diff options
Diffstat (limited to 'drivers/dma/img-mdc-dma.c')
| -rw-r--r-- | drivers/dma/img-mdc-dma.c | 1011 |
1 files changed, 1011 insertions, 0 deletions
diff --git a/drivers/dma/img-mdc-dma.c b/drivers/dma/img-mdc-dma.c new file mode 100644 index 000000000000..ed045a9ad634 --- /dev/null +++ b/drivers/dma/img-mdc-dma.c @@ -0,0 +1,1011 @@ +/* + * IMG Multi-threaded DMA Controller (MDC) + * + * Copyright (C) 2009,2012,2013 Imagination Technologies Ltd. + * Copyright (C) 2014 Google, Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + */ + +#include <linux/clk.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/dmapool.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_dma.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +#include "dmaengine.h" +#include "virt-dma.h" + +#define MDC_MAX_DMA_CHANNELS 32 + +#define MDC_GENERAL_CONFIG 0x000 +#define MDC_GENERAL_CONFIG_LIST_IEN BIT(31) +#define MDC_GENERAL_CONFIG_IEN BIT(29) +#define MDC_GENERAL_CONFIG_LEVEL_INT BIT(28) +#define MDC_GENERAL_CONFIG_INC_W BIT(12) +#define MDC_GENERAL_CONFIG_INC_R BIT(8) +#define MDC_GENERAL_CONFIG_PHYSICAL_W BIT(7) +#define MDC_GENERAL_CONFIG_WIDTH_W_SHIFT 4 +#define MDC_GENERAL_CONFIG_WIDTH_W_MASK 0x7 +#define MDC_GENERAL_CONFIG_PHYSICAL_R BIT(3) +#define MDC_GENERAL_CONFIG_WIDTH_R_SHIFT 0 +#define MDC_GENERAL_CONFIG_WIDTH_R_MASK 0x7 + +#define MDC_READ_PORT_CONFIG 0x004 +#define MDC_READ_PORT_CONFIG_STHREAD_SHIFT 28 +#define MDC_READ_PORT_CONFIG_STHREAD_MASK 0xf +#define MDC_READ_PORT_CONFIG_RTHREAD_SHIFT 24 +#define MDC_READ_PORT_CONFIG_RTHREAD_MASK 0xf +#define MDC_READ_PORT_CONFIG_WTHREAD_SHIFT 16 +#define MDC_READ_PORT_CONFIG_WTHREAD_MASK 0xf +#define MDC_READ_PORT_CONFIG_BURST_SIZE_SHIFT 4 +#define MDC_READ_PORT_CONFIG_BURST_SIZE_MASK 0xff +#define MDC_READ_PORT_CONFIG_DREQ_ENABLE BIT(1) + +#define MDC_READ_ADDRESS 0x008 + +#define MDC_WRITE_ADDRESS 0x00c + +#define MDC_TRANSFER_SIZE 0x010 +#define MDC_TRANSFER_SIZE_MASK 0xffffff + +#define MDC_LIST_NODE_ADDRESS 0x014 + +#define MDC_CMDS_PROCESSED 0x018 +#define MDC_CMDS_PROCESSED_CMDS_PROCESSED_SHIFT 16 +#define MDC_CMDS_PROCESSED_CMDS_PROCESSED_MASK 0x3f +#define MDC_CMDS_PROCESSED_INT_ACTIVE BIT(8) +#define MDC_CMDS_PROCESSED_CMDS_DONE_SHIFT 0 +#define MDC_CMDS_PROCESSED_CMDS_DONE_MASK 0x3f + +#define MDC_CONTROL_AND_STATUS 0x01c +#define MDC_CONTROL_AND_STATUS_CANCEL BIT(20) +#define MDC_CONTROL_AND_STATUS_LIST_EN BIT(4) +#define MDC_CONTROL_AND_STATUS_EN BIT(0) + +#define MDC_ACTIVE_TRANSFER_SIZE 0x030 + +#define MDC_GLOBAL_CONFIG_A 0x900 +#define MDC_GLOBAL_CONFIG_A_THREAD_ID_WIDTH_SHIFT 16 +#define MDC_GLOBAL_CONFIG_A_THREAD_ID_WIDTH_MASK 0xff +#define MDC_GLOBAL_CONFIG_A_DMA_CONTEXTS_SHIFT 8 +#define MDC_GLOBAL_CONFIG_A_DMA_CONTEXTS_MASK 0xff +#define MDC_GLOBAL_CONFIG_A_SYS_DAT_WIDTH_SHIFT 0 +#define MDC_GLOBAL_CONFIG_A_SYS_DAT_WIDTH_MASK 0xff + +struct mdc_hw_list_desc { + u32 gen_conf; + u32 readport_conf; + u32 read_addr; + u32 write_addr; + u32 xfer_size; + u32 node_addr; + u32 cmds_done; + u32 ctrl_status; + /* + * Not part of the list descriptor, but instead used by the CPU to + * traverse the list. + */ + struct mdc_hw_list_desc *next_desc; +}; + +struct mdc_tx_desc { + struct mdc_chan *chan; + struct virt_dma_desc vd; + dma_addr_t list_phys; + struct mdc_hw_list_desc *list; + bool cyclic; + bool cmd_loaded; + unsigned int list_len; + unsigned int list_period_len; + size_t list_xfer_size; + unsigned int list_cmds_done; +}; + +struct mdc_chan { + struct mdc_dma *mdma; + struct virt_dma_chan vc; + struct dma_slave_config config; + struct mdc_tx_desc *desc; + int irq; + unsigned int periph; + unsigned int thread; + unsigned int chan_nr; +}; + +struct mdc_dma_soc_data { + void (*enable_chan)(struct mdc_chan *mchan); + void (*disable_chan)(struct mdc_chan *mchan); +}; + +struct mdc_dma { + struct dma_device dma_dev; + void __iomem *regs; + struct clk *clk; + struct dma_pool *desc_pool; + struct regmap *periph_regs; + spinlock_t lock; + unsigned int nr_threads; + unsigned int nr_channels; + unsigned int bus_width; + unsigned int max_burst_mult; + unsigned int max_xfer_size; + const struct mdc_dma_soc_data *soc; + struct mdc_chan channels[MDC_MAX_DMA_CHANNELS]; +}; + +static inline u32 mdc_readl(struct mdc_dma *mdma, u32 reg) +{ + return readl(mdma->regs + reg); +} + +static inline void mdc_writel(struct mdc_dma *mdma, u32 val, u32 reg) +{ + writel(val, mdma->regs + reg); +} + +static inline u32 mdc_chan_readl(struct mdc_chan *mchan, u32 reg) +{ + return mdc_readl(mchan->mdma, mchan->chan_nr * 0x040 + reg); +} + +static inline void mdc_chan_writel(struct mdc_chan *mchan, u32 val, u32 reg) +{ + mdc_writel(mchan->mdma, val, mchan->chan_nr * 0x040 + reg); +} + +static inline struct mdc_chan *to_mdc_chan(struct dma_chan *c) +{ + return container_of(to_virt_chan(c), struct mdc_chan, vc); +} + +static inline struct mdc_tx_desc *to_mdc_desc(struct dma_async_tx_descriptor *t) +{ + struct virt_dma_desc *vdesc = container_of(t, struct virt_dma_desc, tx); + + return container_of(vdesc, struct mdc_tx_desc, vd); +} + +static inline struct device *mdma2dev(struct mdc_dma *mdma) +{ + return mdma->dma_dev.dev; +} + +static inline unsigned int to_mdc_width(unsigned int bytes) +{ + return ffs(bytes) - 1; +} + +static inline void mdc_set_read_width(struct mdc_hw_list_desc *ldesc, + unsigned int bytes) +{ + ldesc->gen_conf |= to_mdc_width(bytes) << + MDC_GENERAL_CONFIG_WIDTH_R_SHIFT; +} + +static inline void mdc_set_write_width(struct mdc_hw_list_desc *ldesc, + unsigned int bytes) +{ + ldesc->gen_conf |= to_mdc_width(bytes) << + MDC_GENERAL_CONFIG_WIDTH_W_SHIFT; +} + +static void mdc_list_desc_config(struct mdc_chan *mchan, + struct mdc_hw_list_desc *ldesc, + enum dma_transfer_direction dir, + dma_addr_t src, dma_addr_t dst, size_t len) +{ + struct mdc_dma *mdma = mchan->mdma; + unsigned int max_burst, burst_size; + + ldesc->gen_conf = MDC_GENERAL_CONFIG_IEN | MDC_GENERAL_CONFIG_LIST_IEN | + MDC_GENERAL_CONFIG_LEVEL_INT | MDC_GENERAL_CONFIG_PHYSICAL_W | + MDC_GENERAL_CONFIG_PHYSICAL_R; + ldesc->readport_conf = + (mchan->thread << MDC_READ_PORT_CONFIG_STHREAD_SHIFT) | + (mchan->thread << MDC_READ_PORT_CONFIG_RTHREAD_SHIFT) | + (mchan->thread << MDC_READ_PORT_CONFIG_WTHREAD_SHIFT); + ldesc->read_addr = src; + ldesc->write_addr = dst; + ldesc->xfer_size = len - 1; + ldesc->node_addr = 0; + ldesc->cmds_done = 0; + ldesc->ctrl_status = MDC_CONTROL_AND_STATUS_LIST_EN | + MDC_CONTROL_AND_STATUS_EN; + ldesc->next_desc = NULL; + + if (IS_ALIGNED(dst, mdma->bus_width) && + IS_ALIGNED(src, mdma->bus_width)) + max_burst = mdma->bus_width * mdma->max_burst_mult; + else + max_burst = mdma->bus_width * (mdma->max_burst_mult - 1); + + if (dir == DMA_MEM_TO_DEV) { + ldesc->gen_conf |= MDC_GENERAL_CONFIG_INC_R; + ldesc->readport_conf |= MDC_READ_PORT_CONFIG_DREQ_ENABLE; + mdc_set_read_width(ldesc, mdma->bus_width); + mdc_set_write_width(ldesc, mchan->config.dst_addr_width); + burst_size = min(max_burst, mchan->config.dst_maxburst * + mchan->config.dst_addr_width); + } else if (dir == DMA_DEV_TO_MEM) { + ldesc->gen_conf |= MDC_GENERAL_CONFIG_INC_W; + ldesc->readport_conf |= MDC_READ_PORT_CONFIG_DREQ_ENABLE; + mdc_set_read_width(ldesc, mchan->config.src_addr_width); + mdc_set_write_width(ldesc, mdma->bus_width); + burst_size = min(max_burst, mchan->config.src_maxburst * + mchan->config.src_addr_width); + } else { + ldesc->gen_conf |= MDC_GENERAL_CONFIG_INC_R | + MDC_GENERAL_CONFIG_INC_W; + mdc_set_read_width(ldesc, mdma->bus_width); + mdc_set_write_width(ldesc, mdma->bus_width); + burst_size = max_burst; + } + ldesc->readport_conf |= (burst_size - 1) << + MDC_READ_PORT_CONFIG_BURST_SIZE_SHIFT; +} + +static void mdc_list_desc_free(struct mdc_tx_desc *mdesc) +{ + struct mdc_dma *mdma = mdesc->chan->mdma; + struct mdc_hw_list_desc *curr, *next; + dma_addr_t curr_phys, next_phys; + + curr = mdesc->list; + curr_phys = mdesc->list_phys; + while (curr) { + next = curr->next_desc; + next_phys = curr->node_addr; + dma_pool_free(mdma->desc_pool, curr, curr_phys); + curr = next; + curr_phys = next_phys; + } +} + +static void mdc_desc_free(struct virt_dma_desc *vd) +{ + struct mdc_tx_desc *mdesc = to_mdc_desc(&vd->tx); + + mdc_list_desc_free(mdesc); + kfree(mdesc); +} + +static struct dma_async_tx_descriptor *mdc_prep_dma_memcpy( + struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, + unsigned long flags) +{ + struct mdc_chan *mchan = to_mdc_chan(chan); + struct mdc_dma *mdma = mchan->mdma; + struct mdc_tx_desc *mdesc; + struct mdc_hw_list_desc *curr, *prev = NULL; + dma_addr_t curr_phys, prev_phys; + + if (!len) + return NULL; + + mdesc = kzalloc(sizeof(*mdesc), GFP_NOWAIT); + if (!mdesc) + return NULL; + mdesc->chan = mchan; + mdesc->list_xfer_size = len; + + while (len > 0) { + size_t xfer_size; + + curr = dma_pool_alloc(mdma->desc_pool, GFP_NOWAIT, &curr_phys); + if (!curr) + goto free_desc; + + if (prev) { + prev->node_addr = curr_phys; + prev->next_desc = curr; + } else { + mdesc->list_phys = curr_phys; + mdesc->list = curr; + } + + xfer_size = min_t(size_t, mdma->max_xfer_size, len); + + mdc_list_desc_config(mchan, curr, DMA_MEM_TO_MEM, src, dest, + xfer_size); + + prev = curr; + prev_phys = curr_phys; + + mdesc->list_len++; + src += xfer_size; + dest += xfer_size; + len -= xfer_size; + } + + return vchan_tx_prep(&mchan->vc, &mdesc->vd, flags); + +free_desc: + mdc_desc_free(&mdesc->vd); + + return NULL; +} + +static int mdc_check_slave_width(struct mdc_chan *mchan, + enum dma_transfer_direction dir) +{ + enum dma_slave_buswidth width; + + if (dir == DMA_MEM_TO_DEV) + width = mchan->config.dst_addr_width; + else + width = mchan->config.src_addr_width; + + switch (width) { + case DMA_SLAVE_BUSWIDTH_1_BYTE: + case DMA_SLAVE_BUSWIDTH_2_BYTES: + case DMA_SLAVE_BUSWIDTH_4_BYTES: + case DMA_SLAVE_BUSWIDTH_8_BYTES: + break; + default: + return -EINVAL; + } + + if (width > mchan->mdma->bus_width) + return -EINVAL; + + return 0; +} + +static struct dma_async_tx_descriptor *mdc_prep_dma_cyclic( + struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, + size_t period_len, enum dma_transfer_direction dir, + unsigned long flags) +{ + struct mdc_chan *mchan = to_mdc_chan(chan); + struct mdc_dma *mdma = mchan->mdma; + struct mdc_tx_desc *mdesc; + struct mdc_hw_list_desc *curr, *prev = NULL; + dma_addr_t curr_phys, prev_phys; + + if (!buf_len && !period_len) + return NULL; + + if (!is_slave_direction(dir)) + return NULL; + + if (mdc_check_slave_width(mchan, dir) < 0) + return NULL; + + mdesc = kzalloc(sizeof(*mdesc), GFP_NOWAIT); + if (!mdesc) + return NULL; + mdesc->chan = mchan; + mdesc->cyclic = true; + mdesc->list_xfer_size = buf_len; + mdesc->list_period_len = DIV_ROUND_UP(period_len, + mdma->max_xfer_size); + + while (buf_len > 0) { + size_t remainder = min(period_len, buf_len); + + while (remainder > 0) { + size_t xfer_size; + + curr = dma_pool_alloc(mdma->desc_pool, GFP_NOWAIT, + &curr_phys); + if (!curr) + goto free_desc; + + if (!prev) { + mdesc->list_phys = curr_phys; + mdesc->list = curr; + } else { + prev->node_addr = curr_phys; + prev->next_desc = curr; + } + + xfer_size = min_t(size_t, mdma->max_xfer_size, + remainder); + + if (dir == DMA_MEM_TO_DEV) { + mdc_list_desc_config(mchan, curr, dir, + buf_addr, + mchan->config.dst_addr, + xfer_size); + } else { + mdc_list_desc_config(mchan, curr, dir, + mchan->config.src_addr, + buf_addr, + xfer_size); + } + + prev = curr; + prev_phys = curr_phys; + + mdesc->list_len++; + buf_addr += xfer_size; + buf_len -= xfer_size; + remainder -= xfer_size; + } + } + prev->node_addr = mdesc->list_phys; + + return vchan_tx_prep(&mchan->vc, &mdesc->vd, flags); + +free_desc: + mdc_desc_free(&mdesc->vd); + + return NULL; +} + +static struct dma_async_tx_descriptor *mdc_prep_slave_sg( + struct dma_chan *chan, struct scatterlist *sgl, + unsigned int sg_len, enum dma_transfer_direction dir, + unsigned long flags, void *context) +{ + struct mdc_chan *mchan = to_mdc_chan(chan); + struct mdc_dma *mdma = mchan->mdma; + struct mdc_tx_desc *mdesc; + struct scatterlist *sg; + struct mdc_hw_list_desc *curr, *prev = NULL; + dma_addr_t curr_phys, prev_phys; + unsigned int i; + + if (!sgl) + return NULL; + + if (!is_slave_direction(dir)) + return NULL; + + if (mdc_check_slave_width(mchan, dir) < 0) + return NULL; + + mdesc = kzalloc(sizeof(*mdesc), GFP_NOWAIT); + if (!mdesc) + return NULL; + mdesc->chan = mchan; + + for_each_sg(sgl, sg, sg_len, i) { + dma_addr_t buf = sg_dma_address(sg); + size_t buf_len = sg_dma_len(sg); + + while (buf_len > 0) { + size_t xfer_size; + + curr = dma_pool_alloc(mdma->desc_pool, GFP_NOWAIT, + &curr_phys); + if (!curr) + goto free_desc; + + if (!prev) { + mdesc->list_phys = curr_phys; + mdesc->list = curr; + } else { + prev->node_addr = curr_phys; + prev->next_desc = curr; + } + + xfer_size = min_t(size_t, mdma->max_xfer_size, + buf_len); + + if (dir == DMA_MEM_TO_DEV) { + mdc_list_desc_config(mchan, curr, dir, buf, + mchan->config.dst_addr, + xfer_size); + } else { + mdc_list_desc_config(mchan, curr, dir, + mchan->config.src_addr, + buf, xfer_size); + } + + prev = curr; + prev_phys = curr_phys; + + mdesc->list_len++; + mdesc->list_xfer_size += xfer_size; + buf += xfer_size; + buf_len -= xfer_size; + } + } + + return vchan_tx_prep(&mchan->vc, &mdesc->vd, flags); + +free_desc: + mdc_desc_free(&mdesc->vd); + + return NULL; +} + +static void mdc_issue_desc(struct mdc_chan *mchan) +{ + struct mdc_dma *mdma = mchan->mdma; + struct virt_dma_desc *vd; + struct mdc_tx_desc *mdesc; + u32 val; + + vd = vchan_next_desc(&mchan->vc); + if (!vd) + return; + + list_del(&vd->node); + + mdesc = to_mdc_desc(&vd->tx); + mchan->desc = mdesc; + + dev_dbg(mdma2dev(mdma), "Issuing descriptor on channel %d\n", + mchan->chan_nr); + + mdma->soc->enable_chan(mchan); + + val = mdc_chan_readl(mchan, MDC_GENERAL_CONFIG); + val |= MDC_GENERAL_CONFIG_LIST_IEN | MDC_GENERAL_CONFIG_IEN | + MDC_GENERAL_CONFIG_LEVEL_INT | MDC_GENERAL_CONFIG_PHYSICAL_W | + MDC_GENERAL_CONFIG_PHYSICAL_R; + mdc_chan_writel(mchan, val, MDC_GENERAL_CONFIG); + val = (mchan->thread << MDC_READ_PORT_CONFIG_STHREAD_SHIFT) | + (mchan->thread << MDC_READ_PORT_CONFIG_RTHREAD_SHIFT) | + (mchan->thread << MDC_READ_PORT_CONFIG_WTHREAD_SHIFT); + mdc_chan_writel(mchan, val, MDC_READ_PORT_CONFIG); + mdc_chan_writel(mchan, mdesc->list_phys, MDC_LIST_NODE_ADDRESS); + val = mdc_chan_readl(mchan, MDC_CONTROL_AND_STATUS); + val |= MDC_CONTROL_AND_STATUS_LIST_EN; + mdc_chan_writel(mchan, val, MDC_CONTROL_AND_STATUS); +} + +static void mdc_issue_pending(struct dma_chan *chan) +{ + struct mdc_chan *mchan = to_mdc_chan(chan); + unsigned long flags; + + spin_lock_irqsave(&mchan->vc.lock, flags); + if (vchan_issue_pending(&mchan->vc) && !mchan->desc) + mdc_issue_desc(mchan); + spin_unlock_irqrestore(&mchan->vc.lock, flags); +} + +static enum dma_status mdc_tx_status(struct dma_chan *chan, + dma_cookie_t cookie, struct dma_tx_state *txstate) +{ + struct mdc_chan *mchan = to_mdc_chan(chan); + struct mdc_tx_desc *mdesc; + struct virt_dma_desc *vd; + unsigned long flags; + size_t bytes = 0; + int ret; + + ret = dma_cookie_status(chan, cookie, txstate); + if (ret == DMA_COMPLETE) + return ret; + + if (!txstate) + return ret; + + spin_lock_irqsave(&mchan->vc.lock, flags); + vd = vchan_find_desc(&mchan->vc, cookie); + if (vd) { + mdesc = to_mdc_desc(&vd->tx); + bytes = mdesc->list_xfer_size; + } else if (mchan->desc && mchan->desc->vd.tx.cookie == cookie) { + struct mdc_hw_list_desc *ldesc; + u32 val1, val2, done, processed, residue; + int i, cmds; + + mdesc = mchan->desc; + + /* + * Determine the number of commands that haven't been + * processed (handled by the IRQ handler) yet. + */ + do { + val1 = mdc_chan_readl(mchan, MDC_CMDS_PROCESSED) & + ~MDC_CMDS_PROCESSED_INT_ACTIVE; + residue = mdc_chan_readl(mchan, + MDC_ACTIVE_TRANSFER_SIZE); + val2 = mdc_chan_readl(mchan, MDC_CMDS_PROCESSED) & + ~MDC_CMDS_PROCESSED_INT_ACTIVE; + } while (val1 != val2); + + done = (val1 >> MDC_CMDS_PROCESSED_CMDS_DONE_SHIFT) & + MDC_CMDS_PROCESSED_CMDS_DONE_MASK; + processed = (val1 >> MDC_CMDS_PROCESSED_CMDS_PROCESSED_SHIFT) & + MDC_CMDS_PROCESSED_CMDS_PROCESSED_MASK; + cmds = (done - processed) % + (MDC_CMDS_PROCESSED_CMDS_DONE_MASK + 1); + + /* + * If the command loaded event hasn't been processed yet, then + * the difference above includes an extra command. + */ + if (!mdesc->cmd_loaded) + cmds--; + else + cmds += mdesc->list_cmds_done; + + bytes = mdesc->list_xfer_size; + ldesc = mdesc->list; + for (i = 0; i < cmds; i++) { + bytes -= ldesc->xfer_size + 1; + ldesc = ldesc->next_desc; + } + if (ldesc) { + if (residue != MDC_TRANSFER_SIZE_MASK) + bytes -= ldesc->xfer_size - residue; + else + bytes -= ldesc->xfer_size + 1; + } + } + spin_unlock_irqrestore(&mchan->vc.lock, flags); + + dma_set_residue(txstate, bytes); + + return ret; +} + +static int mdc_terminate_all(struct dma_chan *chan) +{ + struct mdc_chan *mchan = to_mdc_chan(chan); + struct mdc_tx_desc *mdesc; + unsigned long flags; + LIST_HEAD(head); + + spin_lock_irqsave(&mchan->vc.lock, flags); + + mdc_chan_writel(mchan, MDC_CONTROL_AND_STATUS_CANCEL, + MDC_CONTROL_AND_STATUS); + + mdesc = mchan->desc; + mchan->desc = NULL; + vchan_get_all_descriptors(&mchan->vc, &head); + + spin_unlock_irqrestore(&mchan->vc.lock, flags); + + if (mdesc) + mdc_desc_free(&mdesc->vd); + vchan_dma_desc_free_list(&mchan->vc, &head); + + return 0; +} + +static int mdc_slave_config(struct dma_chan *chan, + struct dma_slave_config *config) +{ + struct mdc_chan *mchan = to_mdc_chan(chan); + unsigned long flags; + + spin_lock_irqsave(&mchan->vc.lock, flags); + mchan->config = *config; + spin_unlock_irqrestore(&mchan->vc.lock, flags); + + return 0; +} + +static int mdc_alloc_chan_resources(struct dma_chan *chan) +{ + return 0; +} + +static void mdc_free_chan_resources(struct dma_chan *chan) +{ + struct mdc_chan *mchan = to_mdc_chan(chan); + struct mdc_dma *mdma = mchan->mdma; + + mdc_terminate_all(chan); + + mdma->soc->disable_chan(mchan); +} + +static irqreturn_t mdc_chan_irq(int irq, void *dev_id) +{ + struct mdc_chan *mchan = (struct mdc_chan *)dev_id; + struct mdc_tx_desc *mdesc; + u32 val, processed, done1, done2; + unsigned int i; + + spin_lock(&mchan->vc.lock); + + val = mdc_chan_readl(mchan, MDC_CMDS_PROCESSED); + processed = (val >> MDC_CMDS_PROCESSED_CMDS_PROCESSED_SHIFT) & + MDC_CMDS_PROCESSED_CMDS_PROCESSED_MASK; + /* + * CMDS_DONE may have incremented between reading CMDS_PROCESSED + * and clearing INT_ACTIVE. Re-read CMDS_PROCESSED to ensure we + * didn't miss a command completion. + */ + do { + val = mdc_chan_readl(mchan, MDC_CMDS_PROCESSED); + done1 = (val >> MDC_CMDS_PROCESSED_CMDS_DONE_SHIFT) & + MDC_CMDS_PROCESSED_CMDS_DONE_MASK; + val &= ~((MDC_CMDS_PROCESSED_CMDS_PROCESSED_MASK << + MDC_CMDS_PROCESSED_CMDS_PROCESSED_SHIFT) | + MDC_CMDS_PROCESSED_INT_ACTIVE); + val |= done1 << MDC_CMDS_PROCESSED_CMDS_PROCESSED_SHIFT; + mdc_chan_writel(mchan, val, MDC_CMDS_PROCESSED); + val = mdc_chan_readl(mchan, MDC_CMDS_PROCESSED); + done2 = (val >> MDC_CMDS_PROCESSED_CMDS_DONE_SHIFT) & + MDC_CMDS_PROCESSED_CMDS_DONE_MASK; + } while (done1 != done2); + + dev_dbg(mdma2dev(mchan->mdma), "IRQ on channel %d\n", mchan->chan_nr); + + mdesc = mchan->desc; + if (!mdesc) { + dev_warn(mdma2dev(mchan->mdma), + "IRQ with no active descriptor on channel %d\n", + mchan->chan_nr); + goto out; + } + + for (i = processed; i != done1; + i = (i + 1) % (MDC_CMDS_PROCESSED_CMDS_PROCESSED_MASK + 1)) { + /* + * The first interrupt in a transfer indicates that the + * command list has been loaded, not that a command has + * been completed. + */ + if (!mdesc->cmd_loaded) { + mdesc->cmd_loaded = true; + continue; + } + + mdesc->list_cmds_done++; + if (mdesc->cyclic) { + mdesc->list_cmds_done %= mdesc->list_len; + if (mdesc->list_cmds_done % mdesc->list_period_len == 0) + vchan_cyclic_callback(&mdesc->vd); + } else if (mdesc->list_cmds_done == mdesc->list_len) { + mchan->desc = NULL; + vchan_cookie_complete(&mdesc->vd); + mdc_issue_desc(mchan); + break; + } + } +out: + spin_unlock(&mchan->vc.lock); + + return IRQ_HANDLED; +} + +static struct dma_chan *mdc_of_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct mdc_dma *mdma = ofdma->of_dma_data; + struct dma_chan *chan; + + if (dma_spec->args_count != 3) + return NULL; + + list_for_each_entry(chan, &mdma->dma_dev.channels, device_node) { + struct mdc_chan *mchan = to_mdc_chan(chan); + + if (!(dma_spec->args[1] & BIT(mchan->chan_nr))) + continue; + if (dma_get_slave_channel(chan)) { + mchan->periph = dma_spec->args[0]; + mchan->thread = dma_spec->args[2]; + return chan; + } + } + + return NULL; +} + +#define PISTACHIO_CR_PERIPH_DMA_ROUTE(ch) (0x120 + 0x4 * ((ch) / 4)) +#define PISTACHIO_CR_PERIPH_DMA_ROUTE_SHIFT(ch) (8 * ((ch) % 4)) +#define PISTACHIO_CR_PERIPH_DMA_ROUTE_MASK 0x3f + +static void pistachio_mdc_enable_chan(struct mdc_chan *mchan) +{ + struct mdc_dma *mdma = mchan->mdma; + + regmap_update_bits(mdma->periph_regs, + PISTACHIO_CR_PERIPH_DMA_ROUTE(mchan->chan_nr), + PISTACHIO_CR_PERIPH_DMA_ROUTE_MASK << + PISTACHIO_CR_PERIPH_DMA_ROUTE_SHIFT(mchan->chan_nr), + mchan->periph << + PISTACHIO_CR_PERIPH_DMA_ROUTE_SHIFT(mchan->chan_nr)); +} + +static void pistachio_mdc_disable_chan(struct mdc_chan *mchan) +{ + struct mdc_dma *mdma = mchan->mdma; + + regmap_update_bits(mdma->periph_regs, + PISTACHIO_CR_PERIPH_DMA_ROUTE(mchan->chan_nr), + PISTACHIO_CR_PERIPH_DMA_ROUTE_MASK << + PISTACHIO_CR_PERIPH_DMA_ROUTE_SHIFT(mchan->chan_nr), + 0); +} + +static const struct mdc_dma_soc_data pistachio_mdc_data = { + .enable_chan = pistachio_mdc_enable_chan, + .disable_chan = pistachio_mdc_disable_chan, +}; + +static const struct of_device_id mdc_dma_of_match[] = { + { .compatible = "img,pistachio-mdc-dma", .data = &pistachio_mdc_data, }, + { }, +}; +MODULE_DEVICE_TABLE(of, mdc_dma_of_match); + +static int mdc_dma_probe(struct platform_device *pdev) +{ + struct mdc_dma *mdma; + struct resource *res; + const struct of_device_id *match; + unsigned int i; + u32 val; + int ret; + + mdma = devm_kzalloc(&pdev->dev, sizeof(*mdma), GFP_KERNEL); + if (!mdma) + return -ENOMEM; + platform_set_drvdata(pdev, mdma); + + match = of_match_device(mdc_dma_of_match, &pdev->dev); + mdma->soc = match->data; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + mdma->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(mdma->regs)) + return PTR_ERR(mdma->regs); + + mdma->periph_regs = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, + "img,cr-periph"); + if (IS_ERR(mdma->periph_regs)) + return PTR_ERR(mdma->periph_regs); + + mdma->clk = devm_clk_get(&pdev->dev, "sys"); + if (IS_ERR(mdma->clk)) + return PTR_ERR(mdma->clk); + + ret = clk_prepare_enable(mdma->clk); + if (ret) + return ret; + + dma_cap_zero(mdma->dma_dev.cap_mask); + dma_cap_set(DMA_SLAVE, mdma->dma_dev.cap_mask); + dma_cap_set(DMA_PRIVATE, mdma->dma_dev.cap_mask); + dma_cap_set(DMA_CYCLIC, mdma->dma_dev.cap_mask); + dma_cap_set(DMA_MEMCPY, mdma->dma_dev.cap_mask); + + val = mdc_readl(mdma, MDC_GLOBAL_CONFIG_A); + mdma->nr_channels = (val >> MDC_GLOBAL_CONFIG_A_DMA_CONTEXTS_SHIFT) & + MDC_GLOBAL_CONFIG_A_DMA_CONTEXTS_MASK; + mdma->nr_threads = + 1 << ((val >> MDC_GLOBAL_CONFIG_A_THREAD_ID_WIDTH_SHIFT) & + MDC_GLOBAL_CONFIG_A_THREAD_ID_WIDTH_MASK); + mdma->bus_width = + (1 << ((val >> MDC_GLOBAL_CONFIG_A_SYS_DAT_WIDTH_SHIFT) & + MDC_GLOBAL_CONFIG_A_SYS_DAT_WIDTH_MASK)) / 8; + /* + * Although transfer sizes of up to MDC_TRANSFER_SIZE_MASK + 1 bytes + * are supported, this makes it possible for the value reported in + * MDC_ACTIVE_TRANSFER_SIZE to be ambiguous - an active transfer size + * of MDC_TRANSFER_SIZE_MASK may indicate either that 0 bytes or + * MDC_TRANSFER_SIZE_MASK + 1 bytes are remaining. To eliminate this + * ambiguity, restrict transfer sizes to one bus-width less than the + * actual maximum. + */ + mdma->max_xfer_size = MDC_TRANSFER_SIZE_MASK + 1 - mdma->bus_width; + + of_property_read_u32(pdev->dev.of_node, "dma-channels", + &mdma->nr_channels); + ret = of_property_read_u32(pdev->dev.of_node, + "img,max-burst-multiplier", + &mdma->max_burst_mult); + if (ret) + goto disable_clk; + + mdma->dma_dev.dev = &pdev->dev; + mdma->dma_dev.device_prep_slave_sg = mdc_prep_slave_sg; + mdma->dma_dev.device_prep_dma_cyclic = mdc_prep_dma_cyclic; + mdma->dma_dev.device_prep_dma_memcpy = mdc_prep_dma_memcpy; + mdma->dma_dev.device_alloc_chan_resources = mdc_alloc_chan_resources; + mdma->dma_dev.device_free_chan_resources = mdc_free_chan_resources; + mdma->dma_dev.device_tx_status = mdc_tx_status; + mdma->dma_dev.device_issue_pending = mdc_issue_pending; + mdma->dma_dev.device_terminate_all = mdc_terminate_all; + mdma->dma_dev.device_config = mdc_slave_config; + + mdma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); + mdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; + for (i = 1; i <= mdma->bus_width; i <<= 1) { + mdma->dma_dev.src_addr_widths |= BIT(i); + mdma->dma_dev.dst_addr_widths |= BIT(i); + } + + INIT_LIST_HEAD(&mdma->dma_dev.channels); + for (i = 0; i < mdma->nr_channels; i++) { + struct mdc_chan *mchan = &mdma->channels[i]; + + mchan->mdma = mdma; + mchan->chan_nr = i; + mchan->irq = platform_get_irq(pdev, i); + if (mchan->irq < 0) { + ret = mchan->irq; + goto disable_clk; + } + ret = devm_request_irq(&pdev->dev, mchan->irq, mdc_chan_irq, + IRQ_TYPE_LEVEL_HIGH, + dev_name(&pdev->dev), mchan); + if (ret < 0) + goto disable_clk; + + mchan->vc.desc_free = mdc_desc_free; + vchan_init(&mchan->vc, &mdma->dma_dev); + } + + mdma->desc_pool = dmam_pool_create(dev_name(&pdev->dev), &pdev->dev, + sizeof(struct mdc_hw_list_desc), + 4, 0); + if (!mdma->desc_pool) { + ret = -ENOMEM; + goto disable_clk; + } + + ret = dma_async_device_register(&mdma->dma_dev); + if (ret) + goto disable_clk; + + ret = of_dma_controller_register(pdev->dev.of_node, mdc_of_xlate, mdma); + if (ret) + goto unregister; + + dev_info(&pdev->dev, "MDC with %u channels and %u threads\n", + mdma->nr_channels, mdma->nr_threads); + + return 0; + +unregister: + dma_async_device_unregister(&mdma->dma_dev); +disable_clk: + clk_disable_unprepare(mdma->clk); + return ret; +} + +static int mdc_dma_remove(struct platform_device *pdev) +{ + struct mdc_dma *mdma = platform_get_drvdata(pdev); + struct mdc_chan *mchan, *next; + + of_dma_controller_free(pdev->dev.of_node); + dma_async_device_unregister(&mdma->dma_dev); + + list_for_each_entry_safe(mchan, next, &mdma->dma_dev.channels, + vc.chan.device_node) { + list_del(&mchan->vc.chan.device_node); + + synchronize_irq(mchan->irq); + devm_free_irq(&pdev->dev, mchan->irq, mchan); + + tasklet_kill(&mchan->vc.task); + } + + clk_disable_unprepare(mdma->clk); + + return 0; +} + +static struct platform_driver mdc_dma_driver = { + .driver = { + .name = "img-mdc-dma", + .of_match_table = of_match_ptr(mdc_dma_of_match), + }, + .probe = mdc_dma_probe, + .remove = mdc_dma_remove, +}; +module_platform_driver(mdc_dma_driver); + +MODULE_DESCRIPTION("IMG Multi-threaded DMA Controller (MDC) driver"); +MODULE_AUTHOR("Andrew Bresticker <abrestic@chromium.org>"); +MODULE_LICENSE("GPL v2"); |