![Anson Huang](/assets/img/avatar_default.png)
No need to initialize 'ret' in many functions, as it will get the return value from function call, so remove the initializtion of 'ret'. Signed-off-by: Anson Huang <Anson.Huang@nxp.com> Reviewed-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
550 lines
13 KiB
C
550 lines
13 KiB
C
// SPDX-License-Identifier: (GPL-2.0 OR MIT)
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/*
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* Copyright 2018 NXP.
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*
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* This driver supports the SCCG plls found in the imx8m SOCs
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*
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* Documentation for this SCCG pll can be found at:
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* https://www.nxp.com/docs/en/reference-manual/IMX8MDQLQRM.pdf#page=834
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*/
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#include <linux/clk-provider.h>
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#include <linux/err.h>
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#include <linux/io.h>
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#include <linux/iopoll.h>
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#include <linux/slab.h>
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#include <linux/bitfield.h>
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#include "clk.h"
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/* PLL CFGs */
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#define PLL_CFG0 0x0
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#define PLL_CFG1 0x4
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#define PLL_CFG2 0x8
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#define PLL_DIVF1_MASK GENMASK(18, 13)
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#define PLL_DIVF2_MASK GENMASK(12, 7)
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#define PLL_DIVR1_MASK GENMASK(27, 25)
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#define PLL_DIVR2_MASK GENMASK(24, 19)
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#define PLL_DIVQ_MASK GENMASK(6, 1)
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#define PLL_REF_MASK GENMASK(2, 0)
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#define PLL_LOCK_MASK BIT(31)
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#define PLL_PD_MASK BIT(7)
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/* These are the specification limits for the SSCG PLL */
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#define PLL_REF_MIN_FREQ 25000000UL
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#define PLL_REF_MAX_FREQ 235000000UL
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#define PLL_STAGE1_MIN_FREQ 1600000000UL
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#define PLL_STAGE1_MAX_FREQ 2400000000UL
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#define PLL_STAGE1_REF_MIN_FREQ 25000000UL
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#define PLL_STAGE1_REF_MAX_FREQ 54000000UL
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#define PLL_STAGE2_MIN_FREQ 1200000000UL
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#define PLL_STAGE2_MAX_FREQ 2400000000UL
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#define PLL_STAGE2_REF_MIN_FREQ 54000000UL
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#define PLL_STAGE2_REF_MAX_FREQ 75000000UL
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#define PLL_OUT_MIN_FREQ 20000000UL
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#define PLL_OUT_MAX_FREQ 1200000000UL
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#define PLL_DIVR1_MAX 7
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#define PLL_DIVR2_MAX 63
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#define PLL_DIVF1_MAX 63
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#define PLL_DIVF2_MAX 63
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#define PLL_DIVQ_MAX 63
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#define PLL_BYPASS_NONE 0x0
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#define PLL_BYPASS1 0x2
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#define PLL_BYPASS2 0x1
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#define SSCG_PLL_BYPASS1_MASK BIT(5)
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#define SSCG_PLL_BYPASS2_MASK BIT(4)
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#define SSCG_PLL_BYPASS_MASK GENMASK(5, 4)
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#define PLL_SCCG_LOCK_TIMEOUT 70
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struct clk_sscg_pll_setup {
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int divr1, divf1;
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int divr2, divf2;
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int divq;
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int bypass;
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uint64_t vco1;
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uint64_t vco2;
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uint64_t fout;
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uint64_t ref;
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uint64_t ref_div1;
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uint64_t ref_div2;
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uint64_t fout_request;
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int fout_error;
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};
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struct clk_sscg_pll {
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struct clk_hw hw;
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const struct clk_ops ops;
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void __iomem *base;
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struct clk_sscg_pll_setup setup;
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u8 parent;
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u8 bypass1;
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u8 bypass2;
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};
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#define to_clk_sscg_pll(_hw) container_of(_hw, struct clk_sscg_pll, hw)
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static int clk_sscg_pll_wait_lock(struct clk_sscg_pll *pll)
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{
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u32 val;
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val = readl_relaxed(pll->base + PLL_CFG0);
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/* don't wait for lock if all plls are bypassed */
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if (!(val & SSCG_PLL_BYPASS2_MASK))
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return readl_poll_timeout(pll->base, val, val & PLL_LOCK_MASK,
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0, PLL_SCCG_LOCK_TIMEOUT);
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return 0;
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}
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static int clk_sscg_pll2_check_match(struct clk_sscg_pll_setup *setup,
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struct clk_sscg_pll_setup *temp_setup)
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{
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int new_diff = temp_setup->fout - temp_setup->fout_request;
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int diff = temp_setup->fout_error;
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if (abs(diff) > abs(new_diff)) {
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temp_setup->fout_error = new_diff;
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memcpy(setup, temp_setup, sizeof(struct clk_sscg_pll_setup));
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if (temp_setup->fout_request == temp_setup->fout)
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return 0;
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}
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return -1;
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}
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static int clk_sscg_divq_lookup(struct clk_sscg_pll_setup *setup,
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struct clk_sscg_pll_setup *temp_setup)
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{
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int ret = -EINVAL;
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for (temp_setup->divq = 0; temp_setup->divq <= PLL_DIVQ_MAX;
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temp_setup->divq++) {
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temp_setup->vco2 = temp_setup->vco1;
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do_div(temp_setup->vco2, temp_setup->divr2 + 1);
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temp_setup->vco2 *= 2;
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temp_setup->vco2 *= temp_setup->divf2 + 1;
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if (temp_setup->vco2 >= PLL_STAGE2_MIN_FREQ &&
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temp_setup->vco2 <= PLL_STAGE2_MAX_FREQ) {
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temp_setup->fout = temp_setup->vco2;
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do_div(temp_setup->fout, 2 * (temp_setup->divq + 1));
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ret = clk_sscg_pll2_check_match(setup, temp_setup);
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if (!ret) {
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temp_setup->bypass = PLL_BYPASS1;
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return ret;
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}
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}
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}
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return ret;
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}
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static int clk_sscg_divf2_lookup(struct clk_sscg_pll_setup *setup,
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struct clk_sscg_pll_setup *temp_setup)
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{
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int ret = -EINVAL;
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for (temp_setup->divf2 = 0; temp_setup->divf2 <= PLL_DIVF2_MAX;
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temp_setup->divf2++) {
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ret = clk_sscg_divq_lookup(setup, temp_setup);
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if (!ret)
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return ret;
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}
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return ret;
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}
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static int clk_sscg_divr2_lookup(struct clk_sscg_pll_setup *setup,
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struct clk_sscg_pll_setup *temp_setup)
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{
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int ret = -EINVAL;
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for (temp_setup->divr2 = 0; temp_setup->divr2 <= PLL_DIVR2_MAX;
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temp_setup->divr2++) {
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temp_setup->ref_div2 = temp_setup->vco1;
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do_div(temp_setup->ref_div2, temp_setup->divr2 + 1);
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if (temp_setup->ref_div2 >= PLL_STAGE2_REF_MIN_FREQ &&
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temp_setup->ref_div2 <= PLL_STAGE2_REF_MAX_FREQ) {
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ret = clk_sscg_divf2_lookup(setup, temp_setup);
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if (!ret)
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return ret;
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}
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}
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return ret;
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}
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static int clk_sscg_pll2_find_setup(struct clk_sscg_pll_setup *setup,
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struct clk_sscg_pll_setup *temp_setup,
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uint64_t ref)
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{
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int ret;
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if (ref < PLL_STAGE1_MIN_FREQ || ref > PLL_STAGE1_MAX_FREQ)
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return -EINVAL;
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temp_setup->vco1 = ref;
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ret = clk_sscg_divr2_lookup(setup, temp_setup);
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return ret;
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}
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static int clk_sscg_divf1_lookup(struct clk_sscg_pll_setup *setup,
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struct clk_sscg_pll_setup *temp_setup)
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{
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int ret = -EINVAL;
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for (temp_setup->divf1 = 0; temp_setup->divf1 <= PLL_DIVF1_MAX;
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temp_setup->divf1++) {
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uint64_t vco1 = temp_setup->ref;
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do_div(vco1, temp_setup->divr1 + 1);
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vco1 *= 2;
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vco1 *= temp_setup->divf1 + 1;
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ret = clk_sscg_pll2_find_setup(setup, temp_setup, vco1);
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if (!ret) {
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temp_setup->bypass = PLL_BYPASS_NONE;
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return ret;
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}
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}
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return ret;
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}
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static int clk_sscg_divr1_lookup(struct clk_sscg_pll_setup *setup,
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struct clk_sscg_pll_setup *temp_setup)
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{
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int ret = -EINVAL;
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for (temp_setup->divr1 = 0; temp_setup->divr1 <= PLL_DIVR1_MAX;
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temp_setup->divr1++) {
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temp_setup->ref_div1 = temp_setup->ref;
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do_div(temp_setup->ref_div1, temp_setup->divr1 + 1);
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if (temp_setup->ref_div1 >= PLL_STAGE1_REF_MIN_FREQ &&
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temp_setup->ref_div1 <= PLL_STAGE1_REF_MAX_FREQ) {
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ret = clk_sscg_divf1_lookup(setup, temp_setup);
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if (!ret)
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return ret;
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}
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}
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return ret;
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}
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static int clk_sscg_pll1_find_setup(struct clk_sscg_pll_setup *setup,
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struct clk_sscg_pll_setup *temp_setup,
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uint64_t ref)
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{
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int ret;
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if (ref < PLL_REF_MIN_FREQ || ref > PLL_REF_MAX_FREQ)
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return -EINVAL;
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temp_setup->ref = ref;
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ret = clk_sscg_divr1_lookup(setup, temp_setup);
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return ret;
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}
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static int clk_sscg_pll_find_setup(struct clk_sscg_pll_setup *setup,
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uint64_t prate,
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uint64_t rate, int try_bypass)
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{
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struct clk_sscg_pll_setup temp_setup;
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int ret = -EINVAL;
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memset(&temp_setup, 0, sizeof(struct clk_sscg_pll_setup));
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memset(setup, 0, sizeof(struct clk_sscg_pll_setup));
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temp_setup.fout_error = PLL_OUT_MAX_FREQ;
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temp_setup.fout_request = rate;
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switch (try_bypass) {
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case PLL_BYPASS2:
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if (prate == rate) {
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setup->bypass = PLL_BYPASS2;
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setup->fout = rate;
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ret = 0;
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}
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break;
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case PLL_BYPASS1:
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ret = clk_sscg_pll2_find_setup(setup, &temp_setup, prate);
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break;
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case PLL_BYPASS_NONE:
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ret = clk_sscg_pll1_find_setup(setup, &temp_setup, prate);
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break;
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}
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return ret;
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}
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static int clk_sscg_pll_is_prepared(struct clk_hw *hw)
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{
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struct clk_sscg_pll *pll = to_clk_sscg_pll(hw);
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u32 val = readl_relaxed(pll->base + PLL_CFG0);
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return (val & PLL_PD_MASK) ? 0 : 1;
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}
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static int clk_sscg_pll_prepare(struct clk_hw *hw)
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{
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struct clk_sscg_pll *pll = to_clk_sscg_pll(hw);
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u32 val;
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val = readl_relaxed(pll->base + PLL_CFG0);
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val &= ~PLL_PD_MASK;
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writel_relaxed(val, pll->base + PLL_CFG0);
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return clk_sscg_pll_wait_lock(pll);
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}
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static void clk_sscg_pll_unprepare(struct clk_hw *hw)
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{
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struct clk_sscg_pll *pll = to_clk_sscg_pll(hw);
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u32 val;
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val = readl_relaxed(pll->base + PLL_CFG0);
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val |= PLL_PD_MASK;
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writel_relaxed(val, pll->base + PLL_CFG0);
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}
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static unsigned long clk_sscg_pll_recalc_rate(struct clk_hw *hw,
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unsigned long parent_rate)
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{
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struct clk_sscg_pll *pll = to_clk_sscg_pll(hw);
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u32 val, divr1, divf1, divr2, divf2, divq;
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u64 temp64;
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val = readl_relaxed(pll->base + PLL_CFG2);
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divr1 = FIELD_GET(PLL_DIVR1_MASK, val);
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divr2 = FIELD_GET(PLL_DIVR2_MASK, val);
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divf1 = FIELD_GET(PLL_DIVF1_MASK, val);
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divf2 = FIELD_GET(PLL_DIVF2_MASK, val);
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divq = FIELD_GET(PLL_DIVQ_MASK, val);
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temp64 = parent_rate;
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val = readl(pll->base + PLL_CFG0);
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if (val & SSCG_PLL_BYPASS2_MASK) {
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temp64 = parent_rate;
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} else if (val & SSCG_PLL_BYPASS1_MASK) {
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temp64 *= divf2;
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do_div(temp64, (divr2 + 1) * (divq + 1));
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} else {
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temp64 *= 2;
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temp64 *= (divf1 + 1) * (divf2 + 1);
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do_div(temp64, (divr1 + 1) * (divr2 + 1) * (divq + 1));
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}
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return temp64;
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}
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static int clk_sscg_pll_set_rate(struct clk_hw *hw, unsigned long rate,
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unsigned long parent_rate)
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{
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struct clk_sscg_pll *pll = to_clk_sscg_pll(hw);
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struct clk_sscg_pll_setup *setup = &pll->setup;
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u32 val;
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/* set bypass here too since the parent might be the same */
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val = readl(pll->base + PLL_CFG0);
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val &= ~SSCG_PLL_BYPASS_MASK;
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val |= FIELD_PREP(SSCG_PLL_BYPASS_MASK, setup->bypass);
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writel(val, pll->base + PLL_CFG0);
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val = readl_relaxed(pll->base + PLL_CFG2);
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val &= ~(PLL_DIVF1_MASK | PLL_DIVF2_MASK);
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val &= ~(PLL_DIVR1_MASK | PLL_DIVR2_MASK | PLL_DIVQ_MASK);
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val |= FIELD_PREP(PLL_DIVF1_MASK, setup->divf1);
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val |= FIELD_PREP(PLL_DIVF2_MASK, setup->divf2);
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val |= FIELD_PREP(PLL_DIVR1_MASK, setup->divr1);
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val |= FIELD_PREP(PLL_DIVR2_MASK, setup->divr2);
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val |= FIELD_PREP(PLL_DIVQ_MASK, setup->divq);
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writel_relaxed(val, pll->base + PLL_CFG2);
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return clk_sscg_pll_wait_lock(pll);
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}
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static u8 clk_sscg_pll_get_parent(struct clk_hw *hw)
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{
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struct clk_sscg_pll *pll = to_clk_sscg_pll(hw);
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u32 val;
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u8 ret = pll->parent;
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val = readl(pll->base + PLL_CFG0);
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if (val & SSCG_PLL_BYPASS2_MASK)
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ret = pll->bypass2;
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else if (val & SSCG_PLL_BYPASS1_MASK)
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ret = pll->bypass1;
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return ret;
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}
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static int clk_sscg_pll_set_parent(struct clk_hw *hw, u8 index)
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{
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struct clk_sscg_pll *pll = to_clk_sscg_pll(hw);
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u32 val;
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val = readl(pll->base + PLL_CFG0);
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val &= ~SSCG_PLL_BYPASS_MASK;
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val |= FIELD_PREP(SSCG_PLL_BYPASS_MASK, pll->setup.bypass);
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writel(val, pll->base + PLL_CFG0);
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return clk_sscg_pll_wait_lock(pll);
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}
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static int __clk_sscg_pll_determine_rate(struct clk_hw *hw,
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struct clk_rate_request *req,
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uint64_t min,
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uint64_t max,
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uint64_t rate,
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int bypass)
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{
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struct clk_sscg_pll *pll = to_clk_sscg_pll(hw);
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struct clk_sscg_pll_setup *setup = &pll->setup;
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struct clk_hw *parent_hw = NULL;
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int bypass_parent_index;
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int ret;
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req->max_rate = max;
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req->min_rate = min;
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switch (bypass) {
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case PLL_BYPASS2:
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bypass_parent_index = pll->bypass2;
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break;
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case PLL_BYPASS1:
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bypass_parent_index = pll->bypass1;
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break;
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default:
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bypass_parent_index = pll->parent;
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break;
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}
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parent_hw = clk_hw_get_parent_by_index(hw, bypass_parent_index);
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ret = __clk_determine_rate(parent_hw, req);
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if (!ret) {
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ret = clk_sscg_pll_find_setup(setup, req->rate,
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rate, bypass);
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}
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req->best_parent_hw = parent_hw;
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req->best_parent_rate = req->rate;
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req->rate = setup->fout;
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return ret;
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}
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static int clk_sscg_pll_determine_rate(struct clk_hw *hw,
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struct clk_rate_request *req)
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{
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struct clk_sscg_pll *pll = to_clk_sscg_pll(hw);
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struct clk_sscg_pll_setup *setup = &pll->setup;
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uint64_t rate = req->rate;
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uint64_t min = req->min_rate;
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uint64_t max = req->max_rate;
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int ret;
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if (rate < PLL_OUT_MIN_FREQ || rate > PLL_OUT_MAX_FREQ)
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return -EINVAL;
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ret = __clk_sscg_pll_determine_rate(hw, req, req->rate, req->rate,
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rate, PLL_BYPASS2);
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if (!ret)
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return ret;
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ret = __clk_sscg_pll_determine_rate(hw, req, PLL_STAGE1_REF_MIN_FREQ,
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PLL_STAGE1_REF_MAX_FREQ, rate,
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PLL_BYPASS1);
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if (!ret)
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return ret;
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ret = __clk_sscg_pll_determine_rate(hw, req, PLL_REF_MIN_FREQ,
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PLL_REF_MAX_FREQ, rate,
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PLL_BYPASS_NONE);
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if (!ret)
|
|
return ret;
|
|
|
|
if (setup->fout >= min && setup->fout <= max)
|
|
ret = 0;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static const struct clk_ops clk_sscg_pll_ops = {
|
|
.prepare = clk_sscg_pll_prepare,
|
|
.unprepare = clk_sscg_pll_unprepare,
|
|
.is_prepared = clk_sscg_pll_is_prepared,
|
|
.recalc_rate = clk_sscg_pll_recalc_rate,
|
|
.set_rate = clk_sscg_pll_set_rate,
|
|
.set_parent = clk_sscg_pll_set_parent,
|
|
.get_parent = clk_sscg_pll_get_parent,
|
|
.determine_rate = clk_sscg_pll_determine_rate,
|
|
};
|
|
|
|
struct clk_hw *imx_clk_hw_sscg_pll(const char *name,
|
|
const char * const *parent_names,
|
|
u8 num_parents,
|
|
u8 parent, u8 bypass1, u8 bypass2,
|
|
void __iomem *base,
|
|
unsigned long flags)
|
|
{
|
|
struct clk_sscg_pll *pll;
|
|
struct clk_init_data init;
|
|
struct clk_hw *hw;
|
|
int ret;
|
|
|
|
pll = kzalloc(sizeof(*pll), GFP_KERNEL);
|
|
if (!pll)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
pll->parent = parent;
|
|
pll->bypass1 = bypass1;
|
|
pll->bypass2 = bypass2;
|
|
|
|
pll->base = base;
|
|
init.name = name;
|
|
init.ops = &clk_sscg_pll_ops;
|
|
|
|
init.flags = flags;
|
|
init.parent_names = parent_names;
|
|
init.num_parents = num_parents;
|
|
|
|
pll->base = base;
|
|
pll->hw.init = &init;
|
|
|
|
hw = &pll->hw;
|
|
|
|
ret = clk_hw_register(NULL, hw);
|
|
if (ret) {
|
|
kfree(pll);
|
|
return ERR_PTR(ret);
|
|
}
|
|
|
|
return hw;
|
|
}
|