// SPDX-License-Identifier: GPL-2.0-only /* * Analog Devices Generic AXI DAC IP core * Link: https://wiki.analog.com/resources/fpga/docs/axi_dac_ip * * Copyright 2016-2024 Analog Devices Inc. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * Register definitions: * https://wiki.analog.com/resources/fpga/docs/axi_dac_ip#register_map */ /* Base controls */ #define AXI_DAC_REG_CONFIG 0x0c #define AXI_DDS_DISABLE BIT(6) /* DAC controls */ #define AXI_DAC_REG_RSTN 0x0040 #define AXI_DAC_RSTN_CE_N BIT(2) #define AXI_DAC_RSTN_MMCM_RSTN BIT(1) #define AXI_DAC_RSTN_RSTN BIT(0) #define AXI_DAC_REG_CNTRL_1 0x0044 #define AXI_DAC_SYNC BIT(0) #define AXI_DAC_REG_CNTRL_2 0x0048 #define ADI_DAC_R1_MODE BIT(4) #define AXI_DAC_DRP_STATUS 0x0074 #define AXI_DAC_DRP_LOCKED BIT(17) /* DAC Channel controls */ #define AXI_DAC_REG_CHAN_CNTRL_1(c) (0x0400 + (c) * 0x40) #define AXI_DAC_REG_CHAN_CNTRL_3(c) (0x0408 + (c) * 0x40) #define AXI_DAC_SCALE_SIGN BIT(15) #define AXI_DAC_SCALE_INT BIT(14) #define AXI_DAC_SCALE GENMASK(14, 0) #define AXI_DAC_REG_CHAN_CNTRL_2(c) (0x0404 + (c) * 0x40) #define AXI_DAC_REG_CHAN_CNTRL_4(c) (0x040c + (c) * 0x40) #define AXI_DAC_PHASE GENMASK(31, 16) #define AXI_DAC_FREQUENCY GENMASK(15, 0) #define AXI_DAC_REG_CHAN_CNTRL_7(c) (0x0418 + (c) * 0x40) #define AXI_DAC_DATA_SEL GENMASK(3, 0) /* 360 degrees in rad */ #define AXI_DAC_2_PI_MEGA 6283190 enum { AXI_DAC_DATA_INTERNAL_TONE, AXI_DAC_DATA_DMA = 2, }; struct axi_dac_state { struct regmap *regmap; struct device *dev; /* * lock to protect multiple accesses to the device registers and global * data/variables. */ struct mutex lock; u64 dac_clk; u32 reg_config; bool int_tone; }; static int axi_dac_enable(struct iio_backend *back) { struct axi_dac_state *st = iio_backend_get_priv(back); unsigned int __val; int ret; guard(mutex)(&st->lock); ret = regmap_set_bits(st->regmap, AXI_DAC_REG_RSTN, AXI_DAC_RSTN_MMCM_RSTN); if (ret) return ret; /* * Make sure the DRP (Dynamic Reconfiguration Port) is locked. Not all * designs really use it but if they don't we still get the lock bit * set. So let's do it all the time so the code is generic. */ ret = regmap_read_poll_timeout(st->regmap, AXI_DAC_DRP_STATUS, __val, __val & AXI_DAC_DRP_LOCKED, 100, 1000); if (ret) return ret; return regmap_set_bits(st->regmap, AXI_DAC_REG_RSTN, AXI_DAC_RSTN_RSTN | AXI_DAC_RSTN_MMCM_RSTN); } static void axi_dac_disable(struct iio_backend *back) { struct axi_dac_state *st = iio_backend_get_priv(back); guard(mutex)(&st->lock); regmap_write(st->regmap, AXI_DAC_REG_RSTN, 0); } static struct iio_buffer *axi_dac_request_buffer(struct iio_backend *back, struct iio_dev *indio_dev) { struct axi_dac_state *st = iio_backend_get_priv(back); const char *dma_name; if (device_property_read_string(st->dev, "dma-names", &dma_name)) dma_name = "tx"; return iio_dmaengine_buffer_setup_ext(st->dev, indio_dev, dma_name, IIO_BUFFER_DIRECTION_OUT); } static void axi_dac_free_buffer(struct iio_backend *back, struct iio_buffer *buffer) { iio_dmaengine_buffer_free(buffer); } enum { AXI_DAC_FREQ_TONE_1, AXI_DAC_FREQ_TONE_2, AXI_DAC_SCALE_TONE_1, AXI_DAC_SCALE_TONE_2, AXI_DAC_PHASE_TONE_1, AXI_DAC_PHASE_TONE_2, }; static int __axi_dac_frequency_get(struct axi_dac_state *st, unsigned int chan, unsigned int tone_2, unsigned int *freq) { u32 reg, raw; int ret; if (!st->dac_clk) { dev_err(st->dev, "Sampling rate is 0...\n"); return -EINVAL; } if (tone_2) reg = AXI_DAC_REG_CHAN_CNTRL_4(chan); else reg = AXI_DAC_REG_CHAN_CNTRL_2(chan); ret = regmap_read(st->regmap, reg, &raw); if (ret) return ret; raw = FIELD_GET(AXI_DAC_FREQUENCY, raw); *freq = DIV_ROUND_CLOSEST_ULL(raw * st->dac_clk, BIT(16)); return 0; } static int axi_dac_frequency_get(struct axi_dac_state *st, const struct iio_chan_spec *chan, char *buf, unsigned int tone_2) { unsigned int freq; int ret; scoped_guard(mutex, &st->lock) { ret = __axi_dac_frequency_get(st, chan->channel, tone_2, &freq); if (ret) return ret; } return sysfs_emit(buf, "%u\n", freq); } static int axi_dac_scale_get(struct axi_dac_state *st, const struct iio_chan_spec *chan, char *buf, unsigned int tone_2) { unsigned int scale, sign; int ret, vals[2]; u32 reg, raw; if (tone_2) reg = AXI_DAC_REG_CHAN_CNTRL_3(chan->channel); else reg = AXI_DAC_REG_CHAN_CNTRL_1(chan->channel); ret = regmap_read(st->regmap, reg, &raw); if (ret) return ret; sign = FIELD_GET(AXI_DAC_SCALE_SIGN, raw); raw = FIELD_GET(AXI_DAC_SCALE, raw); scale = DIV_ROUND_CLOSEST_ULL((u64)raw * MEGA, AXI_DAC_SCALE_INT); vals[0] = scale / MEGA; vals[1] = scale % MEGA; if (sign) { vals[0] *= -1; if (!vals[0]) vals[1] *= -1; } return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, ARRAY_SIZE(vals), vals); } static int axi_dac_phase_get(struct axi_dac_state *st, const struct iio_chan_spec *chan, char *buf, unsigned int tone_2) { u32 reg, raw, phase; int ret, vals[2]; if (tone_2) reg = AXI_DAC_REG_CHAN_CNTRL_4(chan->channel); else reg = AXI_DAC_REG_CHAN_CNTRL_2(chan->channel); ret = regmap_read(st->regmap, reg, &raw); if (ret) return ret; raw = FIELD_GET(AXI_DAC_PHASE, raw); phase = DIV_ROUND_CLOSEST_ULL((u64)raw * AXI_DAC_2_PI_MEGA, U16_MAX); vals[0] = phase / MEGA; vals[1] = phase % MEGA; return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, ARRAY_SIZE(vals), vals); } static int __axi_dac_frequency_set(struct axi_dac_state *st, unsigned int chan, u64 sample_rate, unsigned int freq, unsigned int tone_2) { u32 reg; u16 raw; int ret; if (!sample_rate || freq > sample_rate / 2) { dev_err(st->dev, "Invalid frequency(%u) dac_clk(%llu)\n", freq, sample_rate); return -EINVAL; } if (tone_2) reg = AXI_DAC_REG_CHAN_CNTRL_4(chan); else reg = AXI_DAC_REG_CHAN_CNTRL_2(chan); raw = DIV64_U64_ROUND_CLOSEST((u64)freq * BIT(16), sample_rate); ret = regmap_update_bits(st->regmap, reg, AXI_DAC_FREQUENCY, raw); if (ret) return ret; /* synchronize channels */ return regmap_set_bits(st->regmap, AXI_DAC_REG_CNTRL_1, AXI_DAC_SYNC); } static int axi_dac_frequency_set(struct axi_dac_state *st, const struct iio_chan_spec *chan, const char *buf, size_t len, unsigned int tone_2) { unsigned int freq; int ret; ret = kstrtou32(buf, 10, &freq); if (ret) return ret; guard(mutex)(&st->lock); ret = __axi_dac_frequency_set(st, chan->channel, st->dac_clk, freq, tone_2); if (ret) return ret; return len; } static int axi_dac_scale_set(struct axi_dac_state *st, const struct iio_chan_spec *chan, const char *buf, size_t len, unsigned int tone_2) { int integer, frac, scale; u32 raw = 0, reg; int ret; ret = iio_str_to_fixpoint(buf, 100000, &integer, &frac); if (ret) return ret; scale = integer * MEGA + frac; if (scale <= -2 * (int)MEGA || scale >= 2 * (int)MEGA) return -EINVAL; /* format is 1.1.14 (sign, integer and fractional bits) */ if (scale < 0) { raw = FIELD_PREP(AXI_DAC_SCALE_SIGN, 1); scale *= -1; } raw |= div_u64((u64)scale * AXI_DAC_SCALE_INT, MEGA); if (tone_2) reg = AXI_DAC_REG_CHAN_CNTRL_3(chan->channel); else reg = AXI_DAC_REG_CHAN_CNTRL_1(chan->channel); guard(mutex)(&st->lock); ret = regmap_write(st->regmap, reg, raw); if (ret) return ret; /* synchronize channels */ ret = regmap_set_bits(st->regmap, AXI_DAC_REG_CNTRL_1, AXI_DAC_SYNC); if (ret) return ret; return len; } static int axi_dac_phase_set(struct axi_dac_state *st, const struct iio_chan_spec *chan, const char *buf, size_t len, unsigned int tone_2) { int integer, frac, phase; u32 raw, reg; int ret; ret = iio_str_to_fixpoint(buf, 100000, &integer, &frac); if (ret) return ret; phase = integer * MEGA + frac; if (phase < 0 || phase > AXI_DAC_2_PI_MEGA) return -EINVAL; raw = DIV_ROUND_CLOSEST_ULL((u64)phase * U16_MAX, AXI_DAC_2_PI_MEGA); if (tone_2) reg = AXI_DAC_REG_CHAN_CNTRL_4(chan->channel); else reg = AXI_DAC_REG_CHAN_CNTRL_2(chan->channel); guard(mutex)(&st->lock); ret = regmap_update_bits(st->regmap, reg, AXI_DAC_PHASE, FIELD_PREP(AXI_DAC_PHASE, raw)); if (ret) return ret; /* synchronize channels */ ret = regmap_set_bits(st->regmap, AXI_DAC_REG_CNTRL_1, AXI_DAC_SYNC); if (ret) return ret; return len; } static int axi_dac_ext_info_set(struct iio_backend *back, uintptr_t private, const struct iio_chan_spec *chan, const char *buf, size_t len) { struct axi_dac_state *st = iio_backend_get_priv(back); switch (private) { case AXI_DAC_FREQ_TONE_1: case AXI_DAC_FREQ_TONE_2: return axi_dac_frequency_set(st, chan, buf, len, private == AXI_DAC_FREQ_TONE_2); case AXI_DAC_SCALE_TONE_1: case AXI_DAC_SCALE_TONE_2: return axi_dac_scale_set(st, chan, buf, len, private == AXI_DAC_SCALE_TONE_2); case AXI_DAC_PHASE_TONE_1: case AXI_DAC_PHASE_TONE_2: return axi_dac_phase_set(st, chan, buf, len, private == AXI_DAC_PHASE_TONE_2); default: return -EOPNOTSUPP; } } static int axi_dac_ext_info_get(struct iio_backend *back, uintptr_t private, const struct iio_chan_spec *chan, char *buf) { struct axi_dac_state *st = iio_backend_get_priv(back); switch (private) { case AXI_DAC_FREQ_TONE_1: case AXI_DAC_FREQ_TONE_2: return axi_dac_frequency_get(st, chan, buf, private - AXI_DAC_FREQ_TONE_1); case AXI_DAC_SCALE_TONE_1: case AXI_DAC_SCALE_TONE_2: return axi_dac_scale_get(st, chan, buf, private - AXI_DAC_SCALE_TONE_1); case AXI_DAC_PHASE_TONE_1: case AXI_DAC_PHASE_TONE_2: return axi_dac_phase_get(st, chan, buf, private - AXI_DAC_PHASE_TONE_1); default: return -EOPNOTSUPP; } } static const struct iio_chan_spec_ext_info axi_dac_ext_info[] = { IIO_BACKEND_EX_INFO("frequency0", IIO_SEPARATE, AXI_DAC_FREQ_TONE_1), IIO_BACKEND_EX_INFO("frequency1", IIO_SEPARATE, AXI_DAC_FREQ_TONE_2), IIO_BACKEND_EX_INFO("scale0", IIO_SEPARATE, AXI_DAC_SCALE_TONE_1), IIO_BACKEND_EX_INFO("scale1", IIO_SEPARATE, AXI_DAC_SCALE_TONE_2), IIO_BACKEND_EX_INFO("phase0", IIO_SEPARATE, AXI_DAC_PHASE_TONE_1), IIO_BACKEND_EX_INFO("phase1", IIO_SEPARATE, AXI_DAC_PHASE_TONE_2), {} }; static int axi_dac_extend_chan(struct iio_backend *back, struct iio_chan_spec *chan) { struct axi_dac_state *st = iio_backend_get_priv(back); if (chan->type != IIO_ALTVOLTAGE) return -EINVAL; if (st->reg_config & AXI_DDS_DISABLE) /* nothing to extend */ return 0; chan->ext_info = axi_dac_ext_info; return 0; } static int axi_dac_data_source_set(struct iio_backend *back, unsigned int chan, enum iio_backend_data_source data) { struct axi_dac_state *st = iio_backend_get_priv(back); switch (data) { case IIO_BACKEND_INTERNAL_CONTINUOUS_WAVE: return regmap_update_bits(st->regmap, AXI_DAC_REG_CHAN_CNTRL_7(chan), AXI_DAC_DATA_SEL, AXI_DAC_DATA_INTERNAL_TONE); case IIO_BACKEND_EXTERNAL: return regmap_update_bits(st->regmap, AXI_DAC_REG_CHAN_CNTRL_7(chan), AXI_DAC_DATA_SEL, AXI_DAC_DATA_DMA); default: return -EINVAL; } } static int axi_dac_set_sample_rate(struct iio_backend *back, unsigned int chan, u64 sample_rate) { struct axi_dac_state *st = iio_backend_get_priv(back); unsigned int freq; int ret, tone; if (!sample_rate) return -EINVAL; if (st->reg_config & AXI_DDS_DISABLE) /* sample_rate has no meaning if DDS is disabled */ return 0; guard(mutex)(&st->lock); /* * If dac_clk is 0 then this must be the first time we're being notified * about the interface sample rate. Hence, just update our internal * variable and bail... If it's not 0, then we get the current DDS * frequency (for the old rate) and update the registers for the new * sample rate. */ if (!st->dac_clk) { st->dac_clk = sample_rate; return 0; } for (tone = 0; tone <= AXI_DAC_FREQ_TONE_2; tone++) { ret = __axi_dac_frequency_get(st, chan, tone, &freq); if (ret) return ret; ret = __axi_dac_frequency_set(st, chan, sample_rate, tone, freq); if (ret) return ret; } st->dac_clk = sample_rate; return 0; } static int axi_dac_reg_access(struct iio_backend *back, unsigned int reg, unsigned int writeval, unsigned int *readval) { struct axi_dac_state *st = iio_backend_get_priv(back); if (readval) return regmap_read(st->regmap, reg, readval); return regmap_write(st->regmap, reg, writeval); } static const struct iio_backend_ops axi_dac_generic_ops = { .enable = axi_dac_enable, .disable = axi_dac_disable, .request_buffer = axi_dac_request_buffer, .free_buffer = axi_dac_free_buffer, .extend_chan_spec = axi_dac_extend_chan, .ext_info_set = axi_dac_ext_info_set, .ext_info_get = axi_dac_ext_info_get, .data_source_set = axi_dac_data_source_set, .set_sample_rate = axi_dac_set_sample_rate, .debugfs_reg_access = iio_backend_debugfs_ptr(axi_dac_reg_access), }; static const struct iio_backend_info axi_dac_generic = { .name = "axi-dac", .ops = &axi_dac_generic_ops, }; static const struct regmap_config axi_dac_regmap_config = { .val_bits = 32, .reg_bits = 32, .reg_stride = 4, .max_register = 0x0800, }; static int axi_dac_probe(struct platform_device *pdev) { const unsigned int *expected_ver; struct axi_dac_state *st; void __iomem *base; unsigned int ver; struct clk *clk; int ret; st = devm_kzalloc(&pdev->dev, sizeof(*st), GFP_KERNEL); if (!st) return -ENOMEM; expected_ver = device_get_match_data(&pdev->dev); if (!expected_ver) return -ENODEV; clk = devm_clk_get_enabled(&pdev->dev, NULL); if (IS_ERR(clk)) return dev_err_probe(&pdev->dev, PTR_ERR(clk), "failed to get clock\n"); base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(base)) return PTR_ERR(base); st->dev = &pdev->dev; st->regmap = devm_regmap_init_mmio(&pdev->dev, base, &axi_dac_regmap_config); if (IS_ERR(st->regmap)) return dev_err_probe(&pdev->dev, PTR_ERR(st->regmap), "failed to init register map\n"); /* * Force disable the core. Up to the frontend to enable us. And we can * still read/write registers... */ ret = regmap_write(st->regmap, AXI_DAC_REG_RSTN, 0); if (ret) return ret; ret = regmap_read(st->regmap, ADI_AXI_REG_VERSION, &ver); if (ret) return ret; if (ADI_AXI_PCORE_VER_MAJOR(ver) != ADI_AXI_PCORE_VER_MAJOR(*expected_ver)) { dev_err(&pdev->dev, "Major version mismatch. Expected %d.%.2d.%c, Reported %d.%.2d.%c\n", ADI_AXI_PCORE_VER_MAJOR(*expected_ver), ADI_AXI_PCORE_VER_MINOR(*expected_ver), ADI_AXI_PCORE_VER_PATCH(*expected_ver), ADI_AXI_PCORE_VER_MAJOR(ver), ADI_AXI_PCORE_VER_MINOR(ver), ADI_AXI_PCORE_VER_PATCH(ver)); return -ENODEV; } /* Let's get the core read only configuration */ ret = regmap_read(st->regmap, AXI_DAC_REG_CONFIG, &st->reg_config); if (ret) return ret; /* * In some designs, setting the R1_MODE bit to 0 (which is the default * value) causes all channels of the frontend to be routed to the same * DMA (so they are sampled together). This is for things like * Multiple-Input and Multiple-Output (MIMO). As most of the times we * want independent channels let's override the core's default value and * set the R1_MODE bit. */ ret = regmap_set_bits(st->regmap, AXI_DAC_REG_CNTRL_2, ADI_DAC_R1_MODE); if (ret) return ret; mutex_init(&st->lock); ret = devm_iio_backend_register(&pdev->dev, &axi_dac_generic, st); if (ret) return dev_err_probe(&pdev->dev, ret, "failed to register iio backend\n"); dev_info(&pdev->dev, "AXI DAC IP core (%d.%.2d.%c) probed\n", ADI_AXI_PCORE_VER_MAJOR(ver), ADI_AXI_PCORE_VER_MINOR(ver), ADI_AXI_PCORE_VER_PATCH(ver)); return 0; } static unsigned int axi_dac_9_1_b_info = ADI_AXI_PCORE_VER(9, 1, 'b'); static const struct of_device_id axi_dac_of_match[] = { { .compatible = "adi,axi-dac-9.1.b", .data = &axi_dac_9_1_b_info }, {} }; MODULE_DEVICE_TABLE(of, axi_dac_of_match); static struct platform_driver axi_dac_driver = { .driver = { .name = "adi-axi-dac", .of_match_table = axi_dac_of_match, }, .probe = axi_dac_probe, }; module_platform_driver(axi_dac_driver); MODULE_AUTHOR("Nuno Sa "); MODULE_DESCRIPTION("Analog Devices Generic AXI DAC IP core driver"); MODULE_LICENSE("GPL"); MODULE_IMPORT_NS(IIO_DMAENGINE_BUFFER); MODULE_IMPORT_NS(IIO_BACKEND);