(1 << PLL_VCO_HIGH_SHIFT);
+ else
+ val |= (1 << PLL_VCO_HIGH_SHIFT);
+
+ iproc_pll_write(pll, pll->control_base, ctrl->vco_ctrl.l_offset, val);
+
+ /* program integer part of NDIV */
+ val = readl(pll->control_base + ctrl->ndiv_int.offset);
+ val &= ~(bit_mask(ctrl->ndiv_int.width) << ctrl->ndiv_int.shift);
+ val |= vco->ndiv_int << ctrl->ndiv_int.shift;
+ iproc_pll_write(pll, pll->control_base, ctrl->ndiv_int.offset, val);
+
+ /* program fractional part of NDIV */
+ if (ctrl->flags & IPROC_CLK_PLL_HAS_NDIV_FRAC) {
+ val = readl(pll->control_base + ctrl->ndiv_frac.offset);
+ val &= ~(bit_mask(ctrl->ndiv_frac.width) <<
+ ctrl->ndiv_frac.shift);
+ val |= vco->ndiv_frac << ctrl->ndiv_frac.shift;
+ iproc_pll_write(pll, pll->control_base, ctrl->ndiv_frac.offset,
+ val);
+ }
+
+ /* program PDIV */
+ val = readl(pll->control_base + ctrl->pdiv.offset);
+ val &= ~(bit_mask(ctrl->pdiv.width) << ctrl->pdiv.shift);
+ val |= vco->pdiv << ctrl->pdiv.shift;
+ iproc_pll_write(pll, pll->control_base, ctrl->pdiv.offset, val);
+
+ __pll_bring_out_reset(pll, kp, ka, ki);
+
+ ret = pll_wait_for_lock(pll);
+ if (ret < 0) {
+ pr_err("%s: pll: %s failed to lock\n", __func__, clk_name);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int iproc_pll_enable(struct clk_hw *hw)
+{
+ struct iproc_clk *clk = to_iproc_clk(hw);
+ struct iproc_pll *pll = clk->pll;
+
+ return __pll_enable(pll);
+}
+
+static void iproc_pll_disable(struct clk_hw *hw)
+{
+ struct iproc_clk *clk = to_iproc_clk(hw);
+ struct iproc_pll *pll = clk->pll;
+ const struct iproc_pll_ctrl *ctrl = pll->ctrl;
+
+ if (ctrl->flags & IPROC_CLK_AON)
+ return;
+
+ __pll_disable(pll);
+}
+
+static unsigned long iproc_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct iproc_clk *clk = to_iproc_clk(hw);
+ struct iproc_pll *pll = clk->pll;
+ const struct iproc_pll_ctrl *ctrl = pll->ctrl;
+ u32 val;
+ u64 ndiv, ndiv_int, ndiv_frac;
+ unsigned int pdiv;
+ unsigned long rate;
+
+ if (parent_rate == 0)
+ return 0;
+
+ /* PLL needs to be locked */
+ val = readl(pll->status_base + ctrl->status.offset);
+ if ((val & (1 << ctrl->status.shift)) == 0)
+ return 0;
+
+ /*
+ * PLL output frequency =
+ *
+ * ((ndiv_int + ndiv_frac / 2^20) * (parent clock rate / pdiv)
+ */
+ val = readl(pll->control_base + ctrl->ndiv_int.offset);
+ ndiv_int = (val >> ctrl->ndiv_int.shift) &
+ bit_mask(ctrl->ndiv_int.width);
+ ndiv = ndiv_int << 20;
+
+ if (ctrl->flags & IPROC_CLK_PLL_HAS_NDIV_FRAC) {
+ val = readl(pll->control_base + ctrl->ndiv_frac.offset);
+ ndiv_frac = (val >> ctrl->ndiv_frac.shift) &
+ bit_mask(ctrl->ndiv_frac.width);
+ ndiv += ndiv_frac;
+ }
+
+ val = readl(pll->control_base + ctrl->pdiv.offset);
+ pdiv = (val >> ctrl->pdiv.shift) & bit_mask(ctrl->pdiv.width);
+
+ rate = (ndiv * parent_rate) >> 20;
+
+ if (pdiv == 0)
+ rate *= 2;
+ else
+ rate /= pdiv;
+
+ return rate;
+}
+
+static int iproc_pll_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ unsigned int i;
+ struct iproc_clk *clk = to_iproc_clk(hw);
+ struct iproc_pll *pll = clk->pll;
+ const struct iproc_pll_ctrl *ctrl = pll->ctrl;
+ unsigned long diff, best_diff;
+ unsigned int best_idx = 0;
+ int ret;
+
+ if (req->rate == 0 || req->best_parent_rate == 0)
+ return -EINVAL;
+
+ if (ctrl->flags & IPROC_CLK_PLL_CALC_PARAM) {
+ struct iproc_pll_vco_param vco_param;
+
+ ret = pll_calc_param(req->rate, req->best_parent_rate,
+ &vco_param);
+ if (ret)
+ return ret;
+
+ req->rate = vco_param.rate;
+ return 0;
+ }
+
+ if (!pll->vco_param)
+ return -EINVAL;
+
+ best_diff = ULONG_MAX;
+ for (i = 0; i < pll->num_vco_entries; i++) {
+ diff = abs(req->rate - pll->vco_param[i].rate);
+ if (diff <= best_diff) {
+ best_diff = diff;
+ best_idx = i;
+ }
+ /* break now if perfect match */
+ if (diff == 0)
+ break;
+ }
+
+ req->rate = pll->vco_param[best_idx].rate;
+
+ return 0;
+}
+
+static int iproc_pll_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct iproc_clk *clk = to_iproc_clk(hw);
+ struct iproc_pll *pll = clk->pll;
+ const struct iproc_pll_ctrl *ctrl = pll->ctrl;
+ struct iproc_pll_vco_param vco_param;
+ int rate_index, ret;
+
+ if (ctrl->flags & IPROC_CLK_PLL_CALC_PARAM) {
+ ret = pll_calc_param(rate, parent_rate, &vco_param);
+ if (ret)
+ return ret;
+ } else {
+ rate_index = pll_get_rate_index(pll, rate);
+ if (rate_index < 0)
+ return rate_index;
+
+ vco_param = pll->vco_param[rate_index];
+ }
+
+ ret = pll_set_rate(clk, &vco_param, parent_rate);
+ return ret;
+}
+
+static const struct clk_ops iproc_pll_ops = {
+ .enable = iproc_pll_enable,
+ .disable = iproc_pll_disable,
+ .recalc_rate = iproc_pll_recalc_rate,
+ .determine_rate = iproc_pll_determine_rate,
+ .set_rate = iproc_pll_set_rate,
+};
+
+static int iproc_clk_enable(struct clk_hw *hw)
+{
+ struct iproc_clk *clk = to_iproc_clk(hw);
+ const struct iproc_clk_ctrl *ctrl = clk->ctrl;
+ struct iproc_pll *pll = clk->pll;
+ u32 val;
+
+ /* channel enable is active low */
+ val = readl(pll->control_base + ctrl->enable.offset);
+ val &= ~(1 << ctrl->enable.enable_shift);
+ iproc_pll_write(pll, pll->control_base, ctrl->enable.offset, val);
+
+ /* also make sure channel is not held */
+ val = readl(pll->control_base + ctrl->enable.offset);
+ val &= ~(1 << ctrl->enable.hold_shift);
+ iproc_pll_write(pll, pll->control_base, ctrl->enable.offset, val);
+
+ return 0;
+}
+
+static void iproc_clk_disable(struct clk_hw *hw)
+{
+ struct iproc_clk *clk = to_iproc_clk(hw);
+ const struct iproc_clk_ctrl *ctrl = clk->ctrl;
+ struct iproc_pll *pll = clk->pll;
+ u32 val;
+
+ if (ctrl->flags & IPROC_CLK_AON)
+ return;
+
+ val = readl(pll->control_base + ctrl->enable.offset);
+ val |= 1 << ctrl->enable.enable_shift;
+ iproc_pll_write(pll, pll->control_base, ctrl->enable.offset, val);
+}
+
+static unsigned long iproc_clk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct iproc_clk *clk = to_iproc_clk(hw);
+ const struct iproc_clk_ctrl *ctrl = clk->ctrl;
+ struct iproc_pll *pll = clk->pll;
+ u32 val;
+ unsigned int mdiv;
+ unsigned long rate;
+
+ if (parent_rate == 0)
+ return 0;
+
+ val = readl(pll->control_base + ctrl->mdiv.offset);
+ mdiv = (val >> ctrl->mdiv.shift) & bit_mask(ctrl->mdiv.width);
+ if (mdiv == 0)
+ mdiv = 256;
+
+ if (ctrl->flags & IPROC_CLK_MCLK_DIV_BY_2)
+ rate = parent_rate / (mdiv * 2);
+ else
+ rate = parent_rate / mdiv;
+
+ return rate;
+}
+
+static int iproc_clk_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ unsigned int bestdiv;
+
+ if (req->rate == 0)
+ return -EINVAL;
+ if (req->rate == req->best_parent_rate)
+ return 0;
+
+ bestdiv = DIV_ROUND_CLOSEST(req->best_parent_rate, req->rate);
+ if (bestdiv < 2)
+ req->rate = req->best_parent_rate;
+
+ if (bestdiv > 256)
+ bestdiv = 256;
+
+ req->rate = req->best_parent_rate / bestdiv;
+
+ return 0;
+}
+
+static int iproc_clk_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct iproc_clk *clk = to_iproc_clk(hw);
+ const struct iproc_clk_ctrl *ctrl = clk->ctrl;
+ struct iproc_pll *pll = clk->pll;
+ u32 val;
+ unsigned int div;
+
+ if (rate == 0 || parent_rate == 0)
+ return -EINVAL;
+
+ div = DIV_ROUND_CLOSEST(parent_rate, rate);
+ if (ctrl->flags & IPROC_CLK_MCLK_DIV_BY_2)
+ div /= 2;
+
+ if (div > 256)
+ return -EINVAL;
+
+ val = readl(pll->control_base + ctrl->mdiv.offset);
+ if (div == 256) {
+ val &= ~(bit_mask(ctrl->mdiv.width) << ctrl->mdiv.shift);
+ } else {
+ val &= ~(bit_mask(ctrl->mdiv.width) << ctrl->mdiv.shift);
+ val |= div << ctrl->mdiv.shift;
+ }
+ iproc_pll_write(pll, pll->control_base, ctrl->mdiv.offset, val);
+
+ return 0;
+}
+
+static const struct clk_ops iproc_clk_ops = {
+ .enable = iproc_clk_enable,
+ .disable = iproc_clk_disable,
+ .recalc_rate = iproc_clk_recalc_rate,
+ .determine_rate = iproc_clk_determine_rate,
+ .set_rate = iproc_clk_set_rate,
+};
+
+/*
+ * Some PLLs require the PLL SW override bit to be set before changes can be
+ * applied to the PLL
+ */
+static void iproc_pll_sw_cfg(struct iproc_pll *pll)
+{
+ const struct iproc_pll_ctrl *ctrl = pll->ctrl;
+
+ if (ctrl->flags & IPROC_CLK_PLL_NEEDS_SW_CFG) {
+ u32 val;
+
+ val = readl(pll->control_base + ctrl->sw_ctrl.offset);
+ val |= BIT(ctrl->sw_ctrl.shift);
+ iproc_pll_write(pll, pll->control_base, ctrl->sw_ctrl.offset,
+ val);
+ }
+}
+
+void iproc_pll_clk_setup(struct device_node *node,
+ const struct iproc_pll_ctrl *pll_ctrl,
+ const struct iproc_pll_vco_param *vco,
+ unsigned int num_vco_entries,
+ const struct iproc_clk_ctrl *clk_ctrl,
+ unsigned int num_clks)
+{
+ int i, ret;
+ struct iproc_pll *pll;
+ struct iproc_clk *iclk;
+ struct clk_init_data init;
+ const char *parent_name;
+ struct iproc_clk *iclk_array;
+ struct clk_hw_onecell_data *clk_data;
+ const char *clk_name;
+
+ if (WARN_ON(!pll_ctrl) || WARN_ON(!clk_ctrl))
+ return;
+
+ pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+ if (WARN_ON(!pll))
+ return;
+
+ clk_data = kzalloc(struct_size(clk_data, hws, num_clks), GFP_KERNEL);
+ if (WARN_ON(!clk_data))
+ goto err_clk_data;
+ clk_data->num = num_clks;
+
+ iclk_array = kcalloc(num_clks, sizeof(struct iproc_clk), GFP_KERNEL);
+ if (WARN_ON(!iclk_array))
+ goto err_clks;
+
+ pll->control_base = of_iomap(node, 0);
+ if (WARN_ON(!pll->control_base))
+ goto err_pll_iomap;
+
+ /* Some SoCs do not require the pwr_base, thus failing is not fatal */
+ pll->pwr_base = of_iomap(node, 1);
+
+ /* some PLLs require gating control at the top ASIU level */
+ if (pll_ctrl->flags & IPROC_CLK_PLL_ASIU) {
+ pll->asiu_base = of_iomap(node, 2);
+ if (WARN_ON(!pll->asiu_base))
+ goto err_asiu_iomap;
+ }
+
+ if (pll_ctrl->flags & IPROC_CLK_PLL_SPLIT_STAT_CTRL) {
+ /* Some SoCs have a split status/control. If this does not
+ * exist, assume they are unified.
+ */
+ pll->status_base = of_iomap(node, 2);
+ if (!pll->status_base)
+ goto err_status_iomap;
+ } else
+ pll->status_base = pll->control_base;
+
+ /* initialize and register the PLL itself */
+ pll->ctrl = pll_ctrl;
+
+ iclk = &iclk_array[0];
+ iclk->pll = pll;
+
+ ret = of_property_read_string_index(node, "clock-output-names",
+ 0, &clk_name);
+ if (WARN_ON(ret))
+ goto err_pll_register;
+
+ init.name = clk_name;
+ init.ops = &iproc_pll_ops;
+ init.flags = 0;
+ parent_name = of_clk_get_parent_name(node, 0);
+ init.parent_names = (parent_name ? &parent_name : NULL);
+ init.num_parents = (parent_name ? 1 : 0);
+ iclk->hw.init = &init;
+
+ if (vco) {
+ pll->num_vco_entries = num_vco_entries;
+ pll->vco_param = vco;
+ }
+
+ iproc_pll_sw_cfg(pll);
+
+ ret = clk_hw_register(NULL, &iclk->hw);
+ if (WARN_ON(ret))
+ goto err_pll_register;
+
+ clk_data->hws[0] = &iclk->hw;
+ parent_name = clk_name;
+
+ /* now initialize and register all leaf clocks */
+ for (i = 1; i < num_clks; i++) {
+ memset(&init, 0, sizeof(init));
+
+ ret = of_property_read_string_index(node, "clock-output-names",
+ i, &clk_name);
+ if (WARN_ON(ret))
+ goto err_clk_register;
+
+ iclk = &iclk_array[i];
+ iclk->pll = pll;
+ iclk->ctrl = &clk_ctrl[i];
+
+ init.name = clk_name;
+ init.ops = &iproc_clk_ops;
+ init.flags = 0;
+ init.parent_names = (parent_name ? &parent_name : NULL);
+ init.num_parents = (parent_name ? 1 : 0);
+ iclk->hw.init = &init;
+
+ ret = clk_hw_register(NULL, &iclk->hw);
+ if (WARN_ON(ret))
+ goto err_clk_register;
+
+ clk_data->hws[i] = &iclk->hw;
+ }
+
+ ret = of_clk_add_hw_provider(node, of_clk_hw_onecell_get, clk_data);
+ if (WARN_ON(ret))
+ goto err_clk_register;
+
+ return;
+
+err_clk_register:
+ while (--i >= 0)
+ clk_hw_unregister(clk_data->hws[i]);
+
+err_pll_register:
+ if (pll->status_base != pll->control_base)
+ iounmap(pll->status_base);
+
+err_status_iomap:
+ if (pll->asiu_base)
+ iounmap(pll->asiu_base);
+
+err_asiu_iomap:
+ if (pll->pwr_base)
+ iounmap(pll->pwr_base);
+
+ iounmap(pll->control_base);
+
+err_pll_iomap:
+ kfree(iclk_array);
+
+err_clks:
+ kfree(clk_data);
+
+err_clk_data:
+ kfree(pll);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-06 06:40:52 +0000