--- /dev/null
+/*
+ * DMA driver for Nvidia's Tegra20 APB DMA controller.
+ *
+ * Copyright (c) 2012-2013, NVIDIA CORPORATION. All rights reserved.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#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_device.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 "dmaengine.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_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 (1 << 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
+
+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 {
+ int nr_channels;
+ int channel_reg_size;
+ int max_dma_count;
+ bool support_channel_pause;
+ bool support_separate_wcount_reg;
+};
+
+/* DMA channel registers */
+struct tegra_dma_channel_regs {
+ unsigned long csr;
+ unsigned long ahb_ptr;
+ unsigned long apb_ptr;
+ unsigned long ahb_seq;
+ unsigned long apb_seq;
+ unsigned long 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;
+ int req_len;
+ bool configured;
+ bool last_sg;
+ bool half_done;
+ struct list_head node;
+ struct tegra_dma_desc *dma_desc;
+};
+
+/*
+ * 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;
+ int bytes_requested;
+ int bytes_transferred;
+ enum dma_status dma_status;
+ struct list_head node;
+ struct list_head tx_list;
+ struct list_head cb_node;
+ 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[30];
+ bool config_init;
+ int id;
+ int irq;
+ unsigned long chan_base_offset;
+ 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;
+ dma_async_tx_callback callback;
+ void *callback_param;
+
+ /* Channel-slave specific configuration */
+ unsigned int slave_id;
+ struct dma_slave_config dma_sconfig;
+ struct tegra_dma_channel_regs channel_reg;
+};
+
+/* 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;
+
+ /* Some register need to be cache before suspend */
+ u32 reg_gen;
+
+ /* Last member of the structure */
+ struct tegra_dma_channel channels[0];
+};
+
+static inline void tdma_write(struct tegra_dma *tdma, u32 reg, u32 val)
+{
+ writel(val, tdma->base_addr + reg);
+}
+
+static inline u32 tdma_read(struct tegra_dma *tdma, u32 reg)
+{
+ return readl(tdma->base_addr + reg);
+}
+
+static inline void tdc_write(struct tegra_dma_channel *tdc,
+ u32 reg, u32 val)
+{
+ writel(val, tdc->tdma->base_addr + tdc->chan_base_offset + reg);
+}
+
+static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg)
+{
+ return readl(tdc->tdma->base_addr + tdc->chan_base_offset + 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);
+static int tegra_dma_runtime_suspend(struct device *dev);
+static int tegra_dma_runtime_resume(struct device *dev);
+
+/* 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)) {
+ 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_ATOMIC);
+ if (!dma_desc) {
+ dev_err(tdc2dev(tdc), "dma_desc alloc failed\n");
+ 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 = NULL;
+ 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(struct tegra_dma_sg_req), GFP_ATOMIC);
+ if (!sg_req)
+ dev_err(tdc2dev(tdc), "sg_req alloc failed\n");
+ 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));
+ if (!tdc->slave_id)
+ tdc->slave_id = sconfig->slave_id;
+ 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);
+ tdma_write(tdma, TEGRA_APBDMA_GENERAL, 0);
+ if (wait_for_burst_complete)
+ udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME);
+}
+
+static void tegra_dma_global_resume(struct tegra_dma_channel *tdc)
+{
+ struct tegra_dma *tdma = tdc->tdma;
+
+ tdma_write(tdma, TEGRA_APBDMA_GENERAL, TEGRA_APBDMA_GENERAL_ENABLE);
+ 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;
+ u32 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;
+
+ tegra_dma_resume(tdc);
+}
+
+static void tdc_start_head_req(struct tegra_dma_channel *tdc)
+{
+ struct tegra_dma_sg_req *sg_req;
+
+ if (list_empty(&tdc->pending_sg_req))
+ return;
+
+ sg_req = list_first_entry(&tdc->pending_sg_req,
+ typeof(*sg_req), node);
+ tegra_dma_start(tdc, sg_req);
+ sg_req->configured = true;
+ tdc->busy = true;
+}
+
+static void tdc_configure_next_head_desc(struct tegra_dma_channel *tdc)
+{
+ struct tegra_dma_sg_req *hsgreq;
+ struct tegra_dma_sg_req *hnsgreq;
+
+ if (list_empty(&tdc->pending_sg_req))
+ return;
+
+ 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 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_sg_req *sgreq;
+ struct tegra_dma_desc *dma_desc;
+
+ 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,
+ struct tegra_dma_sg_req *last_sg_req, bool to_terminate)
+{
+ struct tegra_dma_sg_req *hsgreq = NULL;
+
+ if (list_empty(&tdc->pending_sg_req)) {
+ dev_err(tdc2dev(tdc), "Dma is running without req\n");
+ tegra_dma_stop(tdc);
+ return false;
+ }
+
+ /*
+ * 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);
+ dev_err(tdc2dev(tdc), "Error in dma transfer, 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_sg_req *sgreq;
+ struct tegra_dma_desc *dma_desc;
+
+ 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 || list_empty(&tdc->pending_sg_req))
+ return;
+
+ tdc_start_head_req(tdc);
+ return;
+}
+
+static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc,
+ bool to_terminate)
+{
+ struct tegra_dma_sg_req *sgreq;
+ struct tegra_dma_desc *dma_desc;
+ bool st;
+
+ sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node);
+ dma_desc = sgreq->dma_desc;
+ dma_desc->bytes_transferred += sgreq->req_len;
+
+ /* Callback need to be call */
+ if (!dma_desc->cb_count)
+ list_add_tail(&dma_desc->cb_node, &tdc->cb_desc);
+ dma_desc->cb_count++;
+
+ /* 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, sgreq, to_terminate);
+ if (!st)
+ dma_desc->dma_status = DMA_ERROR;
+ }
+ return;
+}
+
+static void tegra_dma_tasklet(unsigned long data)
+{
+ struct tegra_dma_channel *tdc = (struct tegra_dma_channel *)data;
+ dma_async_tx_callback callback = NULL;
+ void *callback_param = NULL;
+ struct tegra_dma_desc *dma_desc;
+ unsigned long flags;
+ int cb_count;
+
+ 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);
+ callback = dma_desc->txd.callback;
+ callback_param = dma_desc->txd.callback_param;
+ cb_count = dma_desc->cb_count;
+ dma_desc->cb_count = 0;
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ while (cb_count-- && callback)
+ callback(callback_param);
+ 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;
+ unsigned long status;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tdc->lock, flags);
+
+ 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);
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ return IRQ_HANDLED;
+ }
+
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ dev_info(tdc2dev(tdc),
+ "Interrupt already served status 0x%08lx\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;
+
+ 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) {
+ 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);
+ return;
+}
+
+static int tegra_dma_terminate_all(struct dma_chan *dc)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ struct tegra_dma_sg_req *sgreq;
+ struct tegra_dma_desc *dma_desc;
+ unsigned long flags;
+ unsigned long status;
+ unsigned long wcount;
+ bool was_busy;
+
+ spin_lock_irqsave(&tdc->lock, flags);
+ if (list_empty(&tdc->pending_sg_req)) {
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ return 0;
+ }
+
+ 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);
+
+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 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;
+
+ 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) {
+ residual = dma_desc->bytes_requested -
+ (dma_desc->bytes_transferred %
+ dma_desc->bytes_requested);
+ dma_set_residue(txstate, residual);
+ ret = dma_desc->dma_status;
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ return ret;
+ }
+ }
+
+ /* 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) {
+ residual = dma_desc->bytes_requested -
+ (dma_desc->bytes_transferred %
+ dma_desc->bytes_requested);
+ dma_set_residue(txstate, residual);
+ ret = dma_desc->dma_status;
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ return ret;
+ }
+ }
+
+ dev_dbg(tdc2dev(tdc), "cookie %d does not found\n", cookie);
+ spin_unlock_irqrestore(&tdc->lock, flags);
+ return ret;
+}
+
+static inline 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 int get_burst_size(struct tegra_dma_channel *tdc,
+ u32 burst_size, enum dma_slave_buswidth slave_bw, int len)
+{
+ int burst_byte;
+ int 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, unsigned long *apb_addr,
+ unsigned long *apb_seq, unsigned long *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");
+ return -EINVAL;
+ }
+ 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_desc *dma_desc;
+ unsigned int i;
+ struct scatterlist *sg;
+ unsigned long csr, ahb_seq, apb_ptr, apb_seq;
+ struct list_head req_list;
+ struct tegra_dma_sg_req *sg_req = NULL;
+ u32 burst_size;
+ enum dma_slave_buswidth slave_bw;
+ int ret;
+
+ 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;
+ }
+
+ ret = get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr,
+ &burst_size, &slave_bw);
+ if (ret < 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 | 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;
+
+ 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_desc *dma_desc = NULL;
+ struct tegra_dma_sg_req *sg_req = NULL;
+ unsigned long csr, ahb_seq, apb_ptr, apb_seq;
+ int len;
+ size_t remain_len;
+ dma_addr_t mem = buf_addr;
+ u32 burst_size;
+ enum dma_slave_buswidth slave_bw;
+ int ret;
+
+ 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;
+ }
+
+ ret = get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr,
+ &burst_size, &slave_bw);
+ if (ret < 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;
+
+ csr |= TEGRA_APBDMA_CSR_FLOW;
+ if (flags & DMA_PREP_INTERRUPT)
+ csr |= TEGRA_APBDMA_CSR_IE_EOC;
+ csr |= tdc->slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT;
+
+ 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->half_done = 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);
+ struct tegra_dma *tdma = tdc->tdma;
+ int ret;
+
+ dma_cookie_init(&tdc->dma_chan);
+ tdc->config_init = false;
+ ret = clk_prepare_enable(tdma->dma_clk);
+ if (ret < 0)
+ dev_err(tdc2dev(tdc), "clk_prepare_enable failed: %d\n", ret);
+ return ret;
+}
+
+static void tegra_dma_free_chan_resources(struct dma_chan *dc)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ struct tegra_dma *tdma = tdc->tdma;
+
+ 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;
+ unsigned long flags;
+
+ INIT_LIST_HEAD(&dma_desc_list);
+ INIT_LIST_HEAD(&sg_req_list);
+
+ dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id);
+
+ if (tdc->busy)
+ tegra_dma_terminate_all(dc);
+
+ spin_lock_irqsave(&tdc->lock, flags);
+ 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;
+ spin_unlock_irqrestore(&tdc->lock, flags);
+
+ 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);
+ }
+ clk_disable_unprepare(tdma->dma_clk);
+
+ tdc->slave_id = 0;
+}
+
+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 dma_chan *chan;
+ struct tegra_dma_channel *tdc;
+
+ 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 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 int tegra_dma_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct tegra_dma *tdma;
+ int ret;
+ int i;
+ const struct tegra_dma_chip_data *cdata = NULL;
+ const struct of_device_id *match;
+
+ match = of_match_device(tegra_dma_of_match, &pdev->dev);
+ if (!match) {
+ dev_err(&pdev->dev, "Error: No device match found\n");
+ return -ENODEV;
+ }
+ cdata = match->data;
+
+ tdma = devm_kzalloc(&pdev->dev, sizeof(*tdma) + cdata->nr_channels *
+ sizeof(struct tegra_dma_channel), GFP_KERNEL);
+ if (!tdma) {
+ dev_err(&pdev->dev, "Error: memory allocation failed\n");
+ return -ENOMEM;
+ }
+
+ tdma->dev = &pdev->dev;
+ tdma->chip_data = cdata;
+ platform_set_drvdata(pdev, tdma);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ tdma->base_addr = devm_ioremap_resource(&pdev->dev, res);
+ 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);
+
+ pm_runtime_enable(&pdev->dev);
+ if (!pm_runtime_enabled(&pdev->dev)) {
+ ret = tegra_dma_runtime_resume(&pdev->dev);
+ if (ret) {
+ dev_err(&pdev->dev, "dma_runtime_resume failed %d\n",
+ ret);
+ goto err_pm_disable;
+ }
+ }
+
+ /* Enable clock before accessing registers */
+ ret = clk_prepare_enable(tdma->dma_clk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "clk_prepare_enable failed: %d\n", ret);
+ goto err_pm_disable;
+ }
+
+ /* Reset DMA controller */
+ reset_control_assert(tdma->rst);
+ 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, 0xFFFFFFFFul);
+
+ clk_disable_unprepare(tdma->dma_clk);
+
+ INIT_LIST_HEAD(&tdma->dma_dev.channels);
+ for (i = 0; i < cdata->nr_channels; i++) {
+ struct tegra_dma_channel *tdc = &tdma->channels[i];
+
+ tdc->chan_base_offset = TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET +
+ i * cdata->channel_reg_size;
+
+ res = platform_get_resource(pdev, IORESOURCE_IRQ, i);
+ if (!res) {
+ ret = -EINVAL;
+ dev_err(&pdev->dev, "No irq resource for chan %d\n", i);
+ goto err_irq;
+ }
+ tdc->irq = res->start;
+ snprintf(tdc->name, sizeof(tdc->name), "apbdma.%d", i);
+ ret = devm_request_irq(&pdev->dev, tdc->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_irq;
+ }
+
+ 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;
+
+ tasklet_init(&tdc->tasklet, tegra_dma_tasklet,
+ (unsigned long)tdc);
+ spin_lock_init(&tdc->lock);
+
+ 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->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);
+ /*
+ * XXX The hardware appears to support
+ * DMA_RESIDUE_GRANULARITY_BURST-level reporting, but it's
+ * only used by this driver during tegra_dma_terminate_all()
+ */
+ tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
+ tdma->dma_dev.device_config = tegra_dma_slave_config;
+ tdma->dma_dev.device_terminate_all = tegra_dma_terminate_all;
+ 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_irq;
+ }
+
+ 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 register %d channels\n",
+ cdata->nr_channels);
+ return 0;
+
+err_unregister_dma_dev:
+ dma_async_device_unregister(&tdma->dma_dev);
+err_irq:
+ while (--i >= 0) {
+ struct tegra_dma_channel *tdc = &tdma->channels[i];
+ tasklet_kill(&tdc->tasklet);
+ }
+
+err_pm_disable:
+ pm_runtime_disable(&pdev->dev);
+ if (!pm_runtime_status_suspended(&pdev->dev))
+ tegra_dma_runtime_suspend(&pdev->dev);
+ return ret;
+}
+
+static int tegra_dma_remove(struct platform_device *pdev)
+{
+ struct tegra_dma *tdma = platform_get_drvdata(pdev);
+ int i;
+ struct tegra_dma_channel *tdc;
+
+ dma_async_device_unregister(&tdma->dma_dev);
+
+ for (i = 0; i < tdma->chip_data->nr_channels; ++i) {
+ tdc = &tdma->channels[i];
+ tasklet_kill(&tdc->tasklet);
+ }
+
+ pm_runtime_disable(&pdev->dev);
+ if (!pm_runtime_status_suspended(&pdev->dev))
+ tegra_dma_runtime_suspend(&pdev->dev);
+
+ return 0;
+}
+
+static int tegra_dma_runtime_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct tegra_dma *tdma = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(tdma->dma_clk);
+ return 0;
+}
+
+static int tegra_dma_runtime_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct tegra_dma *tdma = platform_get_drvdata(pdev);
+ int ret;
+
+ ret = clk_prepare_enable(tdma->dma_clk);
+ if (ret < 0) {
+ dev_err(dev, "clk_enable failed: %d\n", ret);
+ return ret;
+ }
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int tegra_dma_pm_suspend(struct device *dev)
+{
+ struct tegra_dma *tdma = dev_get_drvdata(dev);
+ int i;
+ int ret;
+
+ /* Enable clock before accessing register */
+ ret = tegra_dma_runtime_resume(dev);
+ if (ret < 0)
+ return ret;
+
+ tdma->reg_gen = tdma_read(tdma, TEGRA_APBDMA_GENERAL);
+ for (i = 0; i < tdma->chip_data->nr_channels; i++) {
+ struct tegra_dma_channel *tdc = &tdma->channels[i];
+ struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg;
+
+ ch_reg->csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR);
+ ch_reg->ahb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBPTR);
+ ch_reg->apb_ptr = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBPTR);
+ ch_reg->ahb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_AHBSEQ);
+ ch_reg->apb_seq = tdc_read(tdc, TEGRA_APBDMA_CHAN_APBSEQ);
+ }
+
+ /* Disable clock */
+ tegra_dma_runtime_suspend(dev);
+ return 0;
+}
+
+static int tegra_dma_pm_resume(struct device *dev)
+{
+ struct tegra_dma *tdma = dev_get_drvdata(dev);
+ int i;
+ int ret;
+
+ /* Enable clock before accessing register */
+ ret = tegra_dma_runtime_resume(dev);
+ if (ret < 0)
+ return ret;
+
+ tdma_write(tdma, TEGRA_APBDMA_GENERAL, tdma->reg_gen);
+ tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0);
+ tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul);
+
+ for (i = 0; i < tdma->chip_data->nr_channels; i++) {
+ struct tegra_dma_channel *tdc = &tdma->channels[i];
+ struct tegra_dma_channel_regs *ch_reg = &tdc->channel_reg;
+
+ tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_reg->apb_seq);
+ tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_reg->apb_ptr);
+ tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_reg->ahb_seq);
+ tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_reg->ahb_ptr);
+ tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR,
+ (ch_reg->csr & ~TEGRA_APBDMA_CSR_ENB));
+ }
+
+ /* Disable clock */
+ tegra_dma_runtime_suspend(dev);
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops tegra_dma_dev_pm_ops = {
+#ifdef CONFIG_PM
+ .runtime_suspend = tegra_dma_runtime_suspend,
+ .runtime_resume = tegra_dma_runtime_resume,
+#endif
+ SET_SYSTEM_SLEEP_PM_OPS(tegra_dma_pm_suspend, tegra_dma_pm_resume)
+};
+
+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_ALIAS("platform:tegra20-apbdma");
+MODULE_DESCRIPTION("NVIDIA Tegra APB DMA Controller driver");
+MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
+MODULE_LICENSE("GPL v2");
Code Review / kvmfornfv.git / blobdiff