diff options
Diffstat (limited to 'drivers/dma/xilinx')
| -rw-r--r-- | drivers/dma/xilinx/Makefile | 1 | ||||
| -rw-r--r-- | drivers/dma/xilinx/xilinx_vdma.c | 1366 |
2 files changed, 1367 insertions, 0 deletions
diff --git a/drivers/dma/xilinx/Makefile b/drivers/dma/xilinx/Makefile new file mode 100644 index 000000000..3c4e9f2fe --- /dev/null +++ b/drivers/dma/xilinx/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_XILINX_VDMA) += xilinx_vdma.o diff --git a/drivers/dma/xilinx/xilinx_vdma.c b/drivers/dma/xilinx/xilinx_vdma.c new file mode 100644 index 000000000..d8434d465 --- /dev/null +++ b/drivers/dma/xilinx/xilinx_vdma.c @@ -0,0 +1,1366 @@ +/* + * DMA driver for Xilinx Video DMA Engine + * + * Copyright (C) 2010-2014 Xilinx, Inc. All rights reserved. + * + * Based on the Freescale DMA driver. + * + * Description: + * The AXI Video Direct Memory Access (AXI VDMA) core is a soft Xilinx IP + * core that provides high-bandwidth direct memory access between memory + * and AXI4-Stream type video target peripherals. The core provides efficient + * two dimensional DMA operations with independent asynchronous read (S2MM) + * and write (MM2S) channel operation. It can be configured to have either + * one channel or two channels. If configured as two channels, one is to + * transmit to the video device (MM2S) and another is to receive from the + * video device (S2MM). Initialization, status, interrupt and management + * registers are accessed through an AXI4-Lite slave interface. + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/bitops.h> +#include <linux/dmapool.h> +#include <linux/dma/xilinx_dma.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_dma.h> +#include <linux/of_platform.h> +#include <linux/of_irq.h> +#include <linux/slab.h> + +#include "../dmaengine.h" + +/* Register/Descriptor Offsets */ +#define XILINX_VDMA_MM2S_CTRL_OFFSET 0x0000 +#define XILINX_VDMA_S2MM_CTRL_OFFSET 0x0030 +#define XILINX_VDMA_MM2S_DESC_OFFSET 0x0050 +#define XILINX_VDMA_S2MM_DESC_OFFSET 0x00a0 + +/* Control Registers */ +#define XILINX_VDMA_REG_DMACR 0x0000 +#define XILINX_VDMA_DMACR_DELAY_MAX 0xff +#define XILINX_VDMA_DMACR_DELAY_SHIFT 24 +#define XILINX_VDMA_DMACR_FRAME_COUNT_MAX 0xff +#define XILINX_VDMA_DMACR_FRAME_COUNT_SHIFT 16 +#define XILINX_VDMA_DMACR_ERR_IRQ BIT(14) +#define XILINX_VDMA_DMACR_DLY_CNT_IRQ BIT(13) +#define XILINX_VDMA_DMACR_FRM_CNT_IRQ BIT(12) +#define XILINX_VDMA_DMACR_MASTER_SHIFT 8 +#define XILINX_VDMA_DMACR_FSYNCSRC_SHIFT 5 +#define XILINX_VDMA_DMACR_FRAMECNT_EN BIT(4) +#define XILINX_VDMA_DMACR_GENLOCK_EN BIT(3) +#define XILINX_VDMA_DMACR_RESET BIT(2) +#define XILINX_VDMA_DMACR_CIRC_EN BIT(1) +#define XILINX_VDMA_DMACR_RUNSTOP BIT(0) +#define XILINX_VDMA_DMACR_FSYNCSRC_MASK GENMASK(6, 5) + +#define XILINX_VDMA_REG_DMASR 0x0004 +#define XILINX_VDMA_DMASR_EOL_LATE_ERR BIT(15) +#define XILINX_VDMA_DMASR_ERR_IRQ BIT(14) +#define XILINX_VDMA_DMASR_DLY_CNT_IRQ BIT(13) +#define XILINX_VDMA_DMASR_FRM_CNT_IRQ BIT(12) +#define XILINX_VDMA_DMASR_SOF_LATE_ERR BIT(11) +#define XILINX_VDMA_DMASR_SG_DEC_ERR BIT(10) +#define XILINX_VDMA_DMASR_SG_SLV_ERR BIT(9) +#define XILINX_VDMA_DMASR_EOF_EARLY_ERR BIT(8) +#define XILINX_VDMA_DMASR_SOF_EARLY_ERR BIT(7) +#define XILINX_VDMA_DMASR_DMA_DEC_ERR BIT(6) +#define XILINX_VDMA_DMASR_DMA_SLAVE_ERR BIT(5) +#define XILINX_VDMA_DMASR_DMA_INT_ERR BIT(4) +#define XILINX_VDMA_DMASR_IDLE BIT(1) +#define XILINX_VDMA_DMASR_HALTED BIT(0) +#define XILINX_VDMA_DMASR_DELAY_MASK GENMASK(31, 24) +#define XILINX_VDMA_DMASR_FRAME_COUNT_MASK GENMASK(23, 16) + +#define XILINX_VDMA_REG_CURDESC 0x0008 +#define XILINX_VDMA_REG_TAILDESC 0x0010 +#define XILINX_VDMA_REG_REG_INDEX 0x0014 +#define XILINX_VDMA_REG_FRMSTORE 0x0018 +#define XILINX_VDMA_REG_THRESHOLD 0x001c +#define XILINX_VDMA_REG_FRMPTR_STS 0x0024 +#define XILINX_VDMA_REG_PARK_PTR 0x0028 +#define XILINX_VDMA_PARK_PTR_WR_REF_SHIFT 8 +#define XILINX_VDMA_PARK_PTR_RD_REF_SHIFT 0 +#define XILINX_VDMA_REG_VDMA_VERSION 0x002c + +/* Register Direct Mode Registers */ +#define XILINX_VDMA_REG_VSIZE 0x0000 +#define XILINX_VDMA_REG_HSIZE 0x0004 + +#define XILINX_VDMA_REG_FRMDLY_STRIDE 0x0008 +#define XILINX_VDMA_FRMDLY_STRIDE_FRMDLY_SHIFT 24 +#define XILINX_VDMA_FRMDLY_STRIDE_STRIDE_SHIFT 0 + +#define XILINX_VDMA_REG_START_ADDRESS(n) (0x000c + 4 * (n)) + +/* HW specific definitions */ +#define XILINX_VDMA_MAX_CHANS_PER_DEVICE 0x2 + +#define XILINX_VDMA_DMAXR_ALL_IRQ_MASK \ + (XILINX_VDMA_DMASR_FRM_CNT_IRQ | \ + XILINX_VDMA_DMASR_DLY_CNT_IRQ | \ + XILINX_VDMA_DMASR_ERR_IRQ) + +#define XILINX_VDMA_DMASR_ALL_ERR_MASK \ + (XILINX_VDMA_DMASR_EOL_LATE_ERR | \ + XILINX_VDMA_DMASR_SOF_LATE_ERR | \ + XILINX_VDMA_DMASR_SG_DEC_ERR | \ + XILINX_VDMA_DMASR_SG_SLV_ERR | \ + XILINX_VDMA_DMASR_EOF_EARLY_ERR | \ + XILINX_VDMA_DMASR_SOF_EARLY_ERR | \ + XILINX_VDMA_DMASR_DMA_DEC_ERR | \ + XILINX_VDMA_DMASR_DMA_SLAVE_ERR | \ + XILINX_VDMA_DMASR_DMA_INT_ERR) + +/* + * Recoverable errors are DMA Internal error, SOF Early, EOF Early + * and SOF Late. They are only recoverable when C_FLUSH_ON_FSYNC + * is enabled in the h/w system. + */ +#define XILINX_VDMA_DMASR_ERR_RECOVER_MASK \ + (XILINX_VDMA_DMASR_SOF_LATE_ERR | \ + XILINX_VDMA_DMASR_EOF_EARLY_ERR | \ + XILINX_VDMA_DMASR_SOF_EARLY_ERR | \ + XILINX_VDMA_DMASR_DMA_INT_ERR) + +/* Axi VDMA Flush on Fsync bits */ +#define XILINX_VDMA_FLUSH_S2MM 3 +#define XILINX_VDMA_FLUSH_MM2S 2 +#define XILINX_VDMA_FLUSH_BOTH 1 + +/* Delay loop counter to prevent hardware failure */ +#define XILINX_VDMA_LOOP_COUNT 1000000 + +/** + * struct xilinx_vdma_desc_hw - Hardware Descriptor + * @next_desc: Next Descriptor Pointer @0x00 + * @pad1: Reserved @0x04 + * @buf_addr: Buffer address @0x08 + * @pad2: Reserved @0x0C + * @vsize: Vertical Size @0x10 + * @hsize: Horizontal Size @0x14 + * @stride: Number of bytes between the first + * pixels of each horizontal line @0x18 + */ +struct xilinx_vdma_desc_hw { + u32 next_desc; + u32 pad1; + u32 buf_addr; + u32 pad2; + u32 vsize; + u32 hsize; + u32 stride; +} __aligned(64); + +/** + * struct xilinx_vdma_tx_segment - Descriptor segment + * @hw: Hardware descriptor + * @node: Node in the descriptor segments list + * @phys: Physical address of segment + */ +struct xilinx_vdma_tx_segment { + struct xilinx_vdma_desc_hw hw; + struct list_head node; + dma_addr_t phys; +} __aligned(64); + +/** + * struct xilinx_vdma_tx_descriptor - Per Transaction structure + * @async_tx: Async transaction descriptor + * @segments: TX segments list + * @node: Node in the channel descriptors list + */ +struct xilinx_vdma_tx_descriptor { + struct dma_async_tx_descriptor async_tx; + struct list_head segments; + struct list_head node; +}; + +/** + * struct xilinx_vdma_chan - Driver specific VDMA channel structure + * @xdev: Driver specific device structure + * @ctrl_offset: Control registers offset + * @desc_offset: TX descriptor registers offset + * @lock: Descriptor operation lock + * @pending_list: Descriptors waiting + * @active_desc: Active descriptor + * @allocated_desc: Allocated descriptor + * @done_list: Complete descriptors + * @common: DMA common channel + * @desc_pool: Descriptors pool + * @dev: The dma device + * @irq: Channel IRQ + * @id: Channel ID + * @direction: Transfer direction + * @num_frms: Number of frames + * @has_sg: Support scatter transfers + * @genlock: Support genlock mode + * @err: Channel has errors + * @tasklet: Cleanup work after irq + * @config: Device configuration info + * @flush_on_fsync: Flush on Frame sync + */ +struct xilinx_vdma_chan { + struct xilinx_vdma_device *xdev; + u32 ctrl_offset; + u32 desc_offset; + spinlock_t lock; + struct list_head pending_list; + struct xilinx_vdma_tx_descriptor *active_desc; + struct xilinx_vdma_tx_descriptor *allocated_desc; + struct list_head done_list; + struct dma_chan common; + struct dma_pool *desc_pool; + struct device *dev; + int irq; + int id; + enum dma_transfer_direction direction; + int num_frms; + bool has_sg; + bool genlock; + bool err; + struct tasklet_struct tasklet; + struct xilinx_vdma_config config; + bool flush_on_fsync; +}; + +/** + * struct xilinx_vdma_device - VDMA device structure + * @regs: I/O mapped base address + * @dev: Device Structure + * @common: DMA device structure + * @chan: Driver specific VDMA channel + * @has_sg: Specifies whether Scatter-Gather is present or not + * @flush_on_fsync: Flush on frame sync + */ +struct xilinx_vdma_device { + void __iomem *regs; + struct device *dev; + struct dma_device common; + struct xilinx_vdma_chan *chan[XILINX_VDMA_MAX_CHANS_PER_DEVICE]; + bool has_sg; + u32 flush_on_fsync; +}; + +/* Macros */ +#define to_xilinx_chan(chan) \ + container_of(chan, struct xilinx_vdma_chan, common) +#define to_vdma_tx_descriptor(tx) \ + container_of(tx, struct xilinx_vdma_tx_descriptor, async_tx) + +/* IO accessors */ +static inline u32 vdma_read(struct xilinx_vdma_chan *chan, u32 reg) +{ + return ioread32(chan->xdev->regs + reg); +} + +static inline void vdma_write(struct xilinx_vdma_chan *chan, u32 reg, u32 value) +{ + iowrite32(value, chan->xdev->regs + reg); +} + +static inline void vdma_desc_write(struct xilinx_vdma_chan *chan, u32 reg, + u32 value) +{ + vdma_write(chan, chan->desc_offset + reg, value); +} + +static inline u32 vdma_ctrl_read(struct xilinx_vdma_chan *chan, u32 reg) +{ + return vdma_read(chan, chan->ctrl_offset + reg); +} + +static inline void vdma_ctrl_write(struct xilinx_vdma_chan *chan, u32 reg, + u32 value) +{ + vdma_write(chan, chan->ctrl_offset + reg, value); +} + +static inline void vdma_ctrl_clr(struct xilinx_vdma_chan *chan, u32 reg, + u32 clr) +{ + vdma_ctrl_write(chan, reg, vdma_ctrl_read(chan, reg) & ~clr); +} + +static inline void vdma_ctrl_set(struct xilinx_vdma_chan *chan, u32 reg, + u32 set) +{ + vdma_ctrl_write(chan, reg, vdma_ctrl_read(chan, reg) | set); +} + +/* ----------------------------------------------------------------------------- + * Descriptors and segments alloc and free + */ + +/** + * xilinx_vdma_alloc_tx_segment - Allocate transaction segment + * @chan: Driver specific VDMA channel + * + * Return: The allocated segment on success and NULL on failure. + */ +static struct xilinx_vdma_tx_segment * +xilinx_vdma_alloc_tx_segment(struct xilinx_vdma_chan *chan) +{ + struct xilinx_vdma_tx_segment *segment; + dma_addr_t phys; + + segment = dma_pool_alloc(chan->desc_pool, GFP_ATOMIC, &phys); + if (!segment) + return NULL; + + memset(segment, 0, sizeof(*segment)); + segment->phys = phys; + + return segment; +} + +/** + * xilinx_vdma_free_tx_segment - Free transaction segment + * @chan: Driver specific VDMA channel + * @segment: VDMA transaction segment + */ +static void xilinx_vdma_free_tx_segment(struct xilinx_vdma_chan *chan, + struct xilinx_vdma_tx_segment *segment) +{ + dma_pool_free(chan->desc_pool, segment, segment->phys); +} + +/** + * xilinx_vdma_tx_descriptor - Allocate transaction descriptor + * @chan: Driver specific VDMA channel + * + * Return: The allocated descriptor on success and NULL on failure. + */ +static struct xilinx_vdma_tx_descriptor * +xilinx_vdma_alloc_tx_descriptor(struct xilinx_vdma_chan *chan) +{ + struct xilinx_vdma_tx_descriptor *desc; + unsigned long flags; + + if (chan->allocated_desc) + return chan->allocated_desc; + + desc = kzalloc(sizeof(*desc), GFP_KERNEL); + if (!desc) + return NULL; + + spin_lock_irqsave(&chan->lock, flags); + chan->allocated_desc = desc; + spin_unlock_irqrestore(&chan->lock, flags); + + INIT_LIST_HEAD(&desc->segments); + + return desc; +} + +/** + * xilinx_vdma_free_tx_descriptor - Free transaction descriptor + * @chan: Driver specific VDMA channel + * @desc: VDMA transaction descriptor + */ +static void +xilinx_vdma_free_tx_descriptor(struct xilinx_vdma_chan *chan, + struct xilinx_vdma_tx_descriptor *desc) +{ + struct xilinx_vdma_tx_segment *segment, *next; + + if (!desc) + return; + + list_for_each_entry_safe(segment, next, &desc->segments, node) { + list_del(&segment->node); + xilinx_vdma_free_tx_segment(chan, segment); + } + + kfree(desc); +} + +/* Required functions */ + +/** + * xilinx_vdma_free_desc_list - Free descriptors list + * @chan: Driver specific VDMA channel + * @list: List to parse and delete the descriptor + */ +static void xilinx_vdma_free_desc_list(struct xilinx_vdma_chan *chan, + struct list_head *list) +{ + struct xilinx_vdma_tx_descriptor *desc, *next; + + list_for_each_entry_safe(desc, next, list, node) { + list_del(&desc->node); + xilinx_vdma_free_tx_descriptor(chan, desc); + } +} + +/** + * xilinx_vdma_free_descriptors - Free channel descriptors + * @chan: Driver specific VDMA channel + */ +static void xilinx_vdma_free_descriptors(struct xilinx_vdma_chan *chan) +{ + unsigned long flags; + + spin_lock_irqsave(&chan->lock, flags); + + xilinx_vdma_free_desc_list(chan, &chan->pending_list); + xilinx_vdma_free_desc_list(chan, &chan->done_list); + + xilinx_vdma_free_tx_descriptor(chan, chan->active_desc); + chan->active_desc = NULL; + + spin_unlock_irqrestore(&chan->lock, flags); +} + +/** + * xilinx_vdma_free_chan_resources - Free channel resources + * @dchan: DMA channel + */ +static void xilinx_vdma_free_chan_resources(struct dma_chan *dchan) +{ + struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan); + + dev_dbg(chan->dev, "Free all channel resources.\n"); + + xilinx_vdma_free_descriptors(chan); + dma_pool_destroy(chan->desc_pool); + chan->desc_pool = NULL; +} + +/** + * xilinx_vdma_chan_desc_cleanup - Clean channel descriptors + * @chan: Driver specific VDMA channel + */ +static void xilinx_vdma_chan_desc_cleanup(struct xilinx_vdma_chan *chan) +{ + struct xilinx_vdma_tx_descriptor *desc, *next; + unsigned long flags; + + spin_lock_irqsave(&chan->lock, flags); + + list_for_each_entry_safe(desc, next, &chan->done_list, node) { + dma_async_tx_callback callback; + void *callback_param; + + /* Remove from the list of running transactions */ + list_del(&desc->node); + + /* Run the link descriptor callback function */ + callback = desc->async_tx.callback; + callback_param = desc->async_tx.callback_param; + if (callback) { + spin_unlock_irqrestore(&chan->lock, flags); + callback(callback_param); + spin_lock_irqsave(&chan->lock, flags); + } + + /* Run any dependencies, then free the descriptor */ + dma_run_dependencies(&desc->async_tx); + xilinx_vdma_free_tx_descriptor(chan, desc); + } + + spin_unlock_irqrestore(&chan->lock, flags); +} + +/** + * xilinx_vdma_do_tasklet - Schedule completion tasklet + * @data: Pointer to the Xilinx VDMA channel structure + */ +static void xilinx_vdma_do_tasklet(unsigned long data) +{ + struct xilinx_vdma_chan *chan = (struct xilinx_vdma_chan *)data; + + xilinx_vdma_chan_desc_cleanup(chan); +} + +/** + * xilinx_vdma_alloc_chan_resources - Allocate channel resources + * @dchan: DMA channel + * + * Return: '0' on success and failure value on error + */ +static int xilinx_vdma_alloc_chan_resources(struct dma_chan *dchan) +{ + struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan); + + /* Has this channel already been allocated? */ + if (chan->desc_pool) + return 0; + + /* + * We need the descriptor to be aligned to 64bytes + * for meeting Xilinx VDMA specification requirement. + */ + chan->desc_pool = dma_pool_create("xilinx_vdma_desc_pool", + chan->dev, + sizeof(struct xilinx_vdma_tx_segment), + __alignof__(struct xilinx_vdma_tx_segment), 0); + if (!chan->desc_pool) { + dev_err(chan->dev, + "unable to allocate channel %d descriptor pool\n", + chan->id); + return -ENOMEM; + } + + dma_cookie_init(dchan); + return 0; +} + +/** + * xilinx_vdma_tx_status - Get VDMA transaction status + * @dchan: DMA channel + * @cookie: Transaction identifier + * @txstate: Transaction state + * + * Return: DMA transaction status + */ +static enum dma_status xilinx_vdma_tx_status(struct dma_chan *dchan, + dma_cookie_t cookie, + struct dma_tx_state *txstate) +{ + return dma_cookie_status(dchan, cookie, txstate); +} + +/** + * xilinx_vdma_is_running - Check if VDMA channel is running + * @chan: Driver specific VDMA channel + * + * Return: '1' if running, '0' if not. + */ +static bool xilinx_vdma_is_running(struct xilinx_vdma_chan *chan) +{ + return !(vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) & + XILINX_VDMA_DMASR_HALTED) && + (vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) & + XILINX_VDMA_DMACR_RUNSTOP); +} + +/** + * xilinx_vdma_is_idle - Check if VDMA channel is idle + * @chan: Driver specific VDMA channel + * + * Return: '1' if idle, '0' if not. + */ +static bool xilinx_vdma_is_idle(struct xilinx_vdma_chan *chan) +{ + return vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) & + XILINX_VDMA_DMASR_IDLE; +} + +/** + * xilinx_vdma_halt - Halt VDMA channel + * @chan: Driver specific VDMA channel + */ +static void xilinx_vdma_halt(struct xilinx_vdma_chan *chan) +{ + int loop = XILINX_VDMA_LOOP_COUNT; + + vdma_ctrl_clr(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RUNSTOP); + + /* Wait for the hardware to halt */ + do { + if (vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) & + XILINX_VDMA_DMASR_HALTED) + break; + } while (loop--); + + if (!loop) { + dev_err(chan->dev, "Cannot stop channel %p: %x\n", + chan, vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR)); + chan->err = true; + } + + return; +} + +/** + * xilinx_vdma_start - Start VDMA channel + * @chan: Driver specific VDMA channel + */ +static void xilinx_vdma_start(struct xilinx_vdma_chan *chan) +{ + int loop = XILINX_VDMA_LOOP_COUNT; + + vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RUNSTOP); + + /* Wait for the hardware to start */ + do { + if (!(vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) & + XILINX_VDMA_DMASR_HALTED)) + break; + } while (loop--); + + if (!loop) { + dev_err(chan->dev, "Cannot start channel %p: %x\n", + chan, vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR)); + + chan->err = true; + } + + return; +} + +/** + * xilinx_vdma_start_transfer - Starts VDMA transfer + * @chan: Driver specific channel struct pointer + */ +static void xilinx_vdma_start_transfer(struct xilinx_vdma_chan *chan) +{ + struct xilinx_vdma_config *config = &chan->config; + struct xilinx_vdma_tx_descriptor *desc; + unsigned long flags; + u32 reg; + struct xilinx_vdma_tx_segment *head, *tail = NULL; + + if (chan->err) + return; + + spin_lock_irqsave(&chan->lock, flags); + + /* There's already an active descriptor, bail out. */ + if (chan->active_desc) + goto out_unlock; + + if (list_empty(&chan->pending_list)) + goto out_unlock; + + desc = list_first_entry(&chan->pending_list, + struct xilinx_vdma_tx_descriptor, node); + + /* If it is SG mode and hardware is busy, cannot submit */ + if (chan->has_sg && xilinx_vdma_is_running(chan) && + !xilinx_vdma_is_idle(chan)) { + dev_dbg(chan->dev, "DMA controller still busy\n"); + goto out_unlock; + } + + /* + * If hardware is idle, then all descriptors on the running lists are + * done, start new transfers + */ + if (chan->has_sg) { + head = list_first_entry(&desc->segments, + struct xilinx_vdma_tx_segment, node); + tail = list_entry(desc->segments.prev, + struct xilinx_vdma_tx_segment, node); + + vdma_ctrl_write(chan, XILINX_VDMA_REG_CURDESC, head->phys); + } + + /* Configure the hardware using info in the config structure */ + reg = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR); + + if (config->frm_cnt_en) + reg |= XILINX_VDMA_DMACR_FRAMECNT_EN; + else + reg &= ~XILINX_VDMA_DMACR_FRAMECNT_EN; + + /* + * With SG, start with circular mode, so that BDs can be fetched. + * In direct register mode, if not parking, enable circular mode + */ + if (chan->has_sg || !config->park) + reg |= XILINX_VDMA_DMACR_CIRC_EN; + + if (config->park) + reg &= ~XILINX_VDMA_DMACR_CIRC_EN; + + vdma_ctrl_write(chan, XILINX_VDMA_REG_DMACR, reg); + + if (config->park && (config->park_frm >= 0) && + (config->park_frm < chan->num_frms)) { + if (chan->direction == DMA_MEM_TO_DEV) + vdma_write(chan, XILINX_VDMA_REG_PARK_PTR, + config->park_frm << + XILINX_VDMA_PARK_PTR_RD_REF_SHIFT); + else + vdma_write(chan, XILINX_VDMA_REG_PARK_PTR, + config->park_frm << + XILINX_VDMA_PARK_PTR_WR_REF_SHIFT); + } + + /* Start the hardware */ + xilinx_vdma_start(chan); + + if (chan->err) + goto out_unlock; + + /* Start the transfer */ + if (chan->has_sg) { + vdma_ctrl_write(chan, XILINX_VDMA_REG_TAILDESC, tail->phys); + } else { + struct xilinx_vdma_tx_segment *segment, *last = NULL; + int i = 0; + + list_for_each_entry(segment, &desc->segments, node) { + vdma_desc_write(chan, + XILINX_VDMA_REG_START_ADDRESS(i++), + segment->hw.buf_addr); + last = segment; + } + + if (!last) + goto out_unlock; + + /* HW expects these parameters to be same for one transaction */ + vdma_desc_write(chan, XILINX_VDMA_REG_HSIZE, last->hw.hsize); + vdma_desc_write(chan, XILINX_VDMA_REG_FRMDLY_STRIDE, + last->hw.stride); + vdma_desc_write(chan, XILINX_VDMA_REG_VSIZE, last->hw.vsize); + } + + list_del(&desc->node); + chan->active_desc = desc; + +out_unlock: + spin_unlock_irqrestore(&chan->lock, flags); +} + +/** + * xilinx_vdma_issue_pending - Issue pending transactions + * @dchan: DMA channel + */ +static void xilinx_vdma_issue_pending(struct dma_chan *dchan) +{ + struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan); + + xilinx_vdma_start_transfer(chan); +} + +/** + * xilinx_vdma_complete_descriptor - Mark the active descriptor as complete + * @chan : xilinx DMA channel + * + * CONTEXT: hardirq + */ +static void xilinx_vdma_complete_descriptor(struct xilinx_vdma_chan *chan) +{ + struct xilinx_vdma_tx_descriptor *desc; + unsigned long flags; + + spin_lock_irqsave(&chan->lock, flags); + + desc = chan->active_desc; + if (!desc) { + dev_dbg(chan->dev, "no running descriptors\n"); + goto out_unlock; + } + + dma_cookie_complete(&desc->async_tx); + list_add_tail(&desc->node, &chan->done_list); + + chan->active_desc = NULL; + +out_unlock: + spin_unlock_irqrestore(&chan->lock, flags); +} + +/** + * xilinx_vdma_reset - Reset VDMA channel + * @chan: Driver specific VDMA channel + * + * Return: '0' on success and failure value on error + */ +static int xilinx_vdma_reset(struct xilinx_vdma_chan *chan) +{ + int loop = XILINX_VDMA_LOOP_COUNT; + u32 tmp; + + vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RESET); + + tmp = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) & + XILINX_VDMA_DMACR_RESET; + + /* Wait for the hardware to finish reset */ + do { + tmp = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) & + XILINX_VDMA_DMACR_RESET; + } while (loop-- && tmp); + + if (!loop) { + dev_err(chan->dev, "reset timeout, cr %x, sr %x\n", + vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR), + vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR)); + return -ETIMEDOUT; + } + + chan->err = false; + + return 0; +} + +/** + * xilinx_vdma_chan_reset - Reset VDMA channel and enable interrupts + * @chan: Driver specific VDMA channel + * + * Return: '0' on success and failure value on error + */ +static int xilinx_vdma_chan_reset(struct xilinx_vdma_chan *chan) +{ + int err; + + /* Reset VDMA */ + err = xilinx_vdma_reset(chan); + if (err) + return err; + + /* Enable interrupts */ + vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR, + XILINX_VDMA_DMAXR_ALL_IRQ_MASK); + + return 0; +} + +/** + * xilinx_vdma_irq_handler - VDMA Interrupt handler + * @irq: IRQ number + * @data: Pointer to the Xilinx VDMA channel structure + * + * Return: IRQ_HANDLED/IRQ_NONE + */ +static irqreturn_t xilinx_vdma_irq_handler(int irq, void *data) +{ + struct xilinx_vdma_chan *chan = data; + u32 status; + + /* Read the status and ack the interrupts. */ + status = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR); + if (!(status & XILINX_VDMA_DMAXR_ALL_IRQ_MASK)) + return IRQ_NONE; + + vdma_ctrl_write(chan, XILINX_VDMA_REG_DMASR, + status & XILINX_VDMA_DMAXR_ALL_IRQ_MASK); + + if (status & XILINX_VDMA_DMASR_ERR_IRQ) { + /* + * An error occurred. If C_FLUSH_ON_FSYNC is enabled and the + * error is recoverable, ignore it. Otherwise flag the error. + * + * Only recoverable errors can be cleared in the DMASR register, + * make sure not to write to other error bits to 1. + */ + u32 errors = status & XILINX_VDMA_DMASR_ALL_ERR_MASK; + vdma_ctrl_write(chan, XILINX_VDMA_REG_DMASR, + errors & XILINX_VDMA_DMASR_ERR_RECOVER_MASK); + + if (!chan->flush_on_fsync || + (errors & ~XILINX_VDMA_DMASR_ERR_RECOVER_MASK)) { + dev_err(chan->dev, + "Channel %p has errors %x, cdr %x tdr %x\n", + chan, errors, + vdma_ctrl_read(chan, XILINX_VDMA_REG_CURDESC), + vdma_ctrl_read(chan, XILINX_VDMA_REG_TAILDESC)); + chan->err = true; + } + } + + if (status & XILINX_VDMA_DMASR_DLY_CNT_IRQ) { + /* + * Device takes too long to do the transfer when user requires + * responsiveness. + */ + dev_dbg(chan->dev, "Inter-packet latency too long\n"); + } + + if (status & XILINX_VDMA_DMASR_FRM_CNT_IRQ) { + xilinx_vdma_complete_descriptor(chan); + xilinx_vdma_start_transfer(chan); + } + + tasklet_schedule(&chan->tasklet); + return IRQ_HANDLED; +} + +/** + * xilinx_vdma_tx_submit - Submit DMA transaction + * @tx: Async transaction descriptor + * + * Return: cookie value on success and failure value on error + */ +static dma_cookie_t xilinx_vdma_tx_submit(struct dma_async_tx_descriptor *tx) +{ + struct xilinx_vdma_tx_descriptor *desc = to_vdma_tx_descriptor(tx); + struct xilinx_vdma_chan *chan = to_xilinx_chan(tx->chan); + dma_cookie_t cookie; + unsigned long flags; + int err; + + if (chan->err) { + /* + * If reset fails, need to hard reset the system. + * Channel is no longer functional + */ + err = xilinx_vdma_chan_reset(chan); + if (err < 0) + return err; + } + + spin_lock_irqsave(&chan->lock, flags); + + cookie = dma_cookie_assign(tx); + + /* Append the transaction to the pending transactions queue. */ + list_add_tail(&desc->node, &chan->pending_list); + + /* Free the allocated desc */ + chan->allocated_desc = NULL; + + spin_unlock_irqrestore(&chan->lock, flags); + + return cookie; +} + +/** + * xilinx_vdma_dma_prep_interleaved - prepare a descriptor for a + * DMA_SLAVE transaction + * @dchan: DMA channel + * @xt: Interleaved template pointer + * @flags: transfer ack flags + * + * Return: Async transaction descriptor on success and NULL on failure + */ +static struct dma_async_tx_descriptor * +xilinx_vdma_dma_prep_interleaved(struct dma_chan *dchan, + struct dma_interleaved_template *xt, + unsigned long flags) +{ + struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan); + struct xilinx_vdma_tx_descriptor *desc; + struct xilinx_vdma_tx_segment *segment, *prev = NULL; + struct xilinx_vdma_desc_hw *hw; + + if (!is_slave_direction(xt->dir)) + return NULL; + + if (!xt->numf || !xt->sgl[0].size) + return NULL; + + if (xt->frame_size != 1) + return NULL; + + /* Allocate a transaction descriptor. */ + desc = xilinx_vdma_alloc_tx_descriptor(chan); + if (!desc) + return NULL; + + dma_async_tx_descriptor_init(&desc->async_tx, &chan->common); + desc->async_tx.tx_submit = xilinx_vdma_tx_submit; + async_tx_ack(&desc->async_tx); + + /* Allocate the link descriptor from DMA pool */ + segment = xilinx_vdma_alloc_tx_segment(chan); + if (!segment) + goto error; + + /* Fill in the hardware descriptor */ + hw = &segment->hw; + hw->vsize = xt->numf; + hw->hsize = xt->sgl[0].size; + hw->stride = (xt->sgl[0].icg + xt->sgl[0].size) << + XILINX_VDMA_FRMDLY_STRIDE_STRIDE_SHIFT; + hw->stride |= chan->config.frm_dly << + XILINX_VDMA_FRMDLY_STRIDE_FRMDLY_SHIFT; + + if (xt->dir != DMA_MEM_TO_DEV) + hw->buf_addr = xt->dst_start; + else + hw->buf_addr = xt->src_start; + + /* Link the previous next descriptor to current */ + if (!list_empty(&desc->segments)) { + prev = list_last_entry(&desc->segments, + struct xilinx_vdma_tx_segment, node); + prev->hw.next_desc = segment->phys; + } + + /* Insert the segment into the descriptor segments list. */ + list_add_tail(&segment->node, &desc->segments); + + prev = segment; + + /* Link the last hardware descriptor with the first. */ + segment = list_first_entry(&desc->segments, + struct xilinx_vdma_tx_segment, node); + prev->hw.next_desc = segment->phys; + + return &desc->async_tx; + +error: + xilinx_vdma_free_tx_descriptor(chan, desc); + return NULL; +} + +/** + * xilinx_vdma_terminate_all - Halt the channel and free descriptors + * @chan: Driver specific VDMA Channel pointer + */ +static int xilinx_vdma_terminate_all(struct dma_chan *dchan) +{ + struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan); + + /* Halt the DMA engine */ + xilinx_vdma_halt(chan); + + /* Remove and free all of the descriptors in the lists */ + xilinx_vdma_free_descriptors(chan); + + return 0; +} + +/** + * xilinx_vdma_channel_set_config - Configure VDMA channel + * Run-time configuration for Axi VDMA, supports: + * . halt the channel + * . configure interrupt coalescing and inter-packet delay threshold + * . start/stop parking + * . enable genlock + * + * @dchan: DMA channel + * @cfg: VDMA device configuration pointer + * + * Return: '0' on success and failure value on error + */ +int xilinx_vdma_channel_set_config(struct dma_chan *dchan, + struct xilinx_vdma_config *cfg) +{ + struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan); + u32 dmacr; + + if (cfg->reset) + return xilinx_vdma_chan_reset(chan); + + dmacr = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR); + + chan->config.frm_dly = cfg->frm_dly; + chan->config.park = cfg->park; + + /* genlock settings */ + chan->config.gen_lock = cfg->gen_lock; + chan->config.master = cfg->master; + + if (cfg->gen_lock && chan->genlock) { + dmacr |= XILINX_VDMA_DMACR_GENLOCK_EN; + dmacr |= cfg->master << XILINX_VDMA_DMACR_MASTER_SHIFT; + } + + chan->config.frm_cnt_en = cfg->frm_cnt_en; + if (cfg->park) + chan->config.park_frm = cfg->park_frm; + else + chan->config.park_frm = -1; + + chan->config.coalesc = cfg->coalesc; + chan->config.delay = cfg->delay; + + if (cfg->coalesc <= XILINX_VDMA_DMACR_FRAME_COUNT_MAX) { + dmacr |= cfg->coalesc << XILINX_VDMA_DMACR_FRAME_COUNT_SHIFT; + chan->config.coalesc = cfg->coalesc; + } + + if (cfg->delay <= XILINX_VDMA_DMACR_DELAY_MAX) { + dmacr |= cfg->delay << XILINX_VDMA_DMACR_DELAY_SHIFT; + chan->config.delay = cfg->delay; + } + + /* FSync Source selection */ + dmacr &= ~XILINX_VDMA_DMACR_FSYNCSRC_MASK; + dmacr |= cfg->ext_fsync << XILINX_VDMA_DMACR_FSYNCSRC_SHIFT; + + vdma_ctrl_write(chan, XILINX_VDMA_REG_DMACR, dmacr); + + return 0; +} +EXPORT_SYMBOL(xilinx_vdma_channel_set_config); + +/* ----------------------------------------------------------------------------- + * Probe and remove + */ + +/** + * xilinx_vdma_chan_remove - Per Channel remove function + * @chan: Driver specific VDMA channel + */ +static void xilinx_vdma_chan_remove(struct xilinx_vdma_chan *chan) +{ + /* Disable all interrupts */ + vdma_ctrl_clr(chan, XILINX_VDMA_REG_DMACR, + XILINX_VDMA_DMAXR_ALL_IRQ_MASK); + + if (chan->irq > 0) + free_irq(chan->irq, chan); + + tasklet_kill(&chan->tasklet); + + list_del(&chan->common.device_node); +} + +/** + * xilinx_vdma_chan_probe - Per Channel Probing + * It get channel features from the device tree entry and + * initialize special channel handling routines + * + * @xdev: Driver specific device structure + * @node: Device node + * + * Return: '0' on success and failure value on error + */ +static int xilinx_vdma_chan_probe(struct xilinx_vdma_device *xdev, + struct device_node *node) +{ + struct xilinx_vdma_chan *chan; + bool has_dre = false; + u32 value, width; + int err; + + /* Allocate and initialize the channel structure */ + chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL); + if (!chan) + return -ENOMEM; + + chan->dev = xdev->dev; + chan->xdev = xdev; + chan->has_sg = xdev->has_sg; + + spin_lock_init(&chan->lock); + INIT_LIST_HEAD(&chan->pending_list); + INIT_LIST_HEAD(&chan->done_list); + + /* Retrieve the channel properties from the device tree */ + has_dre = of_property_read_bool(node, "xlnx,include-dre"); + + chan->genlock = of_property_read_bool(node, "xlnx,genlock-mode"); + + err = of_property_read_u32(node, "xlnx,datawidth", &value); + if (err) { + dev_err(xdev->dev, "missing xlnx,datawidth property\n"); + return err; + } + width = value >> 3; /* Convert bits to bytes */ + + /* If data width is greater than 8 bytes, DRE is not in hw */ + if (width > 8) + has_dre = false; + + if (!has_dre) + xdev->common.copy_align = fls(width - 1); + + if (of_device_is_compatible(node, "xlnx,axi-vdma-mm2s-channel")) { + chan->direction = DMA_MEM_TO_DEV; + chan->id = 0; + + chan->ctrl_offset = XILINX_VDMA_MM2S_CTRL_OFFSET; + chan->desc_offset = XILINX_VDMA_MM2S_DESC_OFFSET; + + if (xdev->flush_on_fsync == XILINX_VDMA_FLUSH_BOTH || + xdev->flush_on_fsync == XILINX_VDMA_FLUSH_MM2S) + chan->flush_on_fsync = true; + } else if (of_device_is_compatible(node, + "xlnx,axi-vdma-s2mm-channel")) { + chan->direction = DMA_DEV_TO_MEM; + chan->id = 1; + + chan->ctrl_offset = XILINX_VDMA_S2MM_CTRL_OFFSET; + chan->desc_offset = XILINX_VDMA_S2MM_DESC_OFFSET; + + if (xdev->flush_on_fsync == XILINX_VDMA_FLUSH_BOTH || + xdev->flush_on_fsync == XILINX_VDMA_FLUSH_S2MM) + chan->flush_on_fsync = true; + } else { + dev_err(xdev->dev, "Invalid channel compatible node\n"); + return -EINVAL; + } + + /* Request the interrupt */ + chan->irq = irq_of_parse_and_map(node, 0); + err = request_irq(chan->irq, xilinx_vdma_irq_handler, IRQF_SHARED, + "xilinx-vdma-controller", chan); + if (err) { + dev_err(xdev->dev, "unable to request IRQ %d\n", chan->irq); + return err; + } + + /* Initialize the tasklet */ + tasklet_init(&chan->tasklet, xilinx_vdma_do_tasklet, + (unsigned long)chan); + + /* + * Initialize the DMA channel and add it to the DMA engine channels + * list. + */ + chan->common.device = &xdev->common; + + list_add_tail(&chan->common.device_node, &xdev->common.channels); + xdev->chan[chan->id] = chan; + + /* Reset the channel */ + err = xilinx_vdma_chan_reset(chan); + if (err < 0) { + dev_err(xdev->dev, "Reset channel failed\n"); + return err; + } + + return 0; +} + +/** + * of_dma_xilinx_xlate - Translation function + * @dma_spec: Pointer to DMA specifier as found in the device tree + * @ofdma: Pointer to DMA controller data + * + * Return: DMA channel pointer on success and NULL on error + */ +static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct xilinx_vdma_device *xdev = ofdma->of_dma_data; + int chan_id = dma_spec->args[0]; + + if (chan_id >= XILINX_VDMA_MAX_CHANS_PER_DEVICE) + return NULL; + + return dma_get_slave_channel(&xdev->chan[chan_id]->common); +} + +/** + * xilinx_vdma_probe - Driver probe function + * @pdev: Pointer to the platform_device structure + * + * Return: '0' on success and failure value on error + */ +static int xilinx_vdma_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct xilinx_vdma_device *xdev; + struct device_node *child; + struct resource *io; + u32 num_frames; + int i, err; + + /* Allocate and initialize the DMA engine structure */ + xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL); + if (!xdev) + return -ENOMEM; + + xdev->dev = &pdev->dev; + + /* Request and map I/O memory */ + io = platform_get_resource(pdev, IORESOURCE_MEM, 0); + xdev->regs = devm_ioremap_resource(&pdev->dev, io); + if (IS_ERR(xdev->regs)) + return PTR_ERR(xdev->regs); + + /* Retrieve the DMA engine properties from the device tree */ + xdev->has_sg = of_property_read_bool(node, "xlnx,include-sg"); + + err = of_property_read_u32(node, "xlnx,num-fstores", &num_frames); + if (err < 0) { + dev_err(xdev->dev, "missing xlnx,num-fstores property\n"); + return err; + } + + err = of_property_read_u32(node, "xlnx,flush-fsync", + &xdev->flush_on_fsync); + if (err < 0) + dev_warn(xdev->dev, "missing xlnx,flush-fsync property\n"); + + /* Initialize the DMA engine */ + xdev->common.dev = &pdev->dev; + + INIT_LIST_HEAD(&xdev->common.channels); + dma_cap_set(DMA_SLAVE, xdev->common.cap_mask); + dma_cap_set(DMA_PRIVATE, xdev->common.cap_mask); + + xdev->common.device_alloc_chan_resources = + xilinx_vdma_alloc_chan_resources; + xdev->common.device_free_chan_resources = + xilinx_vdma_free_chan_resources; + xdev->common.device_prep_interleaved_dma = + xilinx_vdma_dma_prep_interleaved; + xdev->common.device_terminate_all = xilinx_vdma_terminate_all; + xdev->common.device_tx_status = xilinx_vdma_tx_status; + xdev->common.device_issue_pending = xilinx_vdma_issue_pending; + + platform_set_drvdata(pdev, xdev); + + /* Initialize the channels */ + for_each_child_of_node(node, child) { + err = xilinx_vdma_chan_probe(xdev, child); + if (err < 0) + goto error; + } + + for (i = 0; i < XILINX_VDMA_MAX_CHANS_PER_DEVICE; i++) + if (xdev->chan[i]) + xdev->chan[i]->num_frms = num_frames; + + /* Register the DMA engine with the core */ + dma_async_device_register(&xdev->common); + + err = of_dma_controller_register(node, of_dma_xilinx_xlate, + xdev); + if (err < 0) { + dev_err(&pdev->dev, "Unable to register DMA to DT\n"); + dma_async_device_unregister(&xdev->common); + goto error; + } + + dev_info(&pdev->dev, "Xilinx AXI VDMA Engine Driver Probed!!\n"); + + return 0; + +error: + for (i = 0; i < XILINX_VDMA_MAX_CHANS_PER_DEVICE; i++) + if (xdev->chan[i]) + xilinx_vdma_chan_remove(xdev->chan[i]); + + return err; +} + +/** + * xilinx_vdma_remove - Driver remove function + * @pdev: Pointer to the platform_device structure + * + * Return: Always '0' + */ +static int xilinx_vdma_remove(struct platform_device *pdev) +{ + struct xilinx_vdma_device *xdev = platform_get_drvdata(pdev); + int i; + + of_dma_controller_free(pdev->dev.of_node); + + dma_async_device_unregister(&xdev->common); + + for (i = 0; i < XILINX_VDMA_MAX_CHANS_PER_DEVICE; i++) + if (xdev->chan[i]) + xilinx_vdma_chan_remove(xdev->chan[i]); + + return 0; +} + +static const struct of_device_id xilinx_vdma_of_ids[] = { + { .compatible = "xlnx,axi-vdma-1.00.a",}, + {} +}; + +static struct platform_driver xilinx_vdma_driver = { + .driver = { + .name = "xilinx-vdma", + .of_match_table = xilinx_vdma_of_ids, + }, + .probe = xilinx_vdma_probe, + .remove = xilinx_vdma_remove, +}; + +module_platform_driver(xilinx_vdma_driver); + +MODULE_AUTHOR("Xilinx, Inc."); +MODULE_DESCRIPTION("Xilinx VDMA driver"); +MODULE_LICENSE("GPL v2"); |