diff options
Diffstat (limited to 'sound/soc/loongson/loongson_dma.c')
| -rw-r--r-- | sound/soc/loongson/loongson_dma.c | 350 |
1 files changed, 350 insertions, 0 deletions
diff --git a/sound/soc/loongson/loongson_dma.c b/sound/soc/loongson/loongson_dma.c new file mode 100644 index 0000000000..65b6719e61 --- /dev/null +++ b/sound/soc/loongson/loongson_dma.c @@ -0,0 +1,350 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Loongson ALSA SoC Platform (DMA) driver +// +// Copyright (C) 2023 Loongson Technology Corporation Limited +// Author: Yingkun Meng <mengyingkun@loongson.cn> +// + +#include <linux/module.h> +#include <linux/io-64-nonatomic-lo-hi.h> +#include <linux/delay.h> +#include <linux/pm_runtime.h> +#include <linux/dma-mapping.h> +#include <sound/soc.h> +#include <sound/pcm.h> +#include <sound/pcm_params.h> +#include "loongson_i2s.h" + +/* DMA dma_order Register */ +#define DMA_ORDER_STOP (1 << 4) /* DMA stop */ +#define DMA_ORDER_START (1 << 3) /* DMA start */ +#define DMA_ORDER_ASK_VALID (1 << 2) /* DMA ask valid flag */ +#define DMA_ORDER_AXI_UNCO (1 << 1) /* Uncache access */ +#define DMA_ORDER_ADDR_64 (1 << 0) /* 64bits address support */ + +#define DMA_ORDER_ASK_MASK (~0x1fUL) /* Ask addr mask */ +#define DMA_ORDER_CTRL_MASK (0x0fUL) /* Control mask */ + +/* + * DMA registers descriptor. + */ +struct loongson_dma_desc { + u32 order; /* Next descriptor address register */ + u32 saddr; /* Source address register */ + u32 daddr; /* Device address register */ + u32 length; /* Total length register */ + u32 step_length; /* Memory stride register */ + u32 step_times; /* Repeat time register */ + u32 cmd; /* Command register */ + u32 stats; /* Status register */ + u32 order_hi; /* Next descriptor high address register */ + u32 saddr_hi; /* High source address register */ + u32 res[6]; /* Reserved */ +} __packed; + +struct loongson_runtime_data { + struct loongson_dma_data *dma_data; + + struct loongson_dma_desc *dma_desc_arr; + dma_addr_t dma_desc_arr_phy; + int dma_desc_arr_size; + + struct loongson_dma_desc *dma_pos_desc; + dma_addr_t dma_pos_desc_phy; +}; + +static const struct snd_pcm_hardware ls_pcm_hardware = { + .info = SNDRV_PCM_INFO_MMAP | + SNDRV_PCM_INFO_INTERLEAVED | + SNDRV_PCM_INFO_MMAP_VALID | + SNDRV_PCM_INFO_RESUME | + SNDRV_PCM_INFO_PAUSE, + .formats = (SNDRV_PCM_FMTBIT_S8 | + SNDRV_PCM_FMTBIT_S16_LE | + SNDRV_PCM_FMTBIT_S20_3LE | + SNDRV_PCM_FMTBIT_S24_LE), + .period_bytes_min = 128, + .period_bytes_max = 128 * 1024, + .periods_min = 1, + .periods_max = PAGE_SIZE / sizeof(struct loongson_dma_desc), + .buffer_bytes_max = 1024 * 1024, +}; + +static struct +loongson_dma_desc *dma_desc_save(struct loongson_runtime_data *prtd) +{ + void __iomem *order_reg = prtd->dma_data->order_addr; + u64 val; + + val = (u64)prtd->dma_pos_desc_phy & DMA_ORDER_ASK_MASK; + val |= (readq(order_reg) & DMA_ORDER_CTRL_MASK); + val |= DMA_ORDER_ASK_VALID; + writeq(val, order_reg); + + while (readl(order_reg) & DMA_ORDER_ASK_VALID) + udelay(2); + + return prtd->dma_pos_desc; +} + +static int loongson_pcm_trigger(struct snd_soc_component *component, + struct snd_pcm_substream *substream, int cmd) +{ + struct loongson_runtime_data *prtd = substream->runtime->private_data; + struct device *dev = substream->pcm->card->dev; + void __iomem *order_reg = prtd->dma_data->order_addr; + u64 val; + int ret = 0; + + switch (cmd) { + case SNDRV_PCM_TRIGGER_START: + case SNDRV_PCM_TRIGGER_RESUME: + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: + val = prtd->dma_pos_desc_phy & DMA_ORDER_ASK_MASK; + if (dev->coherent_dma_mask == DMA_BIT_MASK(64)) + val |= DMA_ORDER_ADDR_64; + else + val &= ~DMA_ORDER_ADDR_64; + val |= (readq(order_reg) & DMA_ORDER_CTRL_MASK); + val |= DMA_ORDER_START; + writeq(val, order_reg); + + while ((readl(order_reg) & DMA_ORDER_START)) + udelay(2); + break; + case SNDRV_PCM_TRIGGER_STOP: + case SNDRV_PCM_TRIGGER_SUSPEND: + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: + dma_desc_save(prtd); + + /* dma stop */ + val = readq(order_reg) | DMA_ORDER_STOP; + writeq(val, order_reg); + udelay(1000); + + break; + default: + dev_err(dev, "Invalid pcm trigger operation\n"); + return -EINVAL; + } + + return ret; +} + +static int loongson_pcm_hw_params(struct snd_soc_component *component, + struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *params) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct device *dev = substream->pcm->card->dev; + struct loongson_runtime_data *prtd = runtime->private_data; + size_t buf_len = params_buffer_bytes(params); + size_t period_len = params_period_bytes(params); + dma_addr_t order_addr, mem_addr; + struct loongson_dma_desc *desc; + u32 num_periods; + int i; + + if (buf_len % period_len) { + dev_err(dev, "buf len not multiply of period len\n"); + return -EINVAL; + } + + num_periods = buf_len / period_len; + if (!num_periods || num_periods > prtd->dma_desc_arr_size) { + dev_err(dev, "dma data too small or too big\n"); + return -EINVAL; + } + + snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer); + runtime->dma_bytes = buf_len; + + /* initialize dma descriptor array */ + mem_addr = runtime->dma_addr; + order_addr = prtd->dma_desc_arr_phy; + for (i = 0; i < num_periods; i++) { + desc = &prtd->dma_desc_arr[i]; + + /* next descriptor physical address */ + order_addr += sizeof(*desc); + desc->order = lower_32_bits(order_addr | BIT(0)); + desc->order_hi = upper_32_bits(order_addr); + + desc->saddr = lower_32_bits(mem_addr); + desc->saddr_hi = upper_32_bits(mem_addr); + desc->daddr = prtd->dma_data->dev_addr; + + desc->cmd = BIT(0); + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) + desc->cmd |= BIT(12); + + desc->length = period_len >> 2; + desc->step_length = 0; + desc->step_times = 1; + + mem_addr += period_len; + } + desc = &prtd->dma_desc_arr[num_periods - 1]; + desc->order = lower_32_bits(prtd->dma_desc_arr_phy | BIT(0)); + desc->order_hi = upper_32_bits(prtd->dma_desc_arr_phy); + + /* init position descriptor */ + *prtd->dma_pos_desc = *prtd->dma_desc_arr; + + return 0; +} + +static snd_pcm_uframes_t +loongson_pcm_pointer(struct snd_soc_component *component, + struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct loongson_runtime_data *prtd = runtime->private_data; + struct loongson_dma_desc *desc; + snd_pcm_uframes_t x; + u64 addr; + + desc = dma_desc_save(prtd); + addr = ((u64)desc->saddr_hi << 32) | desc->saddr; + + x = bytes_to_frames(runtime, addr - runtime->dma_addr); + if (x == runtime->buffer_size) + x = 0; + return x; +} + +static irqreturn_t loongson_pcm_dma_irq(int irq, void *devid) +{ + struct snd_pcm_substream *substream = devid; + + snd_pcm_period_elapsed(substream); + return IRQ_HANDLED; +} + +static int loongson_pcm_open(struct snd_soc_component *component, + struct snd_pcm_substream *substream) +{ + struct snd_pcm_runtime *runtime = substream->runtime; + struct snd_soc_pcm_runtime *rtd = substream->private_data; + struct snd_card *card = substream->pcm->card; + struct loongson_runtime_data *prtd; + struct loongson_dma_data *dma_data; + int ret; + + /* + * For mysterious reasons (and despite what the manual says) + * playback samples are lost if the DMA count is not a multiple + * of the DMA burst size. Let's add a rule to enforce that. + */ + snd_pcm_hw_constraint_step(runtime, 0, + SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 128); + snd_pcm_hw_constraint_step(runtime, 0, + SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 128); + snd_pcm_hw_constraint_integer(substream->runtime, + SNDRV_PCM_HW_PARAM_PERIODS); + snd_soc_set_runtime_hwparams(substream, &ls_pcm_hardware); + + prtd = kzalloc(sizeof(*prtd), GFP_KERNEL); + if (!prtd) + return -ENOMEM; + + prtd->dma_desc_arr = dma_alloc_coherent(card->dev, PAGE_SIZE, + &prtd->dma_desc_arr_phy, + GFP_KERNEL); + if (!prtd->dma_desc_arr) { + ret = -ENOMEM; + goto desc_err; + } + prtd->dma_desc_arr_size = PAGE_SIZE / sizeof(*prtd->dma_desc_arr); + + prtd->dma_pos_desc = dma_alloc_coherent(card->dev, + sizeof(*prtd->dma_pos_desc), + &prtd->dma_pos_desc_phy, + GFP_KERNEL); + if (!prtd->dma_pos_desc) { + ret = -ENOMEM; + goto pos_err; + } + + dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream); + prtd->dma_data = dma_data; + + substream->runtime->private_data = prtd; + + return 0; +pos_err: + dma_free_coherent(card->dev, PAGE_SIZE, prtd->dma_desc_arr, + prtd->dma_desc_arr_phy); +desc_err: + kfree(prtd); + + return ret; +} + +static int loongson_pcm_close(struct snd_soc_component *component, + struct snd_pcm_substream *substream) +{ + struct snd_card *card = substream->pcm->card; + struct loongson_runtime_data *prtd = substream->runtime->private_data; + + dma_free_coherent(card->dev, PAGE_SIZE, prtd->dma_desc_arr, + prtd->dma_desc_arr_phy); + + dma_free_coherent(card->dev, sizeof(*prtd->dma_pos_desc), + prtd->dma_pos_desc, prtd->dma_pos_desc_phy); + + kfree(prtd); + return 0; +} + +static int loongson_pcm_mmap(struct snd_soc_component *component, + struct snd_pcm_substream *substream, + struct vm_area_struct *vma) +{ + return remap_pfn_range(vma, vma->vm_start, + substream->dma_buffer.addr >> PAGE_SHIFT, + vma->vm_end - vma->vm_start, vma->vm_page_prot); +} + +static int loongson_pcm_new(struct snd_soc_component *component, + struct snd_soc_pcm_runtime *rtd) +{ + struct snd_card *card = rtd->card->snd_card; + struct snd_pcm_substream *substream; + struct loongson_dma_data *dma_data; + unsigned int i; + int ret; + + for_each_pcm_streams(i) { + substream = rtd->pcm->streams[i].substream; + if (!substream) + continue; + + dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), + substream); + ret = devm_request_irq(card->dev, dma_data->irq, + loongson_pcm_dma_irq, + IRQF_TRIGGER_HIGH, LS_I2S_DRVNAME, + substream); + if (ret < 0) { + dev_err(card->dev, "request irq for DMA failed\n"); + return ret; + } + } + + return snd_pcm_set_fixed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV, + card->dev, + ls_pcm_hardware.buffer_bytes_max); +} + +const struct snd_soc_component_driver loongson_i2s_component = { + .name = LS_I2S_DRVNAME, + .open = loongson_pcm_open, + .close = loongson_pcm_close, + .hw_params = loongson_pcm_hw_params, + .trigger = loongson_pcm_trigger, + .pointer = loongson_pcm_pointer, + .mmap = loongson_pcm_mmap, + .pcm_construct = loongson_pcm_new, +}; |