diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/clk/clk-versaclock7.c | 1309 |
1 files changed, 1309 insertions, 0 deletions
diff --git a/drivers/clk/clk-versaclock7.c b/drivers/clk/clk-versaclock7.c new file mode 100644 index 000000000..0ae191f50 --- /dev/null +++ b/drivers/clk/clk-versaclock7.c @@ -0,0 +1,1309 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Common clock framework driver for the Versaclock7 family of timing devices. + * + * Copyright (c) 2022 Renesas Electronics Corporation + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/i2c.h> +#include <linux/math64.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/regmap.h> +#include <linux/swab.h> + +/* + * 16-bit register address: the lower 8 bits of the register address come + * from the offset addr byte and the upper 8 bits come from the page register. + */ +#define VC7_PAGE_ADDR 0xFD +#define VC7_PAGE_WINDOW 256 +#define VC7_MAX_REG 0x364 + +/* Maximum number of banks supported by VC7 */ +#define VC7_NUM_BANKS 7 + +/* Maximum number of FODs supported by VC7 */ +#define VC7_NUM_FOD 3 + +/* Maximum number of IODs supported by VC7 */ +#define VC7_NUM_IOD 4 + +/* Maximum number of outputs supported by VC7 */ +#define VC7_NUM_OUT 12 + +/* VCO valid range is 9.5 GHz to 10.7 GHz */ +#define VC7_APLL_VCO_MIN 9500000000UL +#define VC7_APLL_VCO_MAX 10700000000UL + +/* APLL denominator is fixed at 2^27 */ +#define VC7_APLL_DENOMINATOR_BITS 27 + +/* FOD 1st stage denominator is fixed 2^34 */ +#define VC7_FOD_DENOMINATOR_BITS 34 + +/* IOD can operate between 1kHz and 650MHz */ +#define VC7_IOD_RATE_MIN 1000UL +#define VC7_IOD_RATE_MAX 650000000UL +#define VC7_IOD_MIN_DIVISOR 14 +#define VC7_IOD_MAX_DIVISOR 0x1ffffff /* 25-bit */ + +#define VC7_FOD_RATE_MIN 1000UL +#define VC7_FOD_RATE_MAX 650000000UL +#define VC7_FOD_1ST_STAGE_RATE_MIN 33000000UL /* 33 MHz */ +#define VC7_FOD_1ST_STAGE_RATE_MAX 650000000UL /* 650 MHz */ +#define VC7_FOD_1ST_INT_MAX 324 +#define VC7_FOD_2ND_INT_MIN 2 +#define VC7_FOD_2ND_INT_MAX 0x1ffff /* 17-bit */ + +/* VC7 Registers */ + +#define VC7_REG_XO_CNFG 0x2C +#define VC7_REG_XO_CNFG_COUNT 4 +#define VC7_REG_XO_IB_H_DIV_SHIFT 24 +#define VC7_REG_XO_IB_H_DIV_MASK GENMASK(28, VC7_REG_XO_IB_H_DIV_SHIFT) + +#define VC7_REG_APLL_FB_DIV_FRAC 0x120 +#define VC7_REG_APLL_FB_DIV_FRAC_COUNT 4 +#define VC7_REG_APLL_FB_DIV_FRAC_MASK GENMASK(26, 0) + +#define VC7_REG_APLL_FB_DIV_INT 0x124 +#define VC7_REG_APLL_FB_DIV_INT_COUNT 2 +#define VC7_REG_APLL_FB_DIV_INT_MASK GENMASK(9, 0) + +#define VC7_REG_APLL_CNFG 0x127 +#define VC7_REG_APLL_EN_DOUBLER BIT(0) + +#define VC7_REG_OUT_BANK_CNFG(idx) (0x280 + (0x4 * (idx))) +#define VC7_REG_OUTPUT_BANK_SRC_MASK GENMASK(2, 0) + +#define VC7_REG_FOD_INT_CNFG(idx) (0x1E0 + (0x10 * (idx))) +#define VC7_REG_FOD_INT_CNFG_COUNT 8 +#define VC7_REG_FOD_1ST_INT_MASK GENMASK(8, 0) +#define VC7_REG_FOD_2ND_INT_SHIFT 9 +#define VC7_REG_FOD_2ND_INT_MASK GENMASK(25, VC7_REG_FOD_2ND_INT_SHIFT) +#define VC7_REG_FOD_FRAC_SHIFT 26 +#define VC7_REG_FOD_FRAC_MASK GENMASK_ULL(59, VC7_REG_FOD_FRAC_SHIFT) + +#define VC7_REG_IOD_INT_CNFG(idx) (0x1C0 + (0x8 * (idx))) +#define VC7_REG_IOD_INT_CNFG_COUNT 4 +#define VC7_REG_IOD_INT_MASK GENMASK(24, 0) + +#define VC7_REG_ODRV_EN(idx) (0x240 + (0x4 * (idx))) +#define VC7_REG_OUT_DIS BIT(0) + +struct vc7_driver_data; +static const struct regmap_config vc7_regmap_config; + +/* Supported Renesas VC7 models */ +enum vc7_model { + VC7_RC21008A, +}; + +struct vc7_chip_info { + const enum vc7_model model; + const unsigned int banks[VC7_NUM_BANKS]; + const unsigned int num_banks; + const unsigned int outputs[VC7_NUM_OUT]; + const unsigned int num_outputs; +}; + +/* + * Changing the APLL frequency is currently not supported. + * The APLL will consist of an opaque block between the XO and FOD/IODs and + * its frequency will be computed based on the current state of the device. + */ +struct vc7_apll_data { + struct clk *clk; + struct vc7_driver_data *vc7; + u8 xo_ib_h_div; + u8 en_doubler; + u16 apll_fb_div_int; + u32 apll_fb_div_frac; +}; + +struct vc7_fod_data { + struct clk_hw hw; + struct vc7_driver_data *vc7; + unsigned int num; + u32 fod_1st_int; + u32 fod_2nd_int; + u64 fod_frac; +}; + +struct vc7_iod_data { + struct clk_hw hw; + struct vc7_driver_data *vc7; + unsigned int num; + u32 iod_int; +}; + +struct vc7_out_data { + struct clk_hw hw; + struct vc7_driver_data *vc7; + unsigned int num; + unsigned int out_dis; +}; + +struct vc7_driver_data { + struct i2c_client *client; + struct regmap *regmap; + const struct vc7_chip_info *chip_info; + + struct clk *pin_xin; + struct vc7_apll_data clk_apll; + struct vc7_fod_data clk_fod[VC7_NUM_FOD]; + struct vc7_iod_data clk_iod[VC7_NUM_IOD]; + struct vc7_out_data clk_out[VC7_NUM_OUT]; +}; + +struct vc7_bank_src_map { + enum vc7_bank_src_type { + VC7_FOD, + VC7_IOD, + } type; + union _divider { + struct vc7_iod_data *iod; + struct vc7_fod_data *fod; + } src; +}; + +static struct clk_hw *vc7_of_clk_get(struct of_phandle_args *clkspec, + void *data) +{ + struct vc7_driver_data *vc7 = data; + unsigned int idx = clkspec->args[0]; + + if (idx >= vc7->chip_info->num_outputs) + return ERR_PTR(-EINVAL); + + return &vc7->clk_out[idx].hw; +} + +static const unsigned int RC21008A_index_to_output_mapping[] = { + 1, 2, 3, 6, 7, 8, 10, 11 +}; + +static int vc7_map_index_to_output(const enum vc7_model model, const unsigned int i) +{ + switch (model) { + case VC7_RC21008A: + return RC21008A_index_to_output_mapping[i]; + default: + return i; + } +} + +/* bank to output mapping, same across all variants */ +static const unsigned int output_bank_mapping[] = { + 0, /* Output 0 */ + 1, /* Output 1 */ + 2, /* Output 2 */ + 2, /* Output 3 */ + 3, /* Output 4 */ + 3, /* Output 5 */ + 3, /* Output 6 */ + 3, /* Output 7 */ + 4, /* Output 8 */ + 4, /* Output 9 */ + 5, /* Output 10 */ + 6 /* Output 11 */ +}; + +/** + * vc7_64_mul_64_to_128() - Multiply two u64 and return an unsigned 128-bit integer + * as an upper and lower part. + * + * @left: The left argument. + * @right: The right argument. + * @hi: The upper 64-bits of the 128-bit product. + * @lo: The lower 64-bits of the 128-bit product. + * + * From mul_64_64 in crypto/ecc.c:350 in the linux kernel, accessed in v5.17.2. + */ +static void vc7_64_mul_64_to_128(u64 left, u64 right, u64 *hi, u64 *lo) +{ + u64 a0 = left & 0xffffffffull; + u64 a1 = left >> 32; + u64 b0 = right & 0xffffffffull; + u64 b1 = right >> 32; + u64 m0 = a0 * b0; + u64 m1 = a0 * b1; + u64 m2 = a1 * b0; + u64 m3 = a1 * b1; + + m2 += (m0 >> 32); + m2 += m1; + + /* Overflow */ + if (m2 < m1) + m3 += 0x100000000ull; + + *lo = (m0 & 0xffffffffull) | (m2 << 32); + *hi = m3 + (m2 >> 32); +} + +/** + * vc7_128_div_64_to_64() - Divides a 128-bit uint by a 64-bit divisor, return a 64-bit quotient. + * + * @numhi: The uppper 64-bits of the dividend. + * @numlo: The lower 64-bits of the dividend. + * @den: The denominator (divisor). + * @r: The remainder, pass NULL if the remainder is not needed. + * + * Originally from libdivide, modified to use kernel u64/u32 types. + * + * See https://github.com/ridiculousfish/libdivide/blob/master/libdivide.h#L471. + * + * Return: The 64-bit quotient of the division. + * + * In case of overflow of division by zero, max(u64) is returned. + */ +static u64 vc7_128_div_64_to_64(u64 numhi, u64 numlo, u64 den, u64 *r) +{ + /* + * We work in base 2**32. + * A uint32 holds a single digit. A uint64 holds two digits. + * Our numerator is conceptually [num3, num2, num1, num0]. + * Our denominator is [den1, den0]. + */ + const u64 b = ((u64)1 << 32); + + /* The high and low digits of our computed quotient. */ + u32 q1, q0; + + /* The normalization shift factor */ + int shift; + + /* + * The high and low digits of our denominator (after normalizing). + * Also the low 2 digits of our numerator (after normalizing). + */ + u32 den1, den0, num1, num0; + + /* A partial remainder; */ + u64 rem; + + /* + * The estimated quotient, and its corresponding remainder (unrelated + * to true remainder). + */ + u64 qhat, rhat; + + /* Variables used to correct the estimated quotient. */ + u64 c1, c2; + + /* Check for overflow and divide by 0. */ + if (numhi >= den) { + if (r) + *r = ~0ull; + return ~0ull; + } + + /* + * Determine the normalization factor. We multiply den by this, so that + * its leading digit is at least half b. In binary this means just + * shifting left by the number of leading zeros, so that there's a 1 in + * the MSB. + * + * We also shift numer by the same amount. This cannot overflow because + * numhi < den. The expression (-shift & 63) is the same as (64 - + * shift), except it avoids the UB of shifting by 64. The funny bitwise + * 'and' ensures that numlo does not get shifted into numhi if shift is + * 0. clang 11 has an x86 codegen bug here: see LLVM bug 50118. The + * sequence below avoids it. + */ + shift = __builtin_clzll(den); + den <<= shift; + numhi <<= shift; + numhi |= (numlo >> (-shift & 63)) & (-(s64)shift >> 63); + numlo <<= shift; + + /* + * Extract the low digits of the numerator and both digits of the + * denominator. + */ + num1 = (u32)(numlo >> 32); + num0 = (u32)(numlo & 0xFFFFFFFFu); + den1 = (u32)(den >> 32); + den0 = (u32)(den & 0xFFFFFFFFu); + + /* + * We wish to compute q1 = [n3 n2 n1] / [d1 d0]. + * Estimate q1 as [n3 n2] / [d1], and then correct it. + * Note while qhat may be 2 digits, q1 is always 1 digit. + */ + qhat = div64_u64_rem(numhi, den1, &rhat); + c1 = qhat * den0; + c2 = rhat * b + num1; + if (c1 > c2) + qhat -= (c1 - c2 > den) ? 2 : 1; + q1 = (u32)qhat; + + /* Compute the true (partial) remainder. */ + rem = numhi * b + num1 - q1 * den; + + /* + * We wish to compute q0 = [rem1 rem0 n0] / [d1 d0]. + * Estimate q0 as [rem1 rem0] / [d1] and correct it. + */ + qhat = div64_u64_rem(rem, den1, &rhat); + c1 = qhat * den0; + c2 = rhat * b + num0; + if (c1 > c2) + qhat -= (c1 - c2 > den) ? 2 : 1; + q0 = (u32)qhat; + + /* Return remainder if requested. */ + if (r) + *r = (rem * b + num0 - q0 * den) >> shift; + return ((u64)q1 << 32) | q0; +} + +static int vc7_get_bank_clk(struct vc7_driver_data *vc7, + unsigned int bank_idx, + unsigned int output_bank_src, + struct vc7_bank_src_map *map) +{ + /* Mapping from Table 38 in datasheet */ + if (bank_idx == 0 || bank_idx == 1) { + switch (output_bank_src) { + case 0: + map->type = VC7_IOD, + map->src.iod = &vc7->clk_iod[0]; + return 0; + case 1: + map->type = VC7_IOD, + map->src.iod = &vc7->clk_iod[1]; + return 0; + case 4: + map->type = VC7_FOD, + map->src.fod = &vc7->clk_fod[0]; + return 0; + case 5: + map->type = VC7_FOD, + map->src.fod = &vc7->clk_fod[1]; + return 0; + default: + break; + } + } else if (bank_idx == 2) { + switch (output_bank_src) { + case 1: + map->type = VC7_IOD, + map->src.iod = &vc7->clk_iod[1]; + return 0; + case 4: + map->type = VC7_FOD, + map->src.fod = &vc7->clk_fod[0]; + return 0; + case 5: + map->type = VC7_FOD, + map->src.fod = &vc7->clk_fod[1]; + return 0; + default: + break; + } + } else if (bank_idx == 3) { + switch (output_bank_src) { + case 4: + map->type = VC7_FOD, + map->src.fod = &vc7->clk_fod[0]; + return 0; + case 5: + map->type = VC7_FOD, + map->src.fod = &vc7->clk_fod[1]; + return 0; + case 6: + map->type = VC7_FOD, + map->src.fod = &vc7->clk_fod[2]; + return 0; + default: + break; + } + } else if (bank_idx == 4) { + switch (output_bank_src) { + case 0: + /* CLKIN1 not supported in this driver */ + break; + case 2: + map->type = VC7_IOD, + map->src.iod = &vc7->clk_iod[2]; + return 0; + case 5: + map->type = VC7_FOD, + map->src.fod = &vc7->clk_fod[1]; + return 0; + case 6: + map->type = VC7_FOD, + map->src.fod = &vc7->clk_fod[2]; + return 0; + case 7: + /* CLKIN0 not supported in this driver */ + break; + default: + break; + } + } else if (bank_idx == 5) { + switch (output_bank_src) { + case 0: + /* CLKIN1 not supported in this driver */ + break; + case 1: + /* XIN_REFIN not supported in this driver */ + break; + case 2: + map->type = VC7_IOD, + map->src.iod = &vc7->clk_iod[2]; + return 0; + case 3: + map->type = VC7_IOD, + map->src.iod = &vc7->clk_iod[3]; + return 0; + case 5: + map->type = VC7_FOD, + map->src.fod = &vc7->clk_fod[1]; + return 0; + case 6: + map->type = VC7_FOD, + map->src.fod = &vc7->clk_fod[2]; + return 0; + case 7: + /* CLKIN0 not supported in this driver */ + break; + default: + break; + } + } else if (bank_idx == 6) { + switch (output_bank_src) { + case 0: + /* CLKIN1 not supported in this driver */ + break; + case 2: + map->type = VC7_IOD, + map->src.iod = &vc7->clk_iod[2]; + return 0; + case 3: + map->type = VC7_IOD, + map->src.iod = &vc7->clk_iod[3]; + return 0; + case 5: + map->type = VC7_FOD, + map->src.fod = &vc7->clk_fod[1]; + return 0; + case 6: + map->type = VC7_FOD, + map->src.fod = &vc7->clk_fod[2]; + return 0; + case 7: + /* CLKIN0 not supported in this driver */ + break; + default: + break; + } + } + + pr_warn("bank_src%d = %d is not supported\n", bank_idx, output_bank_src); + return -1; +} + +static int vc7_read_apll(struct vc7_driver_data *vc7) +{ + int err; + u32 val32; + u16 val16; + + err = regmap_bulk_read(vc7->regmap, + VC7_REG_XO_CNFG, + (u32 *)&val32, + VC7_REG_XO_CNFG_COUNT); + if (err) { + dev_err(&vc7->client->dev, "failed to read XO_CNFG\n"); + return err; + } + + vc7->clk_apll.xo_ib_h_div = (val32 & VC7_REG_XO_IB_H_DIV_MASK) + >> VC7_REG_XO_IB_H_DIV_SHIFT; + + err = regmap_read(vc7->regmap, + VC7_REG_APLL_CNFG, + &val32); + if (err) { + dev_err(&vc7->client->dev, "failed to read APLL_CNFG\n"); + return err; + } + + vc7->clk_apll.en_doubler = val32 & VC7_REG_APLL_EN_DOUBLER; + + err = regmap_bulk_read(vc7->regmap, + VC7_REG_APLL_FB_DIV_FRAC, + (u32 *)&val32, + VC7_REG_APLL_FB_DIV_FRAC_COUNT); + if (err) { + dev_err(&vc7->client->dev, "failed to read APLL_FB_DIV_FRAC\n"); + return err; + } + + vc7->clk_apll.apll_fb_div_frac = val32 & VC7_REG_APLL_FB_DIV_FRAC_MASK; + + err = regmap_bulk_read(vc7->regmap, + VC7_REG_APLL_FB_DIV_INT, + (u16 *)&val16, + VC7_REG_APLL_FB_DIV_INT_COUNT); + if (err) { + dev_err(&vc7->client->dev, "failed to read APLL_FB_DIV_INT\n"); + return err; + } + + vc7->clk_apll.apll_fb_div_int = val16 & VC7_REG_APLL_FB_DIV_INT_MASK; + + return 0; +} + +static int vc7_read_fod(struct vc7_driver_data *vc7, unsigned int idx) +{ + int err; + u64 val; + + err = regmap_bulk_read(vc7->regmap, + VC7_REG_FOD_INT_CNFG(idx), + (u64 *)&val, + VC7_REG_FOD_INT_CNFG_COUNT); + if (err) { + dev_err(&vc7->client->dev, "failed to read FOD%d\n", idx); + return err; + } + + vc7->clk_fod[idx].fod_1st_int = (val & VC7_REG_FOD_1ST_INT_MASK); + vc7->clk_fod[idx].fod_2nd_int = + (val & VC7_REG_FOD_2ND_INT_MASK) >> VC7_REG_FOD_2ND_INT_SHIFT; + vc7->clk_fod[idx].fod_frac = (val & VC7_REG_FOD_FRAC_MASK) + >> VC7_REG_FOD_FRAC_SHIFT; + + return 0; +} + +static int vc7_write_fod(struct vc7_driver_data *vc7, unsigned int idx) +{ + int err; + u64 val; + + /* + * FOD dividers are part of an atomic group where fod_1st_int, + * fod_2nd_int, and fod_frac must be written together. The new divider + * is applied when the MSB of fod_frac is written. + */ + + err = regmap_bulk_read(vc7->regmap, + VC7_REG_FOD_INT_CNFG(idx), + (u64 *)&val, + VC7_REG_FOD_INT_CNFG_COUNT); + if (err) { + dev_err(&vc7->client->dev, "failed to read FOD%d\n", idx); + return err; + } + + val = u64_replace_bits(val, + vc7->clk_fod[idx].fod_1st_int, + VC7_REG_FOD_1ST_INT_MASK); + val = u64_replace_bits(val, + vc7->clk_fod[idx].fod_2nd_int, + VC7_REG_FOD_2ND_INT_MASK); + val = u64_replace_bits(val, + vc7->clk_fod[idx].fod_frac, + VC7_REG_FOD_FRAC_MASK); + + err = regmap_bulk_write(vc7->regmap, + VC7_REG_FOD_INT_CNFG(idx), + (u64 *)&val, + sizeof(u64)); + if (err) { + dev_err(&vc7->client->dev, "failed to write FOD%d\n", idx); + return err; + } + + return 0; +} + +static int vc7_read_iod(struct vc7_driver_data *vc7, unsigned int idx) +{ + int err; + u32 val; + + err = regmap_bulk_read(vc7->regmap, + VC7_REG_IOD_INT_CNFG(idx), + (u32 *)&val, + VC7_REG_IOD_INT_CNFG_COUNT); + if (err) { + dev_err(&vc7->client->dev, "failed to read IOD%d\n", idx); + return err; + } + + vc7->clk_iod[idx].iod_int = (val & VC7_REG_IOD_INT_MASK); + + return 0; +} + +static int vc7_write_iod(struct vc7_driver_data *vc7, unsigned int idx) +{ + int err; + u32 val; + + /* + * IOD divider field is atomic and all bits must be written. + * The new divider is applied when the MSB of iod_int is written. + */ + + err = regmap_bulk_read(vc7->regmap, + VC7_REG_IOD_INT_CNFG(idx), + (u32 *)&val, + VC7_REG_IOD_INT_CNFG_COUNT); + if (err) { + dev_err(&vc7->client->dev, "failed to read IOD%d\n", idx); + return err; + } + + val = u32_replace_bits(val, + vc7->clk_iod[idx].iod_int, + VC7_REG_IOD_INT_MASK); + + err = regmap_bulk_write(vc7->regmap, + VC7_REG_IOD_INT_CNFG(idx), + (u32 *)&val, + sizeof(u32)); + if (err) { + dev_err(&vc7->client->dev, "failed to write IOD%d\n", idx); + return err; + } + + return 0; +} + +static int vc7_read_output(struct vc7_driver_data *vc7, unsigned int idx) +{ + int err; + unsigned int val, out_num; + + out_num = vc7_map_index_to_output(vc7->chip_info->model, idx); + err = regmap_read(vc7->regmap, + VC7_REG_ODRV_EN(out_num), + &val); + if (err) { + dev_err(&vc7->client->dev, "failed to read ODRV_EN[%d]\n", idx); + return err; + } + + vc7->clk_out[idx].out_dis = val & VC7_REG_OUT_DIS; + + return 0; +} + +static int vc7_write_output(struct vc7_driver_data *vc7, unsigned int idx) +{ + int err; + unsigned int out_num; + + out_num = vc7_map_index_to_output(vc7->chip_info->model, idx); + err = regmap_write_bits(vc7->regmap, + VC7_REG_ODRV_EN(out_num), + VC7_REG_OUT_DIS, + vc7->clk_out[idx].out_dis); + + if (err) { + dev_err(&vc7->client->dev, "failed to write ODRV_EN[%d]\n", idx); + return err; + } + + return 0; +} + +static unsigned long vc7_get_apll_rate(struct vc7_driver_data *vc7) +{ + int err; + unsigned long xtal_rate; + u64 refin_div, apll_rate; + + xtal_rate = clk_get_rate(vc7->pin_xin); + err = vc7_read_apll(vc7); + if (err) { + dev_err(&vc7->client->dev, "unable to read apll\n"); + return err; + } + + /* 0 is bypassed, 1 is reserved */ + if (vc7->clk_apll.xo_ib_h_div < 2) + refin_div = xtal_rate; + else + refin_div = div64_u64(xtal_rate, vc7->clk_apll.xo_ib_h_div); + + if (vc7->clk_apll.en_doubler) + refin_div *= 2; + + /* divider = int + (frac / 2^27) */ + apll_rate = (refin_div * vc7->clk_apll.apll_fb_div_int) + + ((refin_div * vc7->clk_apll.apll_fb_div_frac) >> VC7_APLL_DENOMINATOR_BITS); + + pr_debug("%s - xo_ib_h_div: %u, apll_fb_div_int: %u, apll_fb_div_frac: %u\n", + __func__, vc7->clk_apll.xo_ib_h_div, vc7->clk_apll.apll_fb_div_int, + vc7->clk_apll.apll_fb_div_frac); + pr_debug("%s - refin_div: %llu, apll rate: %llu\n", + __func__, refin_div, apll_rate); + + return apll_rate; +} + +static void vc7_calc_iod_divider(unsigned long rate, unsigned long parent_rate, + u32 *divider) +{ + *divider = DIV_ROUND_UP(parent_rate, rate); + if (*divider < VC7_IOD_MIN_DIVISOR) + *divider = VC7_IOD_MIN_DIVISOR; + if (*divider > VC7_IOD_MAX_DIVISOR) + *divider = VC7_IOD_MAX_DIVISOR; +} + +static void vc7_calc_fod_1st_stage(unsigned long rate, unsigned long parent_rate, + u32 *div_int, u64 *div_frac) +{ + u64 rem; + + *div_int = (u32)div64_u64_rem(parent_rate, rate, &rem); + *div_frac = div64_u64(rem << VC7_FOD_DENOMINATOR_BITS, rate); +} + +static unsigned long vc7_calc_fod_1st_stage_rate(unsigned long parent_rate, + u32 fod_1st_int, u64 fod_frac) +{ + u64 numer, denom, hi, lo, divisor; + + numer = fod_frac; + denom = BIT_ULL(VC7_FOD_DENOMINATOR_BITS); + + if (fod_frac) { + vc7_64_mul_64_to_128(parent_rate, denom, &hi, &lo); + divisor = ((u64)fod_1st_int * denom) + numer; + return vc7_128_div_64_to_64(hi, lo, divisor, NULL); + } + + return div64_u64(parent_rate, fod_1st_int); +} + +static unsigned long vc7_calc_fod_2nd_stage_rate(unsigned long parent_rate, + u32 fod_1st_int, u32 fod_2nd_int, u64 fod_frac) +{ + unsigned long fod_1st_stage_rate; + + fod_1st_stage_rate = vc7_calc_fod_1st_stage_rate(parent_rate, fod_1st_int, fod_frac); + + if (fod_2nd_int < 2) + return fod_1st_stage_rate; + + /* + * There is a div-by-2 preceding the 2nd stage integer divider + * (not shown on block diagram) so the actual 2nd stage integer + * divisor is 2 * N. + */ + return div64_u64(fod_1st_stage_rate >> 1, fod_2nd_int); +} + +static void vc7_calc_fod_divider(unsigned long rate, unsigned long parent_rate, + u32 *fod_1st_int, u32 *fod_2nd_int, u64 *fod_frac) +{ + unsigned int allow_frac, i, best_frac_i; + unsigned long first_stage_rate; + + vc7_calc_fod_1st_stage(rate, parent_rate, fod_1st_int, fod_frac); + first_stage_rate = vc7_calc_fod_1st_stage_rate(parent_rate, *fod_1st_int, *fod_frac); + + *fod_2nd_int = 0; + + /* Do we need the second stage integer divider? */ + if (first_stage_rate < VC7_FOD_1ST_STAGE_RATE_MIN) { + allow_frac = 0; + best_frac_i = VC7_FOD_2ND_INT_MIN; + + for (i = VC7_FOD_2ND_INT_MIN; i <= VC7_FOD_2ND_INT_MAX; i++) { + /* + * 1) There is a div-by-2 preceding the 2nd stage integer divider + * (not shown on block diagram) so the actual 2nd stage integer + * divisor is 2 * N. + * 2) Attempt to find an integer solution first. This means stepping + * through each 2nd stage integer and recalculating the 1st stage + * until the 1st stage frequency is out of bounds. If no integer + * solution is found, use the best fractional solution. + */ + vc7_calc_fod_1st_stage(parent_rate, rate * 2 * i, fod_1st_int, fod_frac); + first_stage_rate = vc7_calc_fod_1st_stage_rate(parent_rate, + *fod_1st_int, + *fod_frac); + + /* Remember the first viable fractional solution */ + if (best_frac_i == VC7_FOD_2ND_INT_MIN && + first_stage_rate > VC7_FOD_1ST_STAGE_RATE_MIN) { + best_frac_i = i; + } + + /* Is the divider viable? Prefer integer solutions over fractional. */ + if (*fod_1st_int < VC7_FOD_1ST_INT_MAX && + first_stage_rate >= VC7_FOD_1ST_STAGE_RATE_MIN && + (allow_frac || *fod_frac == 0)) { + *fod_2nd_int = i; + break; + } + + /* Ran out of divisors or the 1st stage frequency is out of range */ + if (i >= VC7_FOD_2ND_INT_MAX || + first_stage_rate > VC7_FOD_1ST_STAGE_RATE_MAX) { + allow_frac = 1; + i = best_frac_i; + + /* Restore the best frac and rerun the loop for the last time */ + if (best_frac_i != VC7_FOD_2ND_INT_MIN) + i--; + + continue; + } + } + } +} + +static unsigned long vc7_fod_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) +{ + struct vc7_fod_data *fod = container_of(hw, struct vc7_fod_data, hw); + struct vc7_driver_data *vc7 = fod->vc7; + int err; + unsigned long fod_rate; + + err = vc7_read_fod(vc7, fod->num); + if (err) { + dev_err(&vc7->client->dev, "error reading registers for %s\n", + clk_hw_get_name(hw)); + return err; + } + + pr_debug("%s - %s: parent_rate: %lu\n", __func__, clk_hw_get_name(hw), parent_rate); + + fod_rate = vc7_calc_fod_2nd_stage_rate(parent_rate, fod->fod_1st_int, + fod->fod_2nd_int, fod->fod_frac); + + pr_debug("%s - %s: fod_1st_int: %u, fod_2nd_int: %u, fod_frac: %llu\n", + __func__, clk_hw_get_name(hw), + fod->fod_1st_int, fod->fod_2nd_int, fod->fod_frac); + pr_debug("%s - %s rate: %lu\n", __func__, clk_hw_get_name(hw), fod_rate); + + return fod_rate; +} + +static long vc7_fod_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *parent_rate) +{ + struct vc7_fod_data *fod = container_of(hw, struct vc7_fod_data, hw); + unsigned long fod_rate; + + pr_debug("%s - %s: requested rate: %lu, parent_rate: %lu\n", + __func__, clk_hw_get_name(hw), rate, *parent_rate); + + vc7_calc_fod_divider(rate, *parent_rate, + &fod->fod_1st_int, &fod->fod_2nd_int, &fod->fod_frac); + fod_rate = vc7_calc_fod_2nd_stage_rate(*parent_rate, fod->fod_1st_int, + fod->fod_2nd_int, fod->fod_frac); + + pr_debug("%s - %s: fod_1st_int: %u, fod_2nd_int: %u, fod_frac: %llu\n", + __func__, clk_hw_get_name(hw), + fod->fod_1st_int, fod->fod_2nd_int, fod->fod_frac); + pr_debug("%s - %s rate: %lu\n", __func__, clk_hw_get_name(hw), fod_rate); + + return fod_rate; +} + +static int vc7_fod_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) +{ + struct vc7_fod_data *fod = container_of(hw, struct vc7_fod_data, hw); + struct vc7_driver_data *vc7 = fod->vc7; + unsigned long fod_rate; + + pr_debug("%s - %s: rate: %lu, parent_rate: %lu\n", + __func__, clk_hw_get_name(hw), rate, parent_rate); + + if (rate < VC7_FOD_RATE_MIN || rate > VC7_FOD_RATE_MAX) { + dev_err(&vc7->client->dev, + "requested frequency %lu Hz for %s is out of range\n", + rate, clk_hw_get_name(hw)); + return -EINVAL; + } + + vc7_write_fod(vc7, fod->num); + + fod_rate = vc7_calc_fod_2nd_stage_rate(parent_rate, fod->fod_1st_int, + fod->fod_2nd_int, fod->fod_frac); + + pr_debug("%s - %s: fod_1st_int: %u, fod_2nd_int: %u, fod_frac: %llu\n", + __func__, clk_hw_get_name(hw), + fod->fod_1st_int, fod->fod_2nd_int, fod->fod_frac); + pr_debug("%s - %s rate: %lu\n", __func__, clk_hw_get_name(hw), fod_rate); + + return 0; +} + +static const struct clk_ops vc7_fod_ops = { + .recalc_rate = vc7_fod_recalc_rate, + .round_rate = vc7_fod_round_rate, + .set_rate = vc7_fod_set_rate, +}; + +static unsigned long vc7_iod_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) +{ + struct vc7_iod_data *iod = container_of(hw, struct vc7_iod_data, hw); + struct vc7_driver_data *vc7 = iod->vc7; + int err; + unsigned long iod_rate; + + err = vc7_read_iod(vc7, iod->num); + if (err) { + dev_err(&vc7->client->dev, "error reading registers for %s\n", + clk_hw_get_name(hw)); + return err; + } + + iod_rate = div64_u64(parent_rate, iod->iod_int); + + pr_debug("%s - %s: iod_int: %u\n", __func__, clk_hw_get_name(hw), iod->iod_int); + pr_debug("%s - %s rate: %lu\n", __func__, clk_hw_get_name(hw), iod_rate); + + return iod_rate; +} + +static long vc7_iod_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *parent_rate) +{ + struct vc7_iod_data *iod = container_of(hw, struct vc7_iod_data, hw); + unsigned long iod_rate; + + pr_debug("%s - %s: requested rate: %lu, parent_rate: %lu\n", + __func__, clk_hw_get_name(hw), rate, *parent_rate); + + vc7_calc_iod_divider(rate, *parent_rate, &iod->iod_int); + iod_rate = div64_u64(*parent_rate, iod->iod_int); + + pr_debug("%s - %s: iod_int: %u\n", __func__, clk_hw_get_name(hw), iod->iod_int); + pr_debug("%s - %s rate: %ld\n", __func__, clk_hw_get_name(hw), iod_rate); + + return iod_rate; +} + +static int vc7_iod_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) +{ + struct vc7_iod_data *iod = container_of(hw, struct vc7_iod_data, hw); + struct vc7_driver_data *vc7 = iod->vc7; + unsigned long iod_rate; + + pr_debug("%s - %s: rate: %lu, parent_rate: %lu\n", + __func__, clk_hw_get_name(hw), rate, parent_rate); + + if (rate < VC7_IOD_RATE_MIN || rate > VC7_IOD_RATE_MAX) { + dev_err(&vc7->client->dev, + "requested frequency %lu Hz for %s is out of range\n", + rate, clk_hw_get_name(hw)); + return -EINVAL; + } + + vc7_write_iod(vc7, iod->num); + + iod_rate = div64_u64(parent_rate, iod->iod_int); + + pr_debug("%s - %s: iod_int: %u\n", __func__, clk_hw_get_name(hw), iod->iod_int); + pr_debug("%s - %s rate: %ld\n", __func__, clk_hw_get_name(hw), iod_rate); + + return 0; +} + +static const struct clk_ops vc7_iod_ops = { + .recalc_rate = vc7_iod_recalc_rate, + .round_rate = vc7_iod_round_rate, + .set_rate = vc7_iod_set_rate, +}; + +static int vc7_clk_out_prepare(struct clk_hw *hw) +{ + struct vc7_out_data *out = container_of(hw, struct vc7_out_data, hw); + struct vc7_driver_data *vc7 = out->vc7; + int err; + + out->out_dis = 0; + + err = vc7_write_output(vc7, out->num); + if (err) { + dev_err(&vc7->client->dev, "error writing registers for %s\n", + clk_hw_get_name(hw)); + return err; + } + + pr_debug("%s - %s: clk prepared\n", __func__, clk_hw_get_name(hw)); + + return 0; +} + +static void vc7_clk_out_unprepare(struct clk_hw *hw) +{ + struct vc7_out_data *out = container_of(hw, struct vc7_out_data, hw); + struct vc7_driver_data *vc7 = out->vc7; + int err; + + out->out_dis = 1; + + err = vc7_write_output(vc7, out->num); + if (err) { + dev_err(&vc7->client->dev, "error writing registers for %s\n", + clk_hw_get_name(hw)); + return; + } + + pr_debug("%s - %s: clk unprepared\n", __func__, clk_hw_get_name(hw)); +} + +static int vc7_clk_out_is_enabled(struct clk_hw *hw) +{ + struct vc7_out_data *out = container_of(hw, struct vc7_out_data, hw); + struct vc7_driver_data *vc7 = out->vc7; + int err, is_enabled; + + err = vc7_read_output(vc7, out->num); + if (err) { + dev_err(&vc7->client->dev, "error reading registers for %s\n", + clk_hw_get_name(hw)); + return err; + } + + is_enabled = !out->out_dis; + + pr_debug("%s - %s: is_enabled=%d\n", __func__, clk_hw_get_name(hw), is_enabled); + + return is_enabled; +} + +static const struct clk_ops vc7_clk_out_ops = { + .prepare = vc7_clk_out_prepare, + .unprepare = vc7_clk_out_unprepare, + .is_enabled = vc7_clk_out_is_enabled, +}; + +static int vc7_probe(struct i2c_client *client) +{ + struct vc7_driver_data *vc7; + struct clk_init_data clk_init; + struct vc7_bank_src_map bank_src_map; + const char *node_name, *apll_name; + const char *parent_names[1]; + unsigned int i, val, bank_idx, out_num; + unsigned long apll_rate; + int ret; + + vc7 = devm_kzalloc(&client->dev, sizeof(*vc7), GFP_KERNEL); + if (!vc7) + return -ENOMEM; + + i2c_set_clientdata(client, vc7); + vc7->client = client; + vc7->chip_info = of_device_get_match_data(&client->dev); + + vc7->pin_xin = devm_clk_get(&client->dev, "xin"); + if (PTR_ERR(vc7->pin_xin) == -EPROBE_DEFER) { + return dev_err_probe(&client->dev, -EPROBE_DEFER, + "xin not specified\n"); + } + + vc7->regmap = devm_regmap_init_i2c(client, &vc7_regmap_config); + if (IS_ERR(vc7->regmap)) { + return dev_err_probe(&client->dev, PTR_ERR(vc7->regmap), + "failed to allocate register map\n"); + } + + if (of_property_read_string(client->dev.of_node, "clock-output-names", + &node_name)) + node_name = client->dev.of_node->name; + + /* Register APLL */ + apll_rate = vc7_get_apll_rate(vc7); + apll_name = kasprintf(GFP_KERNEL, "%s_apll", node_name); + vc7->clk_apll.clk = clk_register_fixed_rate(&client->dev, apll_name, + __clk_get_name(vc7->pin_xin), + 0, apll_rate); + kfree(apll_name); /* ccf made a copy of the name */ + if (IS_ERR(vc7->clk_apll.clk)) { + return dev_err_probe(&client->dev, PTR_ERR(vc7->clk_apll.clk), + "failed to register apll\n"); + } + + /* Register FODs */ + for (i = 0; i < VC7_NUM_FOD; i++) { + memset(&clk_init, 0, sizeof(clk_init)); + clk_init.name = kasprintf(GFP_KERNEL, "%s_fod%d", node_name, i); + clk_init.ops = &vc7_fod_ops; + clk_init.parent_names = parent_names; + parent_names[0] = __clk_get_name(vc7->clk_apll.clk); + clk_init.num_parents = 1; + vc7->clk_fod[i].num = i; + vc7->clk_fod[i].vc7 = vc7; + vc7->clk_fod[i].hw.init = &clk_init; + ret = devm_clk_hw_register(&client->dev, &vc7->clk_fod[i].hw); + if (ret) + goto err_clk_register; + kfree(clk_init.name); /* ccf made a copy of the name */ + } + + /* Register IODs */ + for (i = 0; i < VC7_NUM_IOD; i++) { + memset(&clk_init, 0, sizeof(clk_init)); + clk_init.name = kasprintf(GFP_KERNEL, "%s_iod%d", node_name, i); + clk_init.ops = &vc7_iod_ops; + clk_init.parent_names = parent_names; + parent_names[0] = __clk_get_name(vc7->clk_apll.clk); + clk_init.num_parents = 1; + vc7->clk_iod[i].num = i; + vc7->clk_iod[i].vc7 = vc7; + vc7->clk_iod[i].hw.init = &clk_init; + ret = devm_clk_hw_register(&client->dev, &vc7->clk_iod[i].hw); + if (ret) + goto err_clk_register; + kfree(clk_init.name); /* ccf made a copy of the name */ + } + + /* Register outputs */ + for (i = 0; i < vc7->chip_info->num_outputs; i++) { + out_num = vc7_map_index_to_output(vc7->chip_info->model, i); + + /* + * This driver does not support remapping FOD/IOD to banks. + * The device state is read and the driver is setup to match + * the device's existing mapping. + */ + bank_idx = output_bank_mapping[out_num]; + + regmap_read(vc7->regmap, VC7_REG_OUT_BANK_CNFG(bank_idx), &val); + val &= VC7_REG_OUTPUT_BANK_SRC_MASK; + + memset(&bank_src_map, 0, sizeof(bank_src_map)); + ret = vc7_get_bank_clk(vc7, bank_idx, val, &bank_src_map); + if (ret) { + dev_err_probe(&client->dev, ret, + "unable to register output %d\n", i); + return ret; + } + + switch (bank_src_map.type) { + case VC7_FOD: + parent_names[0] = clk_hw_get_name(&bank_src_map.src.fod->hw); + break; + case VC7_IOD: + parent_names[0] = clk_hw_get_name(&bank_src_map.src.iod->hw); + break; + } + + memset(&clk_init, 0, sizeof(clk_init)); + clk_init.name = kasprintf(GFP_KERNEL, "%s_out%d", node_name, i); + clk_init.ops = &vc7_clk_out_ops; + clk_init.flags = CLK_SET_RATE_PARENT; + clk_init.parent_names = parent_names; + clk_init.num_parents = 1; + vc7->clk_out[i].num = i; + vc7->clk_out[i].vc7 = vc7; + vc7->clk_out[i].hw.init = &clk_init; + ret = devm_clk_hw_register(&client->dev, &vc7->clk_out[i].hw); + if (ret) + goto err_clk_register; + kfree(clk_init.name); /* ccf made a copy of the name */ + } + + ret = of_clk_add_hw_provider(client->dev.of_node, vc7_of_clk_get, vc7); + if (ret) { + dev_err_probe(&client->dev, ret, "unable to add clk provider\n"); + goto err_clk; + } + + return ret; + +err_clk_register: + dev_err_probe(&client->dev, ret, + "unable to register %s\n", clk_init.name); + kfree(clk_init.name); /* ccf made a copy of the name */ +err_clk: + clk_unregister_fixed_rate(vc7->clk_apll.clk); + return ret; +} + +static void vc7_remove(struct i2c_client *client) +{ + struct vc7_driver_data *vc7 = i2c_get_clientdata(client); + + of_clk_del_provider(client->dev.of_node); + clk_unregister_fixed_rate(vc7->clk_apll.clk); +} + +static bool vc7_volatile_reg(struct device *dev, unsigned int reg) +{ + if (reg == VC7_PAGE_ADDR) + return false; + + return true; +} + +static const struct vc7_chip_info vc7_rc21008a_info = { + .model = VC7_RC21008A, + .num_banks = 6, + .num_outputs = 8, +}; + +static struct regmap_range_cfg vc7_range_cfg[] = { +{ + .range_min = 0, + .range_max = VC7_MAX_REG, + .selector_reg = VC7_PAGE_ADDR, + .selector_mask = 0xFF, + .selector_shift = 0, + .window_start = 0, + .window_len = VC7_PAGE_WINDOW, +}}; + +static const struct regmap_config vc7_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = VC7_MAX_REG, + .ranges = vc7_range_cfg, + .num_ranges = ARRAY_SIZE(vc7_range_cfg), + .volatile_reg = vc7_volatile_reg, + .cache_type = REGCACHE_RBTREE, + .can_multi_write = true, + .reg_format_endian = REGMAP_ENDIAN_LITTLE, + .val_format_endian = REGMAP_ENDIAN_LITTLE, +}; + +static const struct i2c_device_id vc7_i2c_id[] = { + { "rc21008a", .driver_data = (kernel_ulong_t)&vc7_rc21008a_info }, + {} +}; +MODULE_DEVICE_TABLE(i2c, vc7_i2c_id); + +static const struct of_device_id vc7_of_match[] = { + { .compatible = "renesas,rc21008a", .data = &vc7_rc21008a_info }, + {} +}; +MODULE_DEVICE_TABLE(of, vc7_of_match); + +static struct i2c_driver vc7_i2c_driver = { + .driver = { + .name = "vc7", + .of_match_table = vc7_of_match, + }, + .probe_new = vc7_probe, + .remove = vc7_remove, + .id_table = vc7_i2c_id, +}; +module_i2c_driver(vc7_i2c_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Alex Helms <alexander.helms.jy@renesas.com"); +MODULE_DESCRIPTION("Renesas Versaclock7 common clock framework driver"); |