diff options
Diffstat (limited to 'drivers/dma/tegra20-apb-dma.c')
| -rw-r--r-- | drivers/dma/tegra20-apb-dma.c | 1687 |
1 files changed, 1687 insertions, 0 deletions
diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c new file mode 100644 index 0000000000..063022f9df --- /dev/null +++ b/drivers/dma/tegra20-apb-dma.c @@ -0,0 +1,1687 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * DMA driver for Nvidia's Tegra20 APB DMA controller. + * + * Copyright (c) 2012-2013, NVIDIA CORPORATION. All rights reserved. + */ + +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_dma.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/pm_runtime.h> +#include <linux/reset.h> +#include <linux/slab.h> +#include <linux/wait.h> + +#include "dmaengine.h" + +#define CREATE_TRACE_POINTS +#include <trace/events/tegra_apb_dma.h> + +#define TEGRA_APBDMA_GENERAL 0x0 +#define TEGRA_APBDMA_GENERAL_ENABLE BIT(31) + +#define TEGRA_APBDMA_CONTROL 0x010 +#define TEGRA_APBDMA_IRQ_MASK 0x01c +#define TEGRA_APBDMA_IRQ_MASK_SET 0x020 + +/* CSR register */ +#define TEGRA_APBDMA_CHAN_CSR 0x00 +#define TEGRA_APBDMA_CSR_ENB BIT(31) +#define TEGRA_APBDMA_CSR_IE_EOC BIT(30) +#define TEGRA_APBDMA_CSR_HOLD BIT(29) +#define TEGRA_APBDMA_CSR_DIR BIT(28) +#define TEGRA_APBDMA_CSR_ONCE BIT(27) +#define TEGRA_APBDMA_CSR_FLOW BIT(21) +#define TEGRA_APBDMA_CSR_REQ_SEL_SHIFT 16 +#define TEGRA_APBDMA_CSR_REQ_SEL_MASK 0x1F +#define TEGRA_APBDMA_CSR_WCOUNT_MASK 0xFFFC + +/* STATUS register */ +#define TEGRA_APBDMA_CHAN_STATUS 0x004 +#define TEGRA_APBDMA_STATUS_BUSY BIT(31) +#define TEGRA_APBDMA_STATUS_ISE_EOC BIT(30) +#define TEGRA_APBDMA_STATUS_HALT BIT(29) +#define TEGRA_APBDMA_STATUS_PING_PONG BIT(28) +#define TEGRA_APBDMA_STATUS_COUNT_SHIFT 2 +#define TEGRA_APBDMA_STATUS_COUNT_MASK 0xFFFC + +#define TEGRA_APBDMA_CHAN_CSRE 0x00C +#define TEGRA_APBDMA_CHAN_CSRE_PAUSE BIT(31) + +/* AHB memory address */ +#define TEGRA_APBDMA_CHAN_AHBPTR 0x010 + +/* AHB sequence register */ +#define TEGRA_APBDMA_CHAN_AHBSEQ 0x14 +#define TEGRA_APBDMA_AHBSEQ_INTR_ENB BIT(31) +#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_8 (0 << 28) +#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_16 (1 << 28) +#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32 (2 << 28) +#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_64 (3 << 28) +#define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_128 (4 << 28) +#define TEGRA_APBDMA_AHBSEQ_DATA_SWAP BIT(27) +#define TEGRA_APBDMA_AHBSEQ_BURST_1 (4 << 24) +#define TEGRA_APBDMA_AHBSEQ_BURST_4 (5 << 24) +#define TEGRA_APBDMA_AHBSEQ_BURST_8 (6 << 24) +#define TEGRA_APBDMA_AHBSEQ_DBL_BUF BIT(19) +#define TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT 16 +#define TEGRA_APBDMA_AHBSEQ_WRAP_NONE 0 + +/* APB address */ +#define TEGRA_APBDMA_CHAN_APBPTR 0x018 + +/* APB sequence register */ +#define TEGRA_APBDMA_CHAN_APBSEQ 0x01c +#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8 (0 << 28) +#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16 (1 << 28) +#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32 (2 << 28) +#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64 (3 << 28) +#define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_128 (4 << 28) +#define TEGRA_APBDMA_APBSEQ_DATA_SWAP BIT(27) +#define TEGRA_APBDMA_APBSEQ_WRAP_WORD_1 (1 << 16) + +/* Tegra148 specific registers */ +#define TEGRA_APBDMA_CHAN_WCOUNT 0x20 + +#define TEGRA_APBDMA_CHAN_WORD_TRANSFER 0x24 + +/* + * If any burst is in flight and DMA paused then this is the time to complete + * on-flight burst and update DMA status register. + */ +#define TEGRA_APBDMA_BURST_COMPLETE_TIME 20 + +/* Channel base address offset from APBDMA base address */ +#define TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET 0x1000 + +#define TEGRA_APBDMA_SLAVE_ID_INVALID (TEGRA_APBDMA_CSR_REQ_SEL_MASK + 1) + +struct tegra_dma; + +/* + * tegra_dma_chip_data Tegra chip specific DMA data + * @nr_channels: Number of channels available in the controller. + * @channel_reg_size: Channel register size/stride. + * @max_dma_count: Maximum DMA transfer count supported by DMA controller. + * @support_channel_pause: Support channel wise pause of dma. + * @support_separate_wcount_reg: Support separate word count register. + */ +struct tegra_dma_chip_data { + unsigned int nr_channels; + unsigned int channel_reg_size; + unsigned int max_dma_count; + bool support_channel_pause; + bool support_separate_wcount_reg; +}; + +/* DMA channel registers */ +struct tegra_dma_channel_regs { + u32 csr; + u32 ahb_ptr; + u32 apb_ptr; + u32 ahb_seq; + u32 apb_seq; + u32 wcount; +}; + +/* + * tegra_dma_sg_req: DMA request details to configure hardware. This + * contains the details for one transfer to configure DMA hw. + * The client's request for data transfer can be broken into multiple + * sub-transfer as per requester details and hw support. + * This sub transfer get added in the list of transfer and point to Tegra + * DMA descriptor which manages the transfer details. + */ +struct tegra_dma_sg_req { + struct tegra_dma_channel_regs ch_regs; + unsigned int req_len; + bool configured; + bool last_sg; + struct list_head node; + struct tegra_dma_desc *dma_desc; + unsigned int words_xferred; +}; + +/* + * tegra_dma_desc: Tegra DMA descriptors which manages the client requests. + * This descriptor keep track of transfer status, callbacks and request + * counts etc. + */ +struct tegra_dma_desc { + struct dma_async_tx_descriptor txd; + unsigned int bytes_requested; + unsigned int bytes_transferred; + enum dma_status dma_status; + struct list_head node; + struct list_head tx_list; + struct list_head cb_node; + unsigned int cb_count; +}; + +struct tegra_dma_channel; + +typedef void (*dma_isr_handler)(struct tegra_dma_channel *tdc, + bool to_terminate); + +/* tegra_dma_channel: Channel specific information */ +struct tegra_dma_channel { + struct dma_chan dma_chan; + char name[12]; + bool config_init; + unsigned int id; + void __iomem *chan_addr; + spinlock_t lock; + bool busy; + struct tegra_dma *tdma; + bool cyclic; + + /* Different lists for managing the requests */ + struct list_head free_sg_req; + struct list_head pending_sg_req; + struct list_head free_dma_desc; + struct list_head cb_desc; + + /* ISR handler and tasklet for bottom half of isr handling */ + dma_isr_handler isr_handler; + struct tasklet_struct tasklet; + + /* Channel-slave specific configuration */ + unsigned int slave_id; + struct dma_slave_config dma_sconfig; + struct tegra_dma_channel_regs channel_reg; + + struct wait_queue_head wq; +}; + +/* tegra_dma: Tegra DMA specific information */ +struct tegra_dma { + struct dma_device dma_dev; + struct device *dev; + struct clk *dma_clk; + struct reset_control *rst; + spinlock_t global_lock; + void __iomem *base_addr; + const struct tegra_dma_chip_data *chip_data; + + /* + * Counter for managing global pausing of the DMA controller. + * Only applicable for devices that don't support individual + * channel pausing. + */ + u32 global_pause_count; + + /* Last member of the structure */ + struct tegra_dma_channel channels[]; +}; + +static inline void tdma_write(struct tegra_dma *tdma, u32 reg, u32 val) +{ + writel(val, tdma->base_addr + reg); +} + +static inline void tdc_write(struct tegra_dma_channel *tdc, + u32 reg, u32 val) +{ + writel(val, tdc->chan_addr + reg); +} + +static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg) +{ + return readl(tdc->chan_addr + reg); +} + +static inline struct tegra_dma_channel *to_tegra_dma_chan(struct dma_chan *dc) +{ + return container_of(dc, struct tegra_dma_channel, dma_chan); +} + +static inline struct tegra_dma_desc * +txd_to_tegra_dma_desc(struct dma_async_tx_descriptor *td) +{ + return container_of(td, struct tegra_dma_desc, txd); +} + +static inline struct device *tdc2dev(struct tegra_dma_channel *tdc) +{ + return &tdc->dma_chan.dev->device; +} + +static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *tx); + +/* Get DMA desc from free list, if not there then allocate it. */ +static struct tegra_dma_desc *tegra_dma_desc_get(struct tegra_dma_channel *tdc) +{ + struct tegra_dma_desc *dma_desc; + unsigned long flags; + + spin_lock_irqsave(&tdc->lock, flags); + + /* Do not allocate if desc are waiting for ack */ + list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) { + if (async_tx_test_ack(&dma_desc->txd) && !dma_desc->cb_count) { + list_del(&dma_desc->node); + spin_unlock_irqrestore(&tdc->lock, flags); + dma_desc->txd.flags = 0; + return dma_desc; + } + } + + spin_unlock_irqrestore(&tdc->lock, flags); + + /* Allocate DMA desc */ + dma_desc = kzalloc(sizeof(*dma_desc), GFP_NOWAIT); + if (!dma_desc) + return NULL; + + dma_async_tx_descriptor_init(&dma_desc->txd, &tdc->dma_chan); + dma_desc->txd.tx_submit = tegra_dma_tx_submit; + dma_desc->txd.flags = 0; + + return dma_desc; +} + +static void tegra_dma_desc_put(struct tegra_dma_channel *tdc, + struct tegra_dma_desc *dma_desc) +{ + unsigned long flags; + + spin_lock_irqsave(&tdc->lock, flags); + if (!list_empty(&dma_desc->tx_list)) + list_splice_init(&dma_desc->tx_list, &tdc->free_sg_req); + list_add_tail(&dma_desc->node, &tdc->free_dma_desc); + spin_unlock_irqrestore(&tdc->lock, flags); +} + +static struct tegra_dma_sg_req * +tegra_dma_sg_req_get(struct tegra_dma_channel *tdc) +{ + struct tegra_dma_sg_req *sg_req; + unsigned long flags; + + spin_lock_irqsave(&tdc->lock, flags); + if (!list_empty(&tdc->free_sg_req)) { + sg_req = list_first_entry(&tdc->free_sg_req, typeof(*sg_req), + node); + list_del(&sg_req->node); + spin_unlock_irqrestore(&tdc->lock, flags); + return sg_req; + } + spin_unlock_irqrestore(&tdc->lock, flags); + + sg_req = kzalloc(sizeof(*sg_req), GFP_NOWAIT); + + return sg_req; +} + +static int tegra_dma_slave_config(struct dma_chan *dc, + struct dma_slave_config *sconfig) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + + if (!list_empty(&tdc->pending_sg_req)) { + dev_err(tdc2dev(tdc), "Configuration not allowed\n"); + return -EBUSY; + } + + memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig)); + tdc->config_init = true; + + return 0; +} + +static void tegra_dma_global_pause(struct tegra_dma_channel *tdc, + bool wait_for_burst_complete) +{ + struct tegra_dma *tdma = tdc->tdma; + + spin_lock(&tdma->global_lock); + + if (tdc->tdma->global_pause_count == 0) { + tdma_write(tdma, TEGRA_APBDMA_GENERAL, 0); + if (wait_for_burst_complete) + udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME); + } + + tdc->tdma->global_pause_count++; + + spin_unlock(&tdma->global_lock); +} + +static void tegra_dma_global_resume(struct tegra_dma_channel *tdc) +{ + struct tegra_dma *tdma = tdc->tdma; + + spin_lock(&tdma->global_lock); + + if (WARN_ON(tdc->tdma->global_pause_count == 0)) + goto out; + + if (--tdc->tdma->global_pause_count == 0) + tdma_write(tdma, TEGRA_APBDMA_GENERAL, + TEGRA_APBDMA_GENERAL_ENABLE); + +out: + spin_unlock(&tdma->global_lock); +} + +static void tegra_dma_pause(struct tegra_dma_channel *tdc, + bool wait_for_burst_complete) +{ + struct tegra_dma *tdma = tdc->tdma; + + if (tdma->chip_data->support_channel_pause) { + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE, + TEGRA_APBDMA_CHAN_CSRE_PAUSE); + if (wait_for_burst_complete) + udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME); + } else { + tegra_dma_global_pause(tdc, wait_for_burst_complete); + } +} + +static void tegra_dma_resume(struct tegra_dma_channel *tdc) +{ + struct tegra_dma *tdma = tdc->tdma; + + if (tdma->chip_data->support_channel_pause) + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE, 0); + else + tegra_dma_global_resume(tdc); +} + +static void tegra_dma_stop(struct tegra_dma_channel *tdc) +{ + u32 csr, status; + + /* Disable interrupts */ + csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR); + csr &= ~TEGRA_APBDMA_CSR_IE_EOC; + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr); + + /* Disable DMA */ + csr &= ~TEGRA_APBDMA_CSR_ENB; + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr); + + /* Clear interrupt status if it is there */ + status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); + if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { + dev_dbg(tdc2dev(tdc), "%s():clearing interrupt\n", __func__); + tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status); + } + tdc->busy = false; +} + +static void tegra_dma_start(struct tegra_dma_channel *tdc, + struct tegra_dma_sg_req *sg_req) +{ + struct tegra_dma_channel_regs *ch_regs = &sg_req->ch_regs; + + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, ch_regs->csr); + tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_regs->apb_seq); + tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_regs->apb_ptr); + tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_regs->ahb_seq); + tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_regs->ahb_ptr); + if (tdc->tdma->chip_data->support_separate_wcount_reg) + tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT, ch_regs->wcount); + + /* Start DMA */ + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, + ch_regs->csr | TEGRA_APBDMA_CSR_ENB); +} + +static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc, + struct tegra_dma_sg_req *nsg_req) +{ + unsigned long status; + + /* + * The DMA controller reloads the new configuration for next transfer + * after last burst of current transfer completes. + * If there is no IEC status then this makes sure that last burst + * has not be completed. There may be case that last burst is on + * flight and so it can complete but because DMA is paused, it + * will not generates interrupt as well as not reload the new + * configuration. + * If there is already IEC status then interrupt handler need to + * load new configuration. + */ + tegra_dma_pause(tdc, false); + status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); + + /* + * If interrupt is pending then do nothing as the ISR will handle + * the programing for new request. + */ + if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { + dev_err(tdc2dev(tdc), + "Skipping new configuration as interrupt is pending\n"); + tegra_dma_resume(tdc); + return; + } + + /* Safe to program new configuration */ + tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, nsg_req->ch_regs.apb_ptr); + tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, nsg_req->ch_regs.ahb_ptr); + if (tdc->tdma->chip_data->support_separate_wcount_reg) + tdc_write(tdc, TEGRA_APBDMA_CHAN_WCOUNT, + nsg_req->ch_regs.wcount); + tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, + nsg_req->ch_regs.csr | TEGRA_APBDMA_CSR_ENB); + nsg_req->configured = true; + nsg_req->words_xferred = 0; + + tegra_dma_resume(tdc); +} + +static void tdc_start_head_req(struct tegra_dma_channel *tdc) +{ + struct tegra_dma_sg_req *sg_req; + + sg_req = list_first_entry(&tdc->pending_sg_req, typeof(*sg_req), node); + tegra_dma_start(tdc, sg_req); + sg_req->configured = true; + sg_req->words_xferred = 0; + tdc->busy = true; +} + +static void tdc_configure_next_head_desc(struct tegra_dma_channel *tdc) +{ + struct tegra_dma_sg_req *hsgreq, *hnsgreq; + + hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node); + if (!list_is_last(&hsgreq->node, &tdc->pending_sg_req)) { + hnsgreq = list_first_entry(&hsgreq->node, typeof(*hnsgreq), + node); + tegra_dma_configure_for_next(tdc, hnsgreq); + } +} + +static inline unsigned int +get_current_xferred_count(struct tegra_dma_channel *tdc, + struct tegra_dma_sg_req *sg_req, + unsigned long status) +{ + return sg_req->req_len - (status & TEGRA_APBDMA_STATUS_COUNT_MASK) - 4; +} + +static void tegra_dma_abort_all(struct tegra_dma_channel *tdc) +{ + struct tegra_dma_desc *dma_desc; + struct tegra_dma_sg_req *sgreq; + + while (!list_empty(&tdc->pending_sg_req)) { + sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), + node); + list_move_tail(&sgreq->node, &tdc->free_sg_req); + if (sgreq->last_sg) { + dma_desc = sgreq->dma_desc; + dma_desc->dma_status = DMA_ERROR; + list_add_tail(&dma_desc->node, &tdc->free_dma_desc); + + /* Add in cb list if it is not there. */ + if (!dma_desc->cb_count) + list_add_tail(&dma_desc->cb_node, + &tdc->cb_desc); + dma_desc->cb_count++; + } + } + tdc->isr_handler = NULL; +} + +static bool handle_continuous_head_request(struct tegra_dma_channel *tdc, + bool to_terminate) +{ + struct tegra_dma_sg_req *hsgreq; + + /* + * Check that head req on list should be in flight. + * If it is not in flight then abort transfer as + * looping of transfer can not continue. + */ + hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node); + if (!hsgreq->configured) { + tegra_dma_stop(tdc); + pm_runtime_put(tdc->tdma->dev); + dev_err(tdc2dev(tdc), "DMA transfer underflow, aborting DMA\n"); + tegra_dma_abort_all(tdc); + return false; + } + + /* Configure next request */ + if (!to_terminate) + tdc_configure_next_head_desc(tdc); + + return true; +} + +static void handle_once_dma_done(struct tegra_dma_channel *tdc, + bool to_terminate) +{ + struct tegra_dma_desc *dma_desc; + struct tegra_dma_sg_req *sgreq; + + tdc->busy = false; + sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node); + dma_desc = sgreq->dma_desc; + dma_desc->bytes_transferred += sgreq->req_len; + + list_del(&sgreq->node); + if (sgreq->last_sg) { + dma_desc->dma_status = DMA_COMPLETE; + dma_cookie_complete(&dma_desc->txd); + if (!dma_desc->cb_count) + list_add_tail(&dma_desc->cb_node, &tdc->cb_desc); + dma_desc->cb_count++; + list_add_tail(&dma_desc->node, &tdc->free_dma_desc); + } + list_add_tail(&sgreq->node, &tdc->free_sg_req); + + /* Do not start DMA if it is going to be terminate */ + if (to_terminate) + return; + + if (list_empty(&tdc->pending_sg_req)) { + pm_runtime_put(tdc->tdma->dev); + return; + } + + tdc_start_head_req(tdc); +} + +static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc, + bool to_terminate) +{ + struct tegra_dma_desc *dma_desc; + struct tegra_dma_sg_req *sgreq; + bool st; + + sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node); + dma_desc = sgreq->dma_desc; + /* if we dma for long enough the transfer count will wrap */ + dma_desc->bytes_transferred = + (dma_desc->bytes_transferred + sgreq->req_len) % + dma_desc->bytes_requested; + + /* Callback need to be call */ + if (!dma_desc->cb_count) + list_add_tail(&dma_desc->cb_node, &tdc->cb_desc); + dma_desc->cb_count++; + + sgreq->words_xferred = 0; + + /* If not last req then put at end of pending list */ + if (!list_is_last(&sgreq->node, &tdc->pending_sg_req)) { + list_move_tail(&sgreq->node, &tdc->pending_sg_req); + sgreq->configured = false; + st = handle_continuous_head_request(tdc, to_terminate); + if (!st) + dma_desc->dma_status = DMA_ERROR; + } +} + +static void tegra_dma_tasklet(struct tasklet_struct *t) +{ + struct tegra_dma_channel *tdc = from_tasklet(tdc, t, tasklet); + struct dmaengine_desc_callback cb; + struct tegra_dma_desc *dma_desc; + unsigned int cb_count; + unsigned long flags; + + spin_lock_irqsave(&tdc->lock, flags); + while (!list_empty(&tdc->cb_desc)) { + dma_desc = list_first_entry(&tdc->cb_desc, typeof(*dma_desc), + cb_node); + list_del(&dma_desc->cb_node); + dmaengine_desc_get_callback(&dma_desc->txd, &cb); + cb_count = dma_desc->cb_count; + dma_desc->cb_count = 0; + trace_tegra_dma_complete_cb(&tdc->dma_chan, cb_count, + cb.callback); + spin_unlock_irqrestore(&tdc->lock, flags); + while (cb_count--) + dmaengine_desc_callback_invoke(&cb, NULL); + spin_lock_irqsave(&tdc->lock, flags); + } + spin_unlock_irqrestore(&tdc->lock, flags); +} + +static irqreturn_t tegra_dma_isr(int irq, void *dev_id) +{ + struct tegra_dma_channel *tdc = dev_id; + u32 status; + + spin_lock(&tdc->lock); + + trace_tegra_dma_isr(&tdc->dma_chan, irq); + status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); + if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { + tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status); + tdc->isr_handler(tdc, false); + tasklet_schedule(&tdc->tasklet); + wake_up_all(&tdc->wq); + spin_unlock(&tdc->lock); + return IRQ_HANDLED; + } + + spin_unlock(&tdc->lock); + dev_info(tdc2dev(tdc), "Interrupt already served status 0x%08x\n", + status); + + return IRQ_NONE; +} + +static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *txd) +{ + struct tegra_dma_desc *dma_desc = txd_to_tegra_dma_desc(txd); + struct tegra_dma_channel *tdc = to_tegra_dma_chan(txd->chan); + unsigned long flags; + dma_cookie_t cookie; + + spin_lock_irqsave(&tdc->lock, flags); + dma_desc->dma_status = DMA_IN_PROGRESS; + cookie = dma_cookie_assign(&dma_desc->txd); + list_splice_tail_init(&dma_desc->tx_list, &tdc->pending_sg_req); + spin_unlock_irqrestore(&tdc->lock, flags); + + return cookie; +} + +static void tegra_dma_issue_pending(struct dma_chan *dc) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + unsigned long flags; + int err; + + spin_lock_irqsave(&tdc->lock, flags); + if (list_empty(&tdc->pending_sg_req)) { + dev_err(tdc2dev(tdc), "No DMA request\n"); + goto end; + } + if (!tdc->busy) { + err = pm_runtime_resume_and_get(tdc->tdma->dev); + if (err < 0) { + dev_err(tdc2dev(tdc), "Failed to enable DMA\n"); + goto end; + } + + tdc_start_head_req(tdc); + + /* Continuous single mode: Configure next req */ + if (tdc->cyclic) { + /* + * Wait for 1 burst time for configure DMA for + * next transfer. + */ + udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME); + tdc_configure_next_head_desc(tdc); + } + } +end: + spin_unlock_irqrestore(&tdc->lock, flags); +} + +static int tegra_dma_terminate_all(struct dma_chan *dc) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + struct tegra_dma_desc *dma_desc; + struct tegra_dma_sg_req *sgreq; + unsigned long flags; + u32 status, wcount; + bool was_busy; + + spin_lock_irqsave(&tdc->lock, flags); + + if (!tdc->busy) + goto skip_dma_stop; + + /* Pause DMA before checking the queue status */ + tegra_dma_pause(tdc, true); + + status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); + if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { + dev_dbg(tdc2dev(tdc), "%s():handling isr\n", __func__); + tdc->isr_handler(tdc, true); + status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); + } + if (tdc->tdma->chip_data->support_separate_wcount_reg) + wcount = tdc_read(tdc, TEGRA_APBDMA_CHAN_WORD_TRANSFER); + else + wcount = status; + + was_busy = tdc->busy; + tegra_dma_stop(tdc); + + if (!list_empty(&tdc->pending_sg_req) && was_busy) { + sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), + node); + sgreq->dma_desc->bytes_transferred += + get_current_xferred_count(tdc, sgreq, wcount); + } + tegra_dma_resume(tdc); + + pm_runtime_put(tdc->tdma->dev); + wake_up_all(&tdc->wq); + +skip_dma_stop: + tegra_dma_abort_all(tdc); + + while (!list_empty(&tdc->cb_desc)) { + dma_desc = list_first_entry(&tdc->cb_desc, typeof(*dma_desc), + cb_node); + list_del(&dma_desc->cb_node); + dma_desc->cb_count = 0; + } + spin_unlock_irqrestore(&tdc->lock, flags); + + return 0; +} + +static bool tegra_dma_eoc_interrupt_deasserted(struct tegra_dma_channel *tdc) +{ + unsigned long flags; + u32 status; + + spin_lock_irqsave(&tdc->lock, flags); + status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); + spin_unlock_irqrestore(&tdc->lock, flags); + + return !(status & TEGRA_APBDMA_STATUS_ISE_EOC); +} + +static void tegra_dma_synchronize(struct dma_chan *dc) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + int err; + + err = pm_runtime_resume_and_get(tdc->tdma->dev); + if (err < 0) { + dev_err(tdc2dev(tdc), "Failed to synchronize DMA: %d\n", err); + return; + } + + /* + * CPU, which handles interrupt, could be busy in + * uninterruptible state, in this case sibling CPU + * should wait until interrupt is handled. + */ + wait_event(tdc->wq, tegra_dma_eoc_interrupt_deasserted(tdc)); + + tasklet_kill(&tdc->tasklet); + + pm_runtime_put(tdc->tdma->dev); +} + +static unsigned int tegra_dma_sg_bytes_xferred(struct tegra_dma_channel *tdc, + struct tegra_dma_sg_req *sg_req) +{ + u32 status, wcount = 0; + + if (!list_is_first(&sg_req->node, &tdc->pending_sg_req)) + return 0; + + if (tdc->tdma->chip_data->support_separate_wcount_reg) + wcount = tdc_read(tdc, TEGRA_APBDMA_CHAN_WORD_TRANSFER); + + status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); + + if (!tdc->tdma->chip_data->support_separate_wcount_reg) + wcount = status; + + if (status & TEGRA_APBDMA_STATUS_ISE_EOC) + return sg_req->req_len; + + wcount = get_current_xferred_count(tdc, sg_req, wcount); + + if (!wcount) { + /* + * If wcount wasn't ever polled for this SG before, then + * simply assume that transfer hasn't started yet. + * + * Otherwise it's the end of the transfer. + * + * The alternative would be to poll the status register + * until EOC bit is set or wcount goes UP. That's so + * because EOC bit is getting set only after the last + * burst's completion and counter is less than the actual + * transfer size by 4 bytes. The counter value wraps around + * in a cyclic mode before EOC is set(!), so we can't easily + * distinguish start of transfer from its end. + */ + if (sg_req->words_xferred) + wcount = sg_req->req_len - 4; + + } else if (wcount < sg_req->words_xferred) { + /* + * This case will never happen for a non-cyclic transfer. + * + * For a cyclic transfer, although it is possible for the + * next transfer to have already started (resetting the word + * count), this case should still not happen because we should + * have detected that the EOC bit is set and hence the transfer + * was completed. + */ + WARN_ON_ONCE(1); + + wcount = sg_req->req_len - 4; + } else { + sg_req->words_xferred = wcount; + } + + return wcount; +} + +static enum dma_status tegra_dma_tx_status(struct dma_chan *dc, + dma_cookie_t cookie, + struct dma_tx_state *txstate) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + struct tegra_dma_desc *dma_desc; + struct tegra_dma_sg_req *sg_req; + enum dma_status ret; + unsigned long flags; + unsigned int residual; + unsigned int bytes = 0; + + ret = dma_cookie_status(dc, cookie, txstate); + if (ret == DMA_COMPLETE) + return ret; + + spin_lock_irqsave(&tdc->lock, flags); + + /* Check on wait_ack desc status */ + list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) { + if (dma_desc->txd.cookie == cookie) { + ret = dma_desc->dma_status; + goto found; + } + } + + /* Check in pending list */ + list_for_each_entry(sg_req, &tdc->pending_sg_req, node) { + dma_desc = sg_req->dma_desc; + if (dma_desc->txd.cookie == cookie) { + bytes = tegra_dma_sg_bytes_xferred(tdc, sg_req); + ret = dma_desc->dma_status; + goto found; + } + } + + dev_dbg(tdc2dev(tdc), "cookie %d not found\n", cookie); + dma_desc = NULL; + +found: + if (dma_desc && txstate) { + residual = dma_desc->bytes_requested - + ((dma_desc->bytes_transferred + bytes) % + dma_desc->bytes_requested); + dma_set_residue(txstate, residual); + } + + trace_tegra_dma_tx_status(&tdc->dma_chan, cookie, txstate); + spin_unlock_irqrestore(&tdc->lock, flags); + + return ret; +} + +static inline unsigned int get_bus_width(struct tegra_dma_channel *tdc, + enum dma_slave_buswidth slave_bw) +{ + switch (slave_bw) { + case DMA_SLAVE_BUSWIDTH_1_BYTE: + return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8; + case DMA_SLAVE_BUSWIDTH_2_BYTES: + return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16; + case DMA_SLAVE_BUSWIDTH_4_BYTES: + return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32; + case DMA_SLAVE_BUSWIDTH_8_BYTES: + return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64; + default: + dev_warn(tdc2dev(tdc), + "slave bw is not supported, using 32bits\n"); + return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32; + } +} + +static inline unsigned int get_burst_size(struct tegra_dma_channel *tdc, + u32 burst_size, + enum dma_slave_buswidth slave_bw, + u32 len) +{ + unsigned int burst_byte, burst_ahb_width; + + /* + * burst_size from client is in terms of the bus_width. + * convert them into AHB memory width which is 4 byte. + */ + burst_byte = burst_size * slave_bw; + burst_ahb_width = burst_byte / 4; + + /* If burst size is 0 then calculate the burst size based on length */ + if (!burst_ahb_width) { + if (len & 0xF) + return TEGRA_APBDMA_AHBSEQ_BURST_1; + else if ((len >> 4) & 0x1) + return TEGRA_APBDMA_AHBSEQ_BURST_4; + else + return TEGRA_APBDMA_AHBSEQ_BURST_8; + } + if (burst_ahb_width < 4) + return TEGRA_APBDMA_AHBSEQ_BURST_1; + else if (burst_ahb_width < 8) + return TEGRA_APBDMA_AHBSEQ_BURST_4; + else + return TEGRA_APBDMA_AHBSEQ_BURST_8; +} + +static int get_transfer_param(struct tegra_dma_channel *tdc, + enum dma_transfer_direction direction, + u32 *apb_addr, + u32 *apb_seq, + u32 *csr, + unsigned int *burst_size, + enum dma_slave_buswidth *slave_bw) +{ + switch (direction) { + case DMA_MEM_TO_DEV: + *apb_addr = tdc->dma_sconfig.dst_addr; + *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.dst_addr_width); + *burst_size = tdc->dma_sconfig.dst_maxburst; + *slave_bw = tdc->dma_sconfig.dst_addr_width; + *csr = TEGRA_APBDMA_CSR_DIR; + return 0; + + case DMA_DEV_TO_MEM: + *apb_addr = tdc->dma_sconfig.src_addr; + *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.src_addr_width); + *burst_size = tdc->dma_sconfig.src_maxburst; + *slave_bw = tdc->dma_sconfig.src_addr_width; + *csr = 0; + return 0; + + default: + dev_err(tdc2dev(tdc), "DMA direction is not supported\n"); + break; + } + + return -EINVAL; +} + +static void tegra_dma_prep_wcount(struct tegra_dma_channel *tdc, + struct tegra_dma_channel_regs *ch_regs, + u32 len) +{ + u32 len_field = (len - 4) & 0xFFFC; + + if (tdc->tdma->chip_data->support_separate_wcount_reg) + ch_regs->wcount = len_field; + else + ch_regs->csr |= len_field; +} + +static struct dma_async_tx_descriptor * +tegra_dma_prep_slave_sg(struct dma_chan *dc, + struct scatterlist *sgl, + unsigned int sg_len, + enum dma_transfer_direction direction, + unsigned long flags, + void *context) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + struct tegra_dma_sg_req *sg_req = NULL; + u32 csr, ahb_seq, apb_ptr, apb_seq; + enum dma_slave_buswidth slave_bw; + struct tegra_dma_desc *dma_desc; + struct list_head req_list; + struct scatterlist *sg; + unsigned int burst_size; + unsigned int i; + + if (!tdc->config_init) { + dev_err(tdc2dev(tdc), "DMA channel is not configured\n"); + return NULL; + } + if (sg_len < 1) { + dev_err(tdc2dev(tdc), "Invalid segment length %d\n", sg_len); + return NULL; + } + + if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr, + &burst_size, &slave_bw) < 0) + return NULL; + + INIT_LIST_HEAD(&req_list); + + ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB; + ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE << + TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT; + ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32; + + csr |= TEGRA_APBDMA_CSR_ONCE; + + if (tdc->slave_id != TEGRA_APBDMA_SLAVE_ID_INVALID) { + csr |= TEGRA_APBDMA_CSR_FLOW; + csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT; + } + + if (flags & DMA_PREP_INTERRUPT) { + csr |= TEGRA_APBDMA_CSR_IE_EOC; + } else { + WARN_ON_ONCE(1); + return NULL; + } + + apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1; + + dma_desc = tegra_dma_desc_get(tdc); + if (!dma_desc) { + dev_err(tdc2dev(tdc), "DMA descriptors not available\n"); + return NULL; + } + INIT_LIST_HEAD(&dma_desc->tx_list); + INIT_LIST_HEAD(&dma_desc->cb_node); + dma_desc->cb_count = 0; + dma_desc->bytes_requested = 0; + dma_desc->bytes_transferred = 0; + dma_desc->dma_status = DMA_IN_PROGRESS; + + /* Make transfer requests */ + for_each_sg(sgl, sg, sg_len, i) { + u32 len, mem; + + mem = sg_dma_address(sg); + len = sg_dma_len(sg); + + if ((len & 3) || (mem & 3) || + len > tdc->tdma->chip_data->max_dma_count) { + dev_err(tdc2dev(tdc), + "DMA length/memory address is not supported\n"); + tegra_dma_desc_put(tdc, dma_desc); + return NULL; + } + + sg_req = tegra_dma_sg_req_get(tdc); + if (!sg_req) { + dev_err(tdc2dev(tdc), "DMA sg-req not available\n"); + tegra_dma_desc_put(tdc, dma_desc); + return NULL; + } + + ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len); + dma_desc->bytes_requested += len; + + sg_req->ch_regs.apb_ptr = apb_ptr; + sg_req->ch_regs.ahb_ptr = mem; + sg_req->ch_regs.csr = csr; + tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len); + sg_req->ch_regs.apb_seq = apb_seq; + sg_req->ch_regs.ahb_seq = ahb_seq; + sg_req->configured = false; + sg_req->last_sg = false; + sg_req->dma_desc = dma_desc; + sg_req->req_len = len; + + list_add_tail(&sg_req->node, &dma_desc->tx_list); + } + sg_req->last_sg = true; + if (flags & DMA_CTRL_ACK) + dma_desc->txd.flags = DMA_CTRL_ACK; + + /* + * Make sure that mode should not be conflicting with currently + * configured mode. + */ + if (!tdc->isr_handler) { + tdc->isr_handler = handle_once_dma_done; + tdc->cyclic = false; + } else { + if (tdc->cyclic) { + dev_err(tdc2dev(tdc), "DMA configured in cyclic mode\n"); + tegra_dma_desc_put(tdc, dma_desc); + return NULL; + } + } + + return &dma_desc->txd; +} + +static struct dma_async_tx_descriptor * +tegra_dma_prep_dma_cyclic(struct dma_chan *dc, dma_addr_t buf_addr, + size_t buf_len, + size_t period_len, + enum dma_transfer_direction direction, + unsigned long flags) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + struct tegra_dma_sg_req *sg_req = NULL; + u32 csr, ahb_seq, apb_ptr, apb_seq; + enum dma_slave_buswidth slave_bw; + struct tegra_dma_desc *dma_desc; + dma_addr_t mem = buf_addr; + unsigned int burst_size; + size_t len, remain_len; + + if (!buf_len || !period_len) { + dev_err(tdc2dev(tdc), "Invalid buffer/period len\n"); + return NULL; + } + + if (!tdc->config_init) { + dev_err(tdc2dev(tdc), "DMA slave is not configured\n"); + return NULL; + } + + /* + * We allow to take more number of requests till DMA is + * not started. The driver will loop over all requests. + * Once DMA is started then new requests can be queued only after + * terminating the DMA. + */ + if (tdc->busy) { + dev_err(tdc2dev(tdc), "Request not allowed when DMA running\n"); + return NULL; + } + + /* + * We only support cycle transfer when buf_len is multiple of + * period_len. + */ + if (buf_len % period_len) { + dev_err(tdc2dev(tdc), "buf_len is not multiple of period_len\n"); + return NULL; + } + + len = period_len; + if ((len & 3) || (buf_addr & 3) || + len > tdc->tdma->chip_data->max_dma_count) { + dev_err(tdc2dev(tdc), "Req len/mem address is not correct\n"); + return NULL; + } + + if (get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr, + &burst_size, &slave_bw) < 0) + return NULL; + + ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB; + ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE << + TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT; + ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32; + + if (tdc->slave_id != TEGRA_APBDMA_SLAVE_ID_INVALID) { + csr |= TEGRA_APBDMA_CSR_FLOW; + csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT; + } + + if (flags & DMA_PREP_INTERRUPT) { + csr |= TEGRA_APBDMA_CSR_IE_EOC; + } else { + WARN_ON_ONCE(1); + return NULL; + } + + apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1; + + dma_desc = tegra_dma_desc_get(tdc); + if (!dma_desc) { + dev_err(tdc2dev(tdc), "not enough descriptors available\n"); + return NULL; + } + + INIT_LIST_HEAD(&dma_desc->tx_list); + INIT_LIST_HEAD(&dma_desc->cb_node); + dma_desc->cb_count = 0; + + dma_desc->bytes_transferred = 0; + dma_desc->bytes_requested = buf_len; + remain_len = buf_len; + + /* Split transfer equal to period size */ + while (remain_len) { + sg_req = tegra_dma_sg_req_get(tdc); + if (!sg_req) { + dev_err(tdc2dev(tdc), "DMA sg-req not available\n"); + tegra_dma_desc_put(tdc, dma_desc); + return NULL; + } + + ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len); + sg_req->ch_regs.apb_ptr = apb_ptr; + sg_req->ch_regs.ahb_ptr = mem; + sg_req->ch_regs.csr = csr; + tegra_dma_prep_wcount(tdc, &sg_req->ch_regs, len); + sg_req->ch_regs.apb_seq = apb_seq; + sg_req->ch_regs.ahb_seq = ahb_seq; + sg_req->configured = false; + sg_req->last_sg = false; + sg_req->dma_desc = dma_desc; + sg_req->req_len = len; + + list_add_tail(&sg_req->node, &dma_desc->tx_list); + remain_len -= len; + mem += len; + } + sg_req->last_sg = true; + if (flags & DMA_CTRL_ACK) + dma_desc->txd.flags = DMA_CTRL_ACK; + + /* + * Make sure that mode should not be conflicting with currently + * configured mode. + */ + if (!tdc->isr_handler) { + tdc->isr_handler = handle_cont_sngl_cycle_dma_done; + tdc->cyclic = true; + } else { + if (!tdc->cyclic) { + dev_err(tdc2dev(tdc), "DMA configuration conflict\n"); + tegra_dma_desc_put(tdc, dma_desc); + return NULL; + } + } + + return &dma_desc->txd; +} + +static int tegra_dma_alloc_chan_resources(struct dma_chan *dc) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + + dma_cookie_init(&tdc->dma_chan); + + return 0; +} + +static void tegra_dma_free_chan_resources(struct dma_chan *dc) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + struct tegra_dma_desc *dma_desc; + struct tegra_dma_sg_req *sg_req; + struct list_head dma_desc_list; + struct list_head sg_req_list; + + INIT_LIST_HEAD(&dma_desc_list); + INIT_LIST_HEAD(&sg_req_list); + + dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id); + + tegra_dma_terminate_all(dc); + tasklet_kill(&tdc->tasklet); + + list_splice_init(&tdc->pending_sg_req, &sg_req_list); + list_splice_init(&tdc->free_sg_req, &sg_req_list); + list_splice_init(&tdc->free_dma_desc, &dma_desc_list); + INIT_LIST_HEAD(&tdc->cb_desc); + tdc->config_init = false; + tdc->isr_handler = NULL; + + while (!list_empty(&dma_desc_list)) { + dma_desc = list_first_entry(&dma_desc_list, typeof(*dma_desc), + node); + list_del(&dma_desc->node); + kfree(dma_desc); + } + + while (!list_empty(&sg_req_list)) { + sg_req = list_first_entry(&sg_req_list, typeof(*sg_req), node); + list_del(&sg_req->node); + kfree(sg_req); + } + + tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID; +} + +static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct tegra_dma *tdma = ofdma->of_dma_data; + struct tegra_dma_channel *tdc; + struct dma_chan *chan; + + if (dma_spec->args[0] > TEGRA_APBDMA_CSR_REQ_SEL_MASK) { + dev_err(tdma->dev, "Invalid slave id: %d\n", dma_spec->args[0]); + return NULL; + } + + chan = dma_get_any_slave_channel(&tdma->dma_dev); + if (!chan) + return NULL; + + tdc = to_tegra_dma_chan(chan); + tdc->slave_id = dma_spec->args[0]; + + return chan; +} + +/* Tegra20 specific DMA controller information */ +static const struct tegra_dma_chip_data tegra20_dma_chip_data = { + .nr_channels = 16, + .channel_reg_size = 0x20, + .max_dma_count = 1024UL * 64, + .support_channel_pause = false, + .support_separate_wcount_reg = false, +}; + +/* Tegra30 specific DMA controller information */ +static const struct tegra_dma_chip_data tegra30_dma_chip_data = { + .nr_channels = 32, + .channel_reg_size = 0x20, + .max_dma_count = 1024UL * 64, + .support_channel_pause = false, + .support_separate_wcount_reg = false, +}; + +/* Tegra114 specific DMA controller information */ +static const struct tegra_dma_chip_data tegra114_dma_chip_data = { + .nr_channels = 32, + .channel_reg_size = 0x20, + .max_dma_count = 1024UL * 64, + .support_channel_pause = true, + .support_separate_wcount_reg = false, +}; + +/* Tegra148 specific DMA controller information */ +static const struct tegra_dma_chip_data tegra148_dma_chip_data = { + .nr_channels = 32, + .channel_reg_size = 0x40, + .max_dma_count = 1024UL * 64, + .support_channel_pause = true, + .support_separate_wcount_reg = true, +}; + +static int tegra_dma_init_hw(struct tegra_dma *tdma) +{ + int err; + + err = reset_control_assert(tdma->rst); + if (err) { + dev_err(tdma->dev, "failed to assert reset: %d\n", err); + return err; + } + + err = clk_enable(tdma->dma_clk); + if (err) { + dev_err(tdma->dev, "failed to enable clk: %d\n", err); + return err; + } + + /* reset DMA controller */ + udelay(2); + reset_control_deassert(tdma->rst); + + /* enable global DMA registers */ + tdma_write(tdma, TEGRA_APBDMA_GENERAL, TEGRA_APBDMA_GENERAL_ENABLE); + tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0); + tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFF); + + clk_disable(tdma->dma_clk); + + return 0; +} + +static int tegra_dma_probe(struct platform_device *pdev) +{ + const struct tegra_dma_chip_data *cdata; + struct tegra_dma *tdma; + unsigned int i; + size_t size; + int ret; + + cdata = of_device_get_match_data(&pdev->dev); + size = struct_size(tdma, channels, cdata->nr_channels); + + tdma = devm_kzalloc(&pdev->dev, size, GFP_KERNEL); + if (!tdma) + return -ENOMEM; + + tdma->dev = &pdev->dev; + tdma->chip_data = cdata; + platform_set_drvdata(pdev, tdma); + + tdma->base_addr = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(tdma->base_addr)) + return PTR_ERR(tdma->base_addr); + + tdma->dma_clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(tdma->dma_clk)) { + dev_err(&pdev->dev, "Error: Missing controller clock\n"); + return PTR_ERR(tdma->dma_clk); + } + + tdma->rst = devm_reset_control_get(&pdev->dev, "dma"); + if (IS_ERR(tdma->rst)) { + dev_err(&pdev->dev, "Error: Missing reset\n"); + return PTR_ERR(tdma->rst); + } + + spin_lock_init(&tdma->global_lock); + + ret = clk_prepare(tdma->dma_clk); + if (ret) + return ret; + + ret = tegra_dma_init_hw(tdma); + if (ret) + goto err_clk_unprepare; + + pm_runtime_irq_safe(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + INIT_LIST_HEAD(&tdma->dma_dev.channels); + for (i = 0; i < cdata->nr_channels; i++) { + struct tegra_dma_channel *tdc = &tdma->channels[i]; + int irq; + + tdc->chan_addr = tdma->base_addr + + TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET + + (i * cdata->channel_reg_size); + + irq = platform_get_irq(pdev, i); + if (irq < 0) { + ret = irq; + goto err_pm_disable; + } + + snprintf(tdc->name, sizeof(tdc->name), "apbdma.%d", i); + ret = devm_request_irq(&pdev->dev, irq, tegra_dma_isr, 0, + tdc->name, tdc); + if (ret) { + dev_err(&pdev->dev, + "request_irq failed with err %d channel %d\n", + ret, i); + goto err_pm_disable; + } + + tdc->dma_chan.device = &tdma->dma_dev; + dma_cookie_init(&tdc->dma_chan); + list_add_tail(&tdc->dma_chan.device_node, + &tdma->dma_dev.channels); + tdc->tdma = tdma; + tdc->id = i; + tdc->slave_id = TEGRA_APBDMA_SLAVE_ID_INVALID; + + tasklet_setup(&tdc->tasklet, tegra_dma_tasklet); + spin_lock_init(&tdc->lock); + init_waitqueue_head(&tdc->wq); + + INIT_LIST_HEAD(&tdc->pending_sg_req); + INIT_LIST_HEAD(&tdc->free_sg_req); + INIT_LIST_HEAD(&tdc->free_dma_desc); + INIT_LIST_HEAD(&tdc->cb_desc); + } + + dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask); + dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask); + dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask); + + tdma->global_pause_count = 0; + tdma->dma_dev.dev = &pdev->dev; + tdma->dma_dev.device_alloc_chan_resources = + tegra_dma_alloc_chan_resources; + tdma->dma_dev.device_free_chan_resources = + tegra_dma_free_chan_resources; + tdma->dma_dev.device_prep_slave_sg = tegra_dma_prep_slave_sg; + tdma->dma_dev.device_prep_dma_cyclic = tegra_dma_prep_dma_cyclic; + tdma->dma_dev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | + BIT(DMA_SLAVE_BUSWIDTH_8_BYTES); + tdma->dma_dev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | + BIT(DMA_SLAVE_BUSWIDTH_8_BYTES); + tdma->dma_dev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); + tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; + tdma->dma_dev.device_config = tegra_dma_slave_config; + tdma->dma_dev.device_terminate_all = tegra_dma_terminate_all; + tdma->dma_dev.device_synchronize = tegra_dma_synchronize; + tdma->dma_dev.device_tx_status = tegra_dma_tx_status; + tdma->dma_dev.device_issue_pending = tegra_dma_issue_pending; + + ret = dma_async_device_register(&tdma->dma_dev); + if (ret < 0) { + dev_err(&pdev->dev, + "Tegra20 APB DMA driver registration failed %d\n", ret); + goto err_pm_disable; + } + + ret = of_dma_controller_register(pdev->dev.of_node, + tegra_dma_of_xlate, tdma); + if (ret < 0) { + dev_err(&pdev->dev, + "Tegra20 APB DMA OF registration failed %d\n", ret); + goto err_unregister_dma_dev; + } + + dev_info(&pdev->dev, "Tegra20 APB DMA driver registered %u channels\n", + cdata->nr_channels); + + return 0; + +err_unregister_dma_dev: + dma_async_device_unregister(&tdma->dma_dev); + +err_pm_disable: + pm_runtime_disable(&pdev->dev); + +err_clk_unprepare: + clk_unprepare(tdma->dma_clk); + + return ret; +} + +static int tegra_dma_remove(struct platform_device *pdev) +{ + struct tegra_dma *tdma = platform_get_drvdata(pdev); + + of_dma_controller_free(pdev->dev.of_node); + dma_async_device_unregister(&tdma->dma_dev); + pm_runtime_disable(&pdev->dev); + clk_unprepare(tdma->dma_clk); + + return 0; +} + +static int __maybe_unused tegra_dma_runtime_suspend(struct device *dev) +{ + struct tegra_dma *tdma = dev_get_drvdata(dev); + + clk_disable(tdma->dma_clk); + + return 0; +} + +static int __maybe_unused tegra_dma_runtime_resume(struct device *dev) +{ + struct tegra_dma *tdma = dev_get_drvdata(dev); + + return clk_enable(tdma->dma_clk); +} + +static int __maybe_unused tegra_dma_dev_suspend(struct device *dev) +{ + struct tegra_dma *tdma = dev_get_drvdata(dev); + unsigned long flags; + unsigned int i; + bool busy; + + for (i = 0; i < tdma->chip_data->nr_channels; i++) { + struct tegra_dma_channel *tdc = &tdma->channels[i]; + + tasklet_kill(&tdc->tasklet); + + spin_lock_irqsave(&tdc->lock, flags); + busy = tdc->busy; + spin_unlock_irqrestore(&tdc->lock, flags); + + if (busy) { + dev_err(tdma->dev, "channel %u busy\n", i); + return -EBUSY; + } + } + + return pm_runtime_force_suspend(dev); +} + +static int __maybe_unused tegra_dma_dev_resume(struct device *dev) +{ + struct tegra_dma *tdma = dev_get_drvdata(dev); + int err; + + err = tegra_dma_init_hw(tdma); + if (err) + return err; + + return pm_runtime_force_resume(dev); +} + +static const struct dev_pm_ops tegra_dma_dev_pm_ops = { + SET_RUNTIME_PM_OPS(tegra_dma_runtime_suspend, tegra_dma_runtime_resume, + NULL) + SET_SYSTEM_SLEEP_PM_OPS(tegra_dma_dev_suspend, tegra_dma_dev_resume) +}; + +static const struct of_device_id tegra_dma_of_match[] = { + { + .compatible = "nvidia,tegra148-apbdma", + .data = &tegra148_dma_chip_data, + }, { + .compatible = "nvidia,tegra114-apbdma", + .data = &tegra114_dma_chip_data, + }, { + .compatible = "nvidia,tegra30-apbdma", + .data = &tegra30_dma_chip_data, + }, { + .compatible = "nvidia,tegra20-apbdma", + .data = &tegra20_dma_chip_data, + }, { + }, +}; +MODULE_DEVICE_TABLE(of, tegra_dma_of_match); + +static struct platform_driver tegra_dmac_driver = { + .driver = { + .name = "tegra-apbdma", + .pm = &tegra_dma_dev_pm_ops, + .of_match_table = tegra_dma_of_match, + }, + .probe = tegra_dma_probe, + .remove = tegra_dma_remove, +}; + +module_platform_driver(tegra_dmac_driver); + +MODULE_DESCRIPTION("NVIDIA Tegra APB DMA Controller driver"); +MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); +MODULE_LICENSE("GPL v2"); |