[Patch v1 2/4] dma: tegra: Adding Tegra GPC DMA controller driver

Rajesh Gumasta
2020-07-20T06:34:46Z

v4 changes: Removed pending dma desc list and other unused
data structures

v3 changes: Removed free list for dma_desc and sg

Adding GPC DMA controller driver for Tegra186 and Tegra194. The driver
supports dma transfers between memory to memory, IO to memory and
memory to IO.

Signed-off-by: Pavan Kunapuli <pkunapuli@nvidia.com>
Signed-off-by: Rajesh Gumasta <rgumasta@nvidia.com>
---
drivers/dma/Kconfig | 12 +
drivers/dma/Makefile | 1 +
drivers/dma/tegra-gpc-dma.c | 1512 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 1525 insertions(+)
create mode 100644 drivers/dma/tegra-gpc-dma.c

diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index e9ed916..be4c395 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -639,6 +639,18 @@ config TEGRA210_ADMA
peripheral and vice versa. It does not support memory to
memory data transfer.

+config TEGRA_GPC_DMA
+ tristate "NVIDIA Tegra GPC DMA support"
+ depends on ARCH_TEGRA_186_SOC || ARCH_TEGRA_194_SOC || COMPILE_TEST
+ select DMA_ENGINE
+ help
+ Support for the NVIDIA Tegra186 and Tegra194 GPC DMA controller
+ driver. The DMA controller is having multiple DMA channel which
+ can be configured for different peripherals like UART, SPI, etc
+ which are on APB bus.
+ This DMA controller transfers data from memory to peripheral fifo
+ or vice versa. It also supports memory to memory data transfer.
+
config TIMB_DMA
tristate "Timberdale FPGA DMA support"
depends on MFD_TIMBERDALE || COMPILE_TEST
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index e60f813..43e3a6e 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -76,6 +76,7 @@ obj-$(CONFIG_S3C24XX_DMAC) += s3c24xx-dma.o
obj-$(CONFIG_TXX9_DMAC) += txx9dmac.o
obj-$(CONFIG_TEGRA20_APB_DMA) += tegra20-apb-dma.o
obj-$(CONFIG_TEGRA210_ADMA) += tegra210-adma.o
+obj-$(CONFIG_TEGRA_GPC_DMA) += tegra-gpc-dma.o
obj-$(CONFIG_TIMB_DMA) += timb_dma.o
obj-$(CONFIG_UNIPHIER_MDMAC) += uniphier-mdmac.o
obj-$(CONFIG_UNIPHIER_XDMAC) += uniphier-xdmac.o
diff --git a/drivers/dma/tegra-gpc-dma.c b/drivers/dma/tegra-gpc-dma.c
new file mode 100644
index 0000000..92b7219
--- /dev/null
+++ b/drivers/dma/tegra-gpc-dma.c
@@ -0,0 +1,1512 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * DMA driver for Nvidia's Tegra186 and Tegra194 GPC DMA controller.
+ *
+ * Copyright (c) 2014-2020, NVIDIA CORPORATION. All rights reserved.
+ */
+
+#include <linux/bitops.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/reset.h>
+#include <linux/slab.h>
+#include <linux/version.h>
+#include <dt-bindings/memory/tegra186-mc.h>
+#include "virt-dma.h"
+
+/* CSR register */
+#define TEGRA_GPCDMA_CHAN_CSR 0x00
+#define TEGRA_GPCDMA_CSR_ENB BIT(31)
+#define TEGRA_GPCDMA_CSR_IE_EOC BIT(30)
+#define TEGRA_GPCDMA_CSR_ONCE BIT(27)
+#define TEGRA_GPCDMA_CSR_FC_MODE_NO_MMIO (0 << 24)
+#define TEGRA_GPCDMA_CSR_FC_MODE_ONE_MMIO (1 << 24)
+#define TEGRA_GPCDMA_CSR_FC_MODE_TWO_MMIO (2 << 24)
+#define TEGRA_GPCDMA_CSR_FC_MODE_FOUR_MMIO (3 << 24)
+#define TEGRA_GPCDMA_CSR_DMA_IO2MEM_NO_FC (0 << 21)
+#define TEGRA_GPCDMA_CSR_DMA_IO2MEM_FC (1 << 21)
+#define TEGRA_GPCDMA_CSR_DMA_MEM2IO_NO_FC (2 << 21)
+#define TEGRA_GPCDMA_CSR_DMA_MEM2IO_FC (3 << 21)
+#define TEGRA_GPCDMA_CSR_DMA_MEM2MEM (4 << 21)
+#define TEGRA_GPCDMA_CSR_DMA_FIXED_PAT (6 << 21)
+#define TEGRA_GPCDMA_CSR_REQ_SEL_SHIFT 16
+#define TEGRA_GPCDMA_CSR_REQ_SEL_MASK 0x1F
+#define TEGRA_GPCDMA_CSR_REQ_SEL_UNUSED 0x4
+#define TEGRA_GPCDMA_CSR_IRQ_MASK BIT(15)
+#define TEGRA_GPCDMA_CSR_WEIGHT_SHIFT 10
+
+/* STATUS register */
+#define TEGRA_GPCDMA_CHAN_STATUS 0x004
+#define TEGRA_GPCDMA_STATUS_BUSY BIT(31)
+#define TEGRA_GPCDMA_STATUS_ISE_EOC BIT(30)
+#define TEGRA_GPCDMA_STATUS_PING_PONG BIT(28)
+#define TEGRA_GPCDMA_STATUS_DMA_ACTIVITY BIT(27)
+#define TEGRA_GPCDMA_STATUS_CHANNEL_PAUSE BIT(26)
+#define TEGRA_GPCDMA_STATUS_CHANNEL_RX BIT(25)
+#define TEGRA_GPCDMA_STATUS_CHANNEL_TX BIT(24)
+#define TEGRA_GPCDMA_STATUS_IRQ_INTR_STA BIT(23)
+#define TEGRA_GPCDMA_STATUS_IRQ_STA BIT(21)
+#define TEGRA_GPCDMA_STATUS_IRQ_TRIG_STA BIT(20)
+
+#define TEGRA_GPCDMA_CHAN_CSRE 0x008
+#define TEGRA_GPCDMA_CHAN_CSRE_PAUSE BIT(31)
+
+/* Source address */
+#define TEGRA_GPCDMA_CHAN_SRC_PTR 0x00C
+
+/* Destination address */
+#define TEGRA_GPCDMA_CHAN_DST_PTR 0x010
+
+/* High address pointer */
+#define TEGRA_GPCDMA_CHAN_HIGH_ADDR_PTR 0x014
+#define TEGRA_GPCDMA_HIGH_ADDR_SCR_PTR_SHIFT 0
+#define TEGRA_GPCDMA_HIGH_ADDR_SCR_PTR_MASK 0xFF
+#define TEGRA_GPCDMA_HIGH_ADDR_DST_PTR_SHIFT 16
+#define TEGRA_GPCDMA_HIGH_ADDR_DST_PTR_MASK 0xFF
+
+/* MC sequence register */
+#define TEGRA_GPCDMA_CHAN_MCSEQ 0x18
+#define TEGRA_GPCDMA_MCSEQ_DATA_SWAP BIT(31)
+#define TEGRA_GPCDMA_MCSEQ_REQ_COUNT_SHIFT 25
+#define TEGRA_GPCDMA_MCSEQ_BURST_2 (0 << 23)
+#define TEGRA_GPCDMA_MCSEQ_BURST_16 (3 << 23)
+#define TEGRA_GPCDMA_MCSEQ_WRAP1_SHIFT 20
+#define TEGRA_GPCDMA_MCSEQ_WRAP0_SHIFT 17
+#define TEGRA_GPCDMA_MCSEQ_WRAP_NONE 0
+#define TEGRA_GPCDMA_MCSEQ_MC_PROT_SHIFT 14
+#define TEGRA_GPCDMA_MCSEQ_STREAM_ID1_SHIFT 7
+#define TEGRA_GPCDMA_MCSEQ_STREAM_ID0_SHIFT 0
+#define TEGRA_GPCDMA_MCSEQ_STREAM_ID_MASK 0x7F
+
+/* MMIO sequence register */
+#define TEGRA_GPCDMA_CHAN_MMIOSEQ 0x01c
+#define TEGRA_GPCDMA_MMIOSEQ_DBL_BUF BIT(31)
+#define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_8 (0 << 28)
+#define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_16 (1 << 28)
+#define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_32 (2 << 28)
+#define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_64 (3 << 28)
+#define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_128 (4 << 28)
+#define TEGRA_GPCDMA_MMIOSEQ_DATA_SWAP BIT(27)
+#define TEGRA_GPCDMA_MMIOSEQ_BURST_1 (0 << 23)
+#define TEGRA_GPCDMA_MMIOSEQ_BURST_2 (1 << 23)
+#define TEGRA_GPCDMA_MMIOSEQ_BURST_4 (3 << 23)
+#define TEGRA_GPCDMA_MMIOSEQ_BURST_8 (7 << 23)
+#define TEGRA_GPCDMA_MMIOSEQ_BURST_16 (15 << 23)
+#define TEGRA_GPCDMA_MMIOSEQ_MASTER_ID_SHIFT 19
+#define TEGRA_GPCDMA_MMIOSEQ_WRAP_WORD_SHIFT 16
+#define TEGRA_GPCDMA_MMIOSEQ_MMIO_PROT_SHIFT 7
+
+/* Channel WCOUNT */
+#define TEGRA_GPCDMA_CHAN_WCOUNT 0x20
+
+/* Transfer count */
+#define TEGRA_GPCDMA_CHAN_XFER_COUNT 0x24
+
+/* DMA byte count status */
+#define TEGRA_GPCDMA_CHAN_DMA_BYTE_STATUS 0x28
+
+/* Error Status Register */
+#define TEGRA_GPCDMA_CHAN_ERR_STATUS 0x30
+#define TEGRA_GPCDMA_CHAN_ERR_TYPE_SHIFT (8)
+#define TEGRA_GPCDMA_CHAN_ERR_TYPE_MASK (0xF)
+#define TEGRA_GPCDMA_CHAN_ERR_TYPE(err) ( \
+ ((err) >> TEGRA_GPCDMA_CHAN_ERR_TYPE_SHIFT) & \
+ TEGRA_GPCDMA_CHAN_ERR_TYPE_MASK)
+#define TEGRA_DMA_BM_FIFO_FULL_ERR (0xF)
+#define TEGRA_DMA_PERIPH_FIFO_FULL_ERR (0xE)
+#define TEGRA_DMA_PERIPH_ID_ERR (0xD)
+#define TEGRA_DMA_STREAM_ID_ERR (0xC)
+#define TEGRA_DMA_MC_SLAVE_ERR (0xB)
+#define TEGRA_DMA_MMIO_SLAVE_ERR (0xA)
+
+/* Fixed Pattern */
+#define TEGRA_GPCDMA_CHAN_FIXED_PATTERN 0x34
+
+#define TEGRA_GPCDMA_CHAN_TZ 0x38
+#define TEGRA_GPCDMA_CHAN_TZ_MMIO_PROT_1 BIT(0)
+#define TEGRA_GPCDMA_CHAN_TZ_MC_PROT_1 BIT(1)
+
+#define TEGRA_GPCDMA_CHAN_SPARE 0x3c
+#define TEGRA_GPCDMA_CHAN_SPARE_EN_LEGACY_FC BIT(16)
+
+/*
+ * 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_GPCDMA_BURST_COMPLETE_TIME 20
+#define TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT 100
+
+/* Channel base address offset from GPCDMA base address */
+#define TEGRA_GPCDMA_CHANNEL_BASE_ADD_OFFSET 0x10000
+
+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.
+ * @max_dma_count: Maximum DMA transfer count supported by DMA controller.
+ * @hw_support_pause: DMA HW engine support pause of the channel.
+ */
+struct tegra_dma_chip_data {
+ int nr_channels;
+ int channel_reg_size;
+ int max_dma_count;
+ bool hw_support_pause;
+};
+
+/* DMA channel registers */
+struct tegra_dma_channel_regs {
+ unsigned long csr;
+ unsigned long src_ptr;
+ unsigned long dst_ptr;
+ unsigned long high_addr_ptr;
+ unsigned long mc_seq;
+ unsigned long mmio_seq;
+ unsigned long wcount;
+ unsigned long fixed_pattern;
+};
+
+/*
+ * 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 skipped;
+ 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 virt_dma_desc vd;
+ int bytes_requested;
+ int bytes_transferred;
+ struct tegra_dma_channel *tdc;
+};
+
+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 virt_dma_chan vc;
+ struct tegra_dma_desc *dma_desc;
+ struct tegra_dma_desc *pending_dma_desc;
+ char name[30];
+ bool config_init;
+ int id;
+ int irq;
+ unsigned long chan_base_offset;
+ raw_spinlock_t lock;
+ bool busy;
+ bool is_pending;
+ struct tegra_dma *tdma;
+
+ /* List for managing pending sg requests */
+ struct list_head pending_sg_req;
+
+ /* ISR handler and tasklet for bottom half of isr handling */
+ dma_isr_handler isr_handler;
+
+ /* Channel-slave specific configuration */
+ 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;
+ void __iomem *base_addr;
+ const struct tegra_dma_chip_data *chip_data;
+ struct reset_control *rst;
+ /* Last member of the structure */
+ struct tegra_dma_channel channels[0];
+};
+
+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, vc.chan);
+}
+
+static inline struct tegra_dma_desc *vd_to_tegra_dma_desc(
+ struct virt_dma_desc *vd)
+{
+ return container_of(vd, struct tegra_dma_desc, vd);
+}
+
+static inline struct device *tdc2dev(struct tegra_dma_channel *tdc)
+{
+ return tdc->vc.chan.device->dev;
+}
+
+static void tegra_dma_dump_chan_regs(struct tegra_dma_channel *tdc)
+{
+ pr_info("DMA Channel %d name %s register dump:\n",
+ tdc->id, tdc->name);
+ pr_info("CSR %x STA %x CSRE %x SRC %x DST %x\n",
+ tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSR),
+ tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS),
+ tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSRE),
+ tdc_read(tdc, TEGRA_GPCDMA_CHAN_SRC_PTR),
+ tdc_read(tdc, TEGRA_GPCDMA_CHAN_DST_PTR)
+ );
+ pr_info("MCSEQ %x IOSEQ %x WCNT %x XFER %x BSTA %x\n",
+ tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ),
+ tdc_read(tdc, TEGRA_GPCDMA_CHAN_MMIOSEQ),
+ tdc_read(tdc, TEGRA_GPCDMA_CHAN_WCOUNT),
+ tdc_read(tdc, TEGRA_GPCDMA_CHAN_XFER_COUNT),
+ tdc_read(tdc, TEGRA_GPCDMA_CHAN_DMA_BYTE_STATUS)
+ );
+ pr_info("DMA ERR_STA %x\n",
+ tdc_read(tdc, TEGRA_GPCDMA_CHAN_ERR_STATUS));
+}
+
+static void tegra_dma_desc_free(struct virt_dma_desc *vd)
+{
+ struct tegra_dma_desc *dma_desc = vd_to_tegra_dma_desc(vd);
+ unsigned long flags;
+
+ if (!dma_desc)
+ return;
+ raw_spin_lock_irqsave(&dma_desc->tdc->lock, flags);
+ kfree(dma_desc);
+ raw_spin_unlock_irqrestore(&dma_desc->tdc->lock, flags);
+ dma_desc->tdc = NULL;
+}
+
+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 == -1)
+ tdc->slave_id = sconfig->slave_id;
+ tdc->config_init = true;
+ return 0;
+}
+
+static int tegra_dma_pause(struct tegra_dma_channel *tdc)
+{
+ int timeout = TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT;
+
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSRE, TEGRA_GPCDMA_CHAN_CSRE_PAUSE);
+
+ /* Wait until busy bit is de-asserted */
+ do {
+ if (!(tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS) &
+ TEGRA_GPCDMA_STATUS_BUSY))
+ break;
+ udelay(TEGRA_GPCDMA_BURST_COMPLETE_TIME);
+ timeout -= TEGRA_GPCDMA_BURST_COMPLETE_TIME;
+ } while (timeout);
+
+ if (!timeout) {
+ dev_err(tdc2dev(tdc), "DMA pause timed out\n");
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+static void tegra_dma_stop(struct tegra_dma_channel *tdc)
+{
+ u32 csr;
+ u32 status;
+
+ /* Disable interrupts */
+ csr = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSR);
+ csr &= ~TEGRA_GPCDMA_CSR_IE_EOC;
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR, csr);
+
+ /* Disable DMA */
+ csr &= ~TEGRA_GPCDMA_CSR_ENB;
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR, csr);
+
+ /* Clear interrupt status if it is there */
+ status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS);
+ if (status & TEGRA_GPCDMA_STATUS_ISE_EOC) {
+ dev_dbg(tdc2dev(tdc), "%s():clearing interrupt\n", __func__);
+ tdc_write(tdc, TEGRA_GPCDMA_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_GPCDMA_CHAN_WCOUNT, ch_regs->wcount);
+
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR, 0);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_SRC_PTR, ch_regs->src_ptr);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_DST_PTR, ch_regs->dst_ptr);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_HIGH_ADDR_PTR, ch_regs->high_addr_ptr);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_FIXED_PATTERN, ch_regs->fixed_pattern);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_MMIOSEQ, ch_regs->mmio_seq);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_MCSEQ, ch_regs->mc_seq);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSRE, 0);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR, ch_regs->csr);
+
+ /* Start DMA */
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR,
+ ch_regs->csr | TEGRA_GPCDMA_CSR_ENB);
+}
+
+static void tdc_start_head_req(struct tegra_dma_channel *tdc)
+{
+ struct tegra_dma_sg_req *sg_req;
+ struct virt_dma_desc *vdesc;
+
+ if (list_empty(&tdc->pending_sg_req))
+ return;
+
+ if (tdc->is_pending)
+ return;
+
+ vdesc = vchan_next_desc(&tdc->vc);
+ if (!vdesc)
+ return;
+ list_del(&vdesc->node);
+ tdc->dma_desc = vd_to_tegra_dma_desc(vdesc);
+ tdc->is_pending = true;
+ tdc->dma_desc->tdc = tdc;
+ 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->skipped = false;
+ tdc->busy = true;
+}
+
+static void tegra_dma_abort_all(struct tegra_dma_channel *tdc)
+{
+ 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_del(&sgreq->node);
+ kfree(sgreq);
+ }
+ tdc->isr_handler = NULL;
+}
+
+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;
+
+ if (sgreq->last_sg) {
+ vchan_cookie_complete(&tdc->dma_desc->vd);
+ tdc->is_pending = false;
+ tdc->dma_desc = NULL;
+ }
+ list_del(&sgreq->node);
+ kfree(sgreq);
+
+ if (to_terminate || list_empty(&tdc->pending_sg_req))
+ return;
+
+ tdc_start_head_req(tdc);
+}
+
+static void tegra_dma_chan_decode_error(struct tegra_dma_channel *tdc,
+ unsigned int err_status)
+{
+ switch (TEGRA_GPCDMA_CHAN_ERR_TYPE(err_status)) {
+ case TEGRA_DMA_BM_FIFO_FULL_ERR:
+ dev_err(tdc->tdma->dev,
+ "GPCDMA CH%d bm fifo full\n", tdc->id);
+ break;
+
+ case TEGRA_DMA_PERIPH_FIFO_FULL_ERR:
+ dev_err(tdc->tdma->dev,
+ "GPCDMA CH%d peripheral fifo full\n", tdc->id);
+ break;
+
+ case TEGRA_DMA_PERIPH_ID_ERR:
+ dev_err(tdc->tdma->dev,
+ "GPCDMA CH%d illegal peripheral id\n", tdc->id);
+ break;
+
+ case TEGRA_DMA_STREAM_ID_ERR:
+ dev_err(tdc->tdma->dev,
+ "GPCDMA CH%d illegal stream id\n", tdc->id);
+ break;
+
+ case TEGRA_DMA_MC_SLAVE_ERR:
+ dev_err(tdc->tdma->dev,
+ "GPCDMA CH%d mc slave error\n", tdc->id);
+ break;
+
+ case TEGRA_DMA_MMIO_SLAVE_ERR:
+ dev_err(tdc->tdma->dev,
+ "GPCDMA CH%d mmio slave error\n", tdc->id);
+ break;
+
+ default:
+ dev_err(tdc->tdma->dev,
+ "GPCDMA CH%d security violation %x\n", tdc->id,
+ err_status);
+ }
+}
+
+static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
+{
+ struct tegra_dma_channel *tdc = dev_id;
+ unsigned long status;
+ unsigned long flags;
+ unsigned int err_status;
+
+ raw_spin_lock_irqsave(&tdc->lock, flags);
+
+ status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS);
+ err_status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_ERR_STATUS);
+
+ if (err_status) {
+ tegra_dma_chan_decode_error(tdc, err_status);
+ tegra_dma_dump_chan_regs(tdc);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_ERR_STATUS, 0xFFFFFFFF);
+ }
+
+ if (status & TEGRA_GPCDMA_STATUS_ISE_EOC) {
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_STATUS,
+ TEGRA_GPCDMA_STATUS_ISE_EOC);
+ if (tdc->isr_handler)
+ tdc->isr_handler(tdc, false);
+ else {
+ dev_err(tdc->tdma->dev,
+ "GPCDMA CH%d: status %lx ISR handler absent!\n",
+ tdc->id, status);
+ tegra_dma_dump_chan_regs(tdc);
+ }
+ raw_spin_unlock_irqrestore(&tdc->lock, flags);
+ return IRQ_HANDLED;
+ }
+
+ raw_spin_unlock_irqrestore(&tdc->lock, flags);
+ return IRQ_NONE;
+}
+
+static void tegra_dma_issue_pending(struct dma_chan *dc)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ unsigned long flags;
+
+ raw_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)
+ if (vchan_issue_pending(&tdc->vc))
+ tdc_start_head_req(tdc);
+
+end:
+ raw_spin_unlock_irqrestore(&tdc->lock, flags);
+}
+
+static void tegra_dma_reset_client(struct tegra_dma_channel *tdc)
+{
+ uint32_t csr = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSR);
+
+ csr &= ~(TEGRA_GPCDMA_CSR_REQ_SEL_MASK <<
+ TEGRA_GPCDMA_CSR_REQ_SEL_SHIFT);
+ csr |= (TEGRA_GPCDMA_CSR_REQ_SEL_UNUSED
+ << TEGRA_GPCDMA_CSR_REQ_SEL_SHIFT);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR, csr);
+}
+
+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;
+ unsigned long flags;
+ unsigned long status, burst_time;
+ unsigned long wcount = 0;
+ bool was_busy;
+ int err;
+
+ raw_spin_lock_irqsave(&tdc->lock, flags);
+ if (list_empty(&tdc->pending_sg_req)) {
+ raw_spin_unlock_irqrestore(&tdc->lock, flags);
+ return 0;
+ }
+
+ if (!tdc->busy)
+ goto skip_dma_stop;
+
+ if (tdc->tdma->chip_data->hw_support_pause) {
+ err = tegra_dma_pause(tdc);
+ if (err) {
+ raw_spin_unlock_irqrestore(&tdc->lock, flags);
+ return err;
+ }
+ } else {
+ /* Before Reading DMA status to figure out number
+ * of bytes transferred by DMA channel:
+ * Change the client associated with the DMA channel
+ * to stop DMA engine from starting any more bursts for
+ * the given client and wait for in flight bursts to complete
+ */
+ tegra_dma_reset_client(tdc);
+
+ /* Wait for in flight data transfer to finish */
+ udelay(TEGRA_GPCDMA_BURST_COMPLETE_TIME);
+
+ /* If TX/RX path is still active wait till it becomes
+ * inactive
+ */
+ burst_time = 0;
+ while (burst_time < TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT) {
+ status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS);
+ if (status & (TEGRA_GPCDMA_STATUS_CHANNEL_TX |
+ TEGRA_GPCDMA_STATUS_CHANNEL_RX)) {
+ udelay(5);
+ burst_time += 5;
+ } else
+ break;
+ }
+
+ if (burst_time >= TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT) {
+ pr_err("Timeout waiting for DMA burst completion!\n");
+ tegra_dma_dump_chan_regs(tdc);
+ }
+ }
+
+ status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS);
+ wcount = tdc_read(tdc, TEGRA_GPCDMA_CHAN_XFER_COUNT);
+ if (status & TEGRA_GPCDMA_STATUS_ISE_EOC) {
+ dev_dbg(tdc2dev(tdc), "%s():handling isr\n", __func__);
+ tdc->isr_handler(tdc, true);
+ status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS);
+ wcount = tdc_read(tdc, TEGRA_GPCDMA_CHAN_XFER_COUNT);
+ }
+
+ 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 +=
+ sgreq->req_len - (wcount * 4);
+ }
+
+skip_dma_stop:
+ tegra_dma_abort_all(tdc);
+ vchan_free_chan_resources(&tdc->vc);
+ if (tdc->is_pending) {
+ tdc->pending_dma_desc = tdc->dma_desc;
+ tdc->is_pending = false;
+ tdc->dma_desc = NULL;
+ }
+
+ raw_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;
+
+ raw_spin_lock_irqsave(&tdc->lock, flags);
+
+ ret = dma_cookie_status(dc, cookie, txstate);
+ if (ret == DMA_COMPLETE) {
+ raw_spin_unlock_irqrestore(&tdc->lock, flags);
+ return ret;
+ }
+
+ /* Check on pending dma desc*/
+ if(tdc->pending_dma_desc) {
+ dma_desc = tdc->pending_dma_desc;
+ tdc->pending_dma_desc = NULL;
+ if (dma_desc->vd.tx.cookie == cookie) {
+ residual = dma_desc->bytes_requested -
+ (dma_desc->bytes_transferred %
+ dma_desc->bytes_requested);
+ dma_set_residue(txstate, residual);
+ kfree(dma_desc);
+ raw_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->vd.tx.cookie == cookie) {
+ residual = dma_desc->bytes_requested -
+ (dma_desc->bytes_transferred %
+ dma_desc->bytes_requested);
+ dma_set_residue(txstate, residual);
+ raw_spin_unlock_irqrestore(&tdc->lock, flags);
+ return ret;
+ }
+ }
+
+ dev_dbg(tdc2dev(tdc), "cookie %d does not found\n", cookie);
+ raw_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_GPCDMA_MMIOSEQ_BUS_WIDTH_8;
+ case DMA_SLAVE_BUSWIDTH_2_BYTES:
+ return TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_16;
+ case DMA_SLAVE_BUSWIDTH_4_BYTES:
+ return TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_32;
+ case DMA_SLAVE_BUSWIDTH_8_BYTES:
+ return TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_64;
+ default:
+ dev_warn(tdc2dev(tdc),
+ "slave bw is not supported, using 32bits\n");
+ return TEGRA_GPCDMA_MMIOSEQ_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_mmio_width;
+
+ /*
+ * burst_size from client is in terms of the bus_width.
+ * convert that into words.
+ */
+ burst_byte = burst_size * slave_bw;
+ burst_mmio_width = burst_byte / 4;
+
+ /* If burst size is 0 then calculate the burst size based on length */
+ if (!burst_mmio_width) {
+ if (len & 0xF)
+ return TEGRA_GPCDMA_MMIOSEQ_BURST_1;
+ else if ((len >> 3) & 0x1)
+ return TEGRA_GPCDMA_MMIOSEQ_BURST_2;
+ else if ((len >> 4) & 0x1)
+ return TEGRA_GPCDMA_MMIOSEQ_BURST_4;
+ else if ((len >> 5) & 0x1)
+ return TEGRA_GPCDMA_MMIOSEQ_BURST_8;
+ else
+ return TEGRA_GPCDMA_MMIOSEQ_BURST_16;
+ }
+ if (burst_mmio_width < 2)
+ return TEGRA_GPCDMA_MMIOSEQ_BURST_1;
+ else if (burst_mmio_width < 4)
+ return TEGRA_GPCDMA_MMIOSEQ_BURST_2;
+ else if (burst_mmio_width < 8)
+ return TEGRA_GPCDMA_MMIOSEQ_BURST_4;
+ else if (burst_mmio_width < 16)
+ return TEGRA_GPCDMA_MMIOSEQ_BURST_8;
+ else
+ return TEGRA_GPCDMA_MMIOSEQ_BURST_16;
+}
+
+static int get_transfer_param(struct tegra_dma_channel *tdc,
+ enum dma_transfer_direction direction, unsigned long *apb_addr,
+ unsigned long *mmio_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;
+ *mmio_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_GPCDMA_CSR_DMA_MEM2IO_FC;
+ return 0;
+
+ case DMA_DEV_TO_MEM:
+ *apb_addr = tdc->dma_sconfig.src_addr;
+ *mmio_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 = TEGRA_GPCDMA_CSR_DMA_IO2MEM_FC;
+ return 0;
+ case DMA_MEM_TO_MEM:
+ *burst_size = tdc->dma_sconfig.src_addr_width;
+ *csr = TEGRA_GPCDMA_CSR_DMA_MEM2MEM;
+ return 0;
+ default:
+ dev_err(tdc2dev(tdc), "Dma direction is not supported\n");
+ return -EINVAL;
+ }
+ return -EINVAL;
+}
+
+static struct dma_async_tx_descriptor *tegra_dma_prep_dma_memset(
+ struct dma_chan *dc, dma_addr_t dest, int value, size_t len,
+ unsigned long flags)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ struct tegra_dma_desc *dma_desc;
+ struct list_head req_list;
+ struct tegra_dma_sg_req *sg_req = NULL;
+ unsigned long csr, mc_seq;
+
+ INIT_LIST_HEAD(&req_list);
+ /* Set dma mode to fixed pattern */
+ csr = TEGRA_GPCDMA_CSR_DMA_FIXED_PAT;
+ /* Enable once or continuous mode */
+ csr |= TEGRA_GPCDMA_CSR_ONCE;
+ /* Enable IRQ mask */
+ csr |= TEGRA_GPCDMA_CSR_IRQ_MASK;
+ /* Enable the dma interrupt */
+ if (flags & DMA_PREP_INTERRUPT)
+ csr |= TEGRA_GPCDMA_CSR_IE_EOC;
+ /* Configure default priority weight for the channel */
+ csr |= (1 << TEGRA_GPCDMA_CSR_WEIGHT_SHIFT);
+
+ mc_seq = tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
+ /* retain stream-id and clean rest */
+ mc_seq &= (TEGRA_GPCDMA_MCSEQ_STREAM_ID_MASK <<
+ TEGRA_GPCDMA_MCSEQ_STREAM_ID0_SHIFT);
+
+ /* Set the address wrapping */
+ mc_seq |= TEGRA_GPCDMA_MCSEQ_WRAP_NONE <<
+ TEGRA_GPCDMA_MCSEQ_WRAP0_SHIFT;
+ mc_seq |= TEGRA_GPCDMA_MCSEQ_WRAP_NONE <<
+ TEGRA_GPCDMA_MCSEQ_WRAP1_SHIFT;
+
+ /* Program outstanding MC requests */
+ mc_seq |= (1 << TEGRA_GPCDMA_MCSEQ_REQ_COUNT_SHIFT);
+ /* Set burst size */
+ mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_16;
+
+ dma_desc = kzalloc(sizeof(struct tegra_dma_desc), GFP_NOWAIT);
+ if (!dma_desc) {
+ dev_err(tdc2dev(tdc), "Dma descriptors not available\n");
+ return NULL;
+ }
+ dma_desc->bytes_requested = 0;
+ dma_desc->bytes_transferred = 0;
+
+ if ((len & 3) || (dest & 3) ||
+ (len > tdc->tdma->chip_data->max_dma_count)) {
+ dev_err(tdc2dev(tdc),
+ "Dma length/memory address is not supported\n");
+ kfree(dma_desc);
+ return NULL;
+ }
+
+ sg_req = kzalloc(sizeof(struct tegra_dma_sg_req), GFP_NOWAIT);
+ if (!sg_req) {
+ dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
+ kfree(dma_desc);
+ return NULL;
+ }
+
+ dma_desc->bytes_requested += len;
+ sg_req->ch_regs.src_ptr = 0;
+ sg_req->ch_regs.dst_ptr = dest;
+ sg_req->ch_regs.high_addr_ptr = ((dest >> 32) &
+ TEGRA_GPCDMA_HIGH_ADDR_DST_PTR_MASK) <<
+ TEGRA_GPCDMA_HIGH_ADDR_DST_PTR_SHIFT;
+ sg_req->ch_regs.fixed_pattern = value;
+ /* Word count reg takes value as (N +1) words */
+ sg_req->ch_regs.wcount = ((len - 4) >> 2);
+ sg_req->ch_regs.csr = csr;
+ sg_req->ch_regs.mmio_seq = 0;
+ sg_req->ch_regs.mc_seq = mc_seq;
+ sg_req->configured = false;
+ sg_req->skipped = false;
+ sg_req->last_sg = false;
+ sg_req->dma_desc = dma_desc;
+ sg_req->req_len = len;
+ sg_req->last_sg = true;
+
+ list_add_tail(&sg_req->node, &tdc->pending_sg_req);
+
+ if (!tdc->isr_handler)
+ tdc->isr_handler = handle_once_dma_done;
+
+ tdc->pending_dma_desc = NULL;
+
+ return vchan_tx_prep(&tdc->vc, &dma_desc->vd, flags);
+}
+
+static struct dma_async_tx_descriptor *tegra_dma_prep_dma_memcpy(
+ struct dma_chan *dc, dma_addr_t dest, dma_addr_t src, size_t len,
+ unsigned long flags)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ struct tegra_dma_desc *dma_desc;
+ struct list_head req_list;
+ struct tegra_dma_sg_req *sg_req = NULL;
+ unsigned long csr, mc_seq;
+
+ INIT_LIST_HEAD(&req_list);
+ /* Set dma mode to memory to memory transfer */
+ csr = TEGRA_GPCDMA_CSR_DMA_MEM2MEM;
+ /* Enable once or continuous mode */
+ csr |= TEGRA_GPCDMA_CSR_ONCE;
+ /* Enable IRQ mask */
+ csr |= TEGRA_GPCDMA_CSR_IRQ_MASK;
+ /* Enable the dma interrupt */
+ if (flags & DMA_PREP_INTERRUPT)
+ csr |= TEGRA_GPCDMA_CSR_IE_EOC;
+ /* Configure default priority weight for the channel */
+ csr |= (1 << TEGRA_GPCDMA_CSR_WEIGHT_SHIFT);
+
+ mc_seq = tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
+ /* retain stream-id and clean rest */
+ mc_seq &= ((TEGRA_GPCDMA_MCSEQ_STREAM_ID_MASK <<
+ TEGRA_GPCDMA_MCSEQ_STREAM_ID0_SHIFT) |
+ (TEGRA_GPCDMA_MCSEQ_STREAM_ID_MASK <<
+ TEGRA_GPCDMA_MCSEQ_STREAM_ID1_SHIFT));
+
+ /* Set the address wrapping */
+ mc_seq |= TEGRA_GPCDMA_MCSEQ_WRAP_NONE <<
+ TEGRA_GPCDMA_MCSEQ_WRAP0_SHIFT;
+ mc_seq |= TEGRA_GPCDMA_MCSEQ_WRAP_NONE <<
+ TEGRA_GPCDMA_MCSEQ_WRAP1_SHIFT;
+
+ /* Program outstanding MC requests */
+ mc_seq |= (1 << TEGRA_GPCDMA_MCSEQ_REQ_COUNT_SHIFT);
+ /* Set burst size */
+ mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_16;
+
+ dma_desc = kzalloc(sizeof(struct tegra_dma_desc), GFP_NOWAIT);
+ if (!dma_desc) {
+ dev_err(tdc2dev(tdc), "Dma descriptors not available\n");
+ return NULL;
+ }
+
+ dma_desc->bytes_requested = 0;
+ dma_desc->bytes_transferred = 0;
+
+ if ((len & 3) || (src & 3) || (dest & 3) ||
+ (len > tdc->tdma->chip_data->max_dma_count)) {
+ dev_err(tdc2dev(tdc),
+ "Dma length/memory address is not supported\n");
+ kfree(dma_desc);
+ return NULL;
+ }
+
+ sg_req = kzalloc(sizeof(struct tegra_dma_sg_req), GFP_NOWAIT);
+ if (!sg_req) {
+ dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
+ kfree(dma_desc);
+ return NULL;
+ }
+
+ dma_desc->bytes_requested += len;
+ sg_req->ch_regs.src_ptr = src;
+ sg_req->ch_regs.dst_ptr = dest;
+ sg_req->ch_regs.high_addr_ptr = (src >> 32) &
+ TEGRA_GPCDMA_HIGH_ADDR_SCR_PTR_MASK;
+ sg_req->ch_regs.high_addr_ptr |= ((dest >> 32) &
+ TEGRA_GPCDMA_HIGH_ADDR_DST_PTR_MASK) <<
+ TEGRA_GPCDMA_HIGH_ADDR_DST_PTR_SHIFT;
+ /* Word count reg takes value as (N +1) words */
+ sg_req->ch_regs.wcount = ((len - 4) >> 2);
+ sg_req->ch_regs.csr = csr;
+ sg_req->ch_regs.mmio_seq = 0;
+ sg_req->ch_regs.mc_seq = mc_seq;
+ sg_req->configured = false;
+ sg_req->skipped = false;
+ sg_req->last_sg = false;
+ sg_req->dma_desc = dma_desc;
+ sg_req->req_len = len;
+ sg_req->last_sg = true;
+
+ list_add_tail(&sg_req->node, &tdc->pending_sg_req);
+
+ if (!tdc->isr_handler)
+ tdc->isr_handler = handle_once_dma_done;
+
+ tdc->pending_dma_desc = NULL;
+
+ return vchan_tx_prep(&tdc->vc, &dma_desc->vd, flags);
+}
+
+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, mc_seq, apb_ptr = 0, mmio_seq = 0;
+ struct list_head req_list;
+ struct tegra_dma_sg_req *sg_req = NULL;
+ u32 burst_size;
+ enum dma_slave_buswidth slave_bw = 0;
+ 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, &mmio_seq, &csr,
+ &burst_size, &slave_bw);
+ if (ret < 0)
+ return NULL;
+
+ INIT_LIST_HEAD(&req_list);
+
+ /* Enable once or continuous mode */
+ csr |= TEGRA_GPCDMA_CSR_ONCE;
+ /* Program the slave id in requestor select */
+ csr |= tdc->slave_id << TEGRA_GPCDMA_CSR_REQ_SEL_SHIFT;
+ /* Enable IRQ mask */
+ csr |= TEGRA_GPCDMA_CSR_IRQ_MASK;
+ /* Configure default priority weight for the channel*/
+ csr |= (1 << TEGRA_GPCDMA_CSR_WEIGHT_SHIFT);
+
+ /* Enable the dma interrupt */
+ if (flags & DMA_PREP_INTERRUPT)
+ csr |= TEGRA_GPCDMA_CSR_IE_EOC;
+
+ mc_seq = tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
+ /* retain stream-id and clean rest */
+ mc_seq &= (TEGRA_GPCDMA_MCSEQ_STREAM_ID_MASK <<
+ TEGRA_GPCDMA_MCSEQ_STREAM_ID0_SHIFT);
+
+ /* Set the address wrapping on both MC and MMIO side */
+ mc_seq |= TEGRA_GPCDMA_MCSEQ_WRAP_NONE <<
+ TEGRA_GPCDMA_MCSEQ_WRAP0_SHIFT;
+ mc_seq |= TEGRA_GPCDMA_MCSEQ_WRAP_NONE <<
+ TEGRA_GPCDMA_MCSEQ_WRAP1_SHIFT;
+ mmio_seq |= (1 << TEGRA_GPCDMA_MMIOSEQ_WRAP_WORD_SHIFT);
+
+ /* Program 2 MC outstanding requests by default. */
+ mc_seq |= (1 << TEGRA_GPCDMA_MCSEQ_REQ_COUNT_SHIFT);
+
+ /* Setting MC burst size depending on MMIO burst size */
+ if (burst_size == 64)
+ mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_16;
+ else
+ mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_2;
+
+ dma_desc = kzalloc(sizeof(struct tegra_dma_desc), GFP_NOWAIT);
+ if (!dma_desc) {
+ dev_err(tdc2dev(tdc), "Dma descriptors not available\n");
+ return NULL;
+ }
+
+ dma_desc->bytes_requested = 0;
+ dma_desc->bytes_transferred = 0;
+
+ /* Make transfer requests */
+ for_each_sg(sgl, sg, sg_len, i) {
+ u32 len;
+ dma_addr_t 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");
+ kfree(dma_desc);
+ return NULL;
+ }
+
+ sg_req = kzalloc(sizeof(struct tegra_dma_sg_req), GFP_NOWAIT);
+ if (!sg_req) {
+ dev_err(tdc2dev(tdc), "Dma sg-req not available\n");
+ kfree(dma_desc);
+ goto sg_alloc_error;
+ }
+
+ mmio_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
+ dma_desc->bytes_requested += len;
+
+ if (direction == DMA_MEM_TO_DEV) {
+ sg_req->ch_regs.src_ptr = mem;
+ sg_req->ch_regs.dst_ptr = apb_ptr;
+ sg_req->ch_regs.high_addr_ptr = (mem >> 32) &
+ TEGRA_GPCDMA_HIGH_ADDR_SCR_PTR_MASK;
+ } else if (direction == DMA_DEV_TO_MEM) {
+ sg_req->ch_regs.src_ptr = apb_ptr;
+ sg_req->ch_regs.dst_ptr = mem;
+ sg_req->ch_regs.high_addr_ptr = ((mem >> 32) &
+ TEGRA_GPCDMA_HIGH_ADDR_DST_PTR_MASK) <<
+ TEGRA_GPCDMA_HIGH_ADDR_DST_PTR_SHIFT;
+ }
+
+ /*
+ * Word count register takes input in words. Writing a value
+ * of N into word count register means a req of (N+1) words.
+ */
+ sg_req->ch_regs.wcount = ((len - 4) >> 2);
+ sg_req->ch_regs.csr = csr;
+ sg_req->ch_regs.mmio_seq = mmio_seq;
+ sg_req->ch_regs.mc_seq = mc_seq;
+ sg_req->configured = false;
+ sg_req->skipped = false;
+ sg_req->last_sg = false;
+ sg_req->dma_desc = dma_desc;
+ sg_req->req_len = len;
+ list_add_tail(&sg_req->node, &tdc->pending_sg_req);
+ }
+ sg_req->last_sg = true;
+
+ /*
+ * Make sure that mode should not be conflicting with currently
+ * configured mode.
+ */
+ if (!tdc->isr_handler)
+ tdc->isr_handler = handle_once_dma_done;
+
+ tdc->pending_dma_desc = NULL;
+
+ return vchan_tx_prep(&tdc->vc, &dma_desc->vd, flags);
+
+sg_alloc_error:
+ while (!list_empty(&tdc->pending_sg_req)) {
+ sg_req = list_first_entry(&tdc->pending_sg_req,
+ typeof(*sg_req), node);
+ list_del(&sg_req->node);
+ kfree(sg_req);
+ }
+ return NULL;
+}
+
+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->vc.chan);
+ tdc->config_init = false;
+ return 0;
+}
+
+static void tegra_dma_free_chan_resources(struct dma_chan *dc)
+{
+ struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
+ struct list_head sg_req_list;
+ unsigned long flags;
+
+ INIT_LIST_HEAD(&sg_req_list);
+
+ dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id);
+
+ if (tdc->busy)
+ tegra_dma_terminate_all(dc);
+
+ tasklet_kill(&tdc->vc.task);
+ raw_spin_lock_irqsave(&tdc->lock, flags);
+ tdc->pending_dma_desc = NULL;
+ list_splice_init(&tdc->pending_sg_req, &sg_req_list);
+ tdc->config_init = false;
+ tdc->isr_handler = NULL;
+ tdc->slave_id = -1;
+ raw_spin_unlock_irqrestore(&tdc->lock, flags);
+}
+
+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;
+}
+
+static const struct tegra_dma_chip_data tegra186_dma_chip_data = {
+ .nr_channels = 32,
+ .channel_reg_size = 0x10000,
+ .max_dma_count = 1024UL * 1024UL * 1024UL,
+ .hw_support_pause = false,
+};
+
+static const struct tegra_dma_chip_data tegra194_dma_chip_data = {
+ .nr_channels = 32,
+ .channel_reg_size = 0x10000,
+ .max_dma_count = 1024UL * 1024UL * 1024UL,
+ .hw_support_pause = true,
+};
+
+static const struct of_device_id tegra_dma_of_match[] = {
+ {
+ .compatible = "nvidia,tegra186-gpcdma",
+ .data = &tegra186_dma_chip_data,
+ }, {
+ .compatible = "nvidia,tegra194-gpcdma",
+ .data = &tegra194_dma_chip_data,
+ }, {
+ },
+};
+MODULE_DEVICE_TABLE(of, tegra_dma_of_match);
+
+static int tegra_dma_program_sid(struct tegra_dma_channel *tdc,
+ int chan, int stream_id)
+{
+ unsigned int reg_val = tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
+
+ reg_val &= ~(TEGRA_GPCDMA_MCSEQ_STREAM_ID_MASK <<
+ TEGRA_GPCDMA_MCSEQ_STREAM_ID0_SHIFT);
+ reg_val &= ~(TEGRA_GPCDMA_MCSEQ_STREAM_ID_MASK <<
+ TEGRA_GPCDMA_MCSEQ_STREAM_ID1_SHIFT);
+
+ reg_val |= (stream_id << TEGRA_GPCDMA_MCSEQ_STREAM_ID0_SHIFT);
+ reg_val |= (stream_id << TEGRA_GPCDMA_MCSEQ_STREAM_ID1_SHIFT);
+
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_MCSEQ, reg_val);
+ return 0;
+}
+
+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;
+ struct tegra_dma_chip_data *chip_data = NULL;
+ int start_chan_idx = 0;
+ int nr_chans, stream_id;
+
+ if (pdev->dev.of_node) {
+ const struct of_device_id *match;
+
+ match = of_match_device(of_match_ptr(tegra_dma_of_match),
+ &pdev->dev);
+ if (!match) {
+ dev_err(&pdev->dev, "Error: No device match found\n");
+ return -ENODEV;
+ }
+ cdata = match->data;
+
+ ret = of_property_read_u32(pdev->dev.of_node, "dma-channels",
+ &nr_chans);
+ if (!ret) {
+ /* Allocate chip data and update number of channels */
+ chip_data =
+ devm_kzalloc(&pdev->dev,
+ sizeof(struct tegra_dma_chip_data),
+ GFP_KERNEL);
+ if (!chip_data) {
+ dev_err(&pdev->dev, "Error: memory allocation failed\n");
+ return -ENOMEM;
+ }
+ memcpy(chip_data, cdata,
+ sizeof(struct tegra_dma_chip_data));
+ chip_data->nr_channels = nr_chans;
+ cdata = chip_data;
+ }
+ ret = of_property_read_u32(pdev->dev.of_node,
+ "nvidia,start-dma-channel-index",
+ &start_chan_idx);
+ if (ret)
+ start_chan_idx = 0;
+
+ ret = of_property_read_u32(pdev->dev.of_node,
+ "nvidia,stream-id", &stream_id);
+ if (ret)
+ stream_id = TEGRA186_SID_GPCDMA_0;
+
+ } else {
+ /* If no device tree then fallback to chip data */
+ cdata =
+ (struct tegra_dma_chip_data *)pdev->id_entry->driver_data;
+ stream_id = TEGRA186_SID_GPCDMA_0;
+ }
+
+ tdma = devm_kzalloc(&pdev->dev, sizeof(*tdma) + cdata->nr_channels *
+ sizeof(struct tegra_dma_channel), GFP_KERNEL);
+ if (!tdma)
+ return -ENOMEM;
+
+ tdma->dev = &pdev->dev;
+ tdma->chip_data = cdata;
+ platform_set_drvdata(pdev, tdma);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "No mem resource for DMA\n");
+ return -EINVAL;
+ }
+
+ tdma->base_addr = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(tdma->base_addr))
+ return PTR_ERR(tdma->base_addr);
+
+ tdma->rst = devm_reset_control_get(&pdev->dev, "gpcdma");
+ if (IS_ERR(tdma->rst)) {
+ dev_err(&pdev->dev, "Missing controller reset\n");
+ return PTR_ERR(tdma->rst);
+ }
+ reset_control_reset(tdma->rst);
+
+ /* no support for pd domain hence removing call to add pd
+ * device tegra_pd_add_device(&pdev->dev);
+ */
+
+ tdma->dma_dev.dev = &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];
+
+ tdc->chan_base_offset = TEGRA_GPCDMA_CHANNEL_BASE_ADD_OFFSET +
+ start_chan_idx * cdata->channel_reg_size +
+ i * cdata->channel_reg_size;
+ res = platform_get_resource(pdev, IORESOURCE_IRQ,
+ start_chan_idx + 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), "gpcdma.%d", i);
+
+ tdc->tdma = tdma;
+ tdc->id = i;
+ tdc->slave_id = -1;
+
+ vchan_init(&tdc->vc, &tdma->dma_dev);
+ tdc->vc.desc_free = tegra_dma_desc_free;
+ raw_spin_lock_init(&tdc->lock);
+
+ INIT_LIST_HEAD(&tdc->pending_sg_req);
+ tdc->pending_dma_desc = NULL;
+
+ /* program stream-id for this channel */
+ tegra_dma_program_sid(tdc, i, stream_id);
+ }
+
+ dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask);
+ dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask);
+ dma_cap_set(DMA_MEMCPY, tdma->dma_dev.cap_mask);
+ dma_cap_set(DMA_MEMSET, tdma->dma_dev.cap_mask);
+
+ /*
+ * Only word aligned transfers are supported. Set the copy
+ * alignment shift.
+ */
+ tdma->dma_dev.copy_align = 2;
+ tdma->dma_dev.fill_align = 2;
+ 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_memcpy = tegra_dma_prep_dma_memcpy;
+ tdma->dma_dev.device_prep_dma_memset = tegra_dma_prep_dma_memset;
+ 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;
+
+ /* Register DMA channel interrupt handlers after everything is setup */
+ for (i = 0; i < cdata->nr_channels; i++) {
+ struct tegra_dma_channel *tdc = &tdma->channels[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",
+ i, ret);
+ goto err_irq;
+ }
+ }
+
+ ret = dma_async_device_register(&tdma->dma_dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "GPC 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,
+ "GPC DMA OF registration failed %d\n", ret);
+ goto err_unregister_dma_dev;
+ }
+
+ dev_info(&pdev->dev, "GPC DMA driver register %d channels\n",
+ cdata->nr_channels);
+ return 0;
+
+err_unregister_dma_dev:
+ dma_async_device_unregister(&tdma->dma_dev);
+err_irq:
+ /* no support for pd domain hence removing call to remove pd
+ * device tegra_pd_remove_device(&pdev->dev);
+ */
+ return ret;
+}
+
+static int tegra_dma_remove(struct platform_device *pdev)
+{
+ struct tegra_dma *tdma = platform_get_drvdata(pdev);
+
+ dma_async_device_unregister(&tdma->dma_dev);
+
+ /* no support for pd domain hence removing call to remove pd
+ * device tegra_pd_remove_device(&pdev->dev);
+ */
+ 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;
+
+ 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_GPCDMA_CHAN_CSR);
+ ch_reg->src_ptr = tdc_read(tdc, TEGRA_GPCDMA_CHAN_SRC_PTR);
+ ch_reg->dst_ptr = tdc_read(tdc, TEGRA_GPCDMA_CHAN_DST_PTR);
+ ch_reg->high_addr_ptr = tdc_read(tdc,
+ TEGRA_GPCDMA_CHAN_HIGH_ADDR_PTR);
+ ch_reg->mc_seq = tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
+ ch_reg->mmio_seq = tdc_read(tdc, TEGRA_GPCDMA_CHAN_MMIOSEQ);
+ ch_reg->wcount = tdc_read(tdc, TEGRA_GPCDMA_CHAN_WCOUNT);
+ }
+ return 0;
+}
+
+static int tegra_dma_pm_resume(struct device *dev)
+{
+ struct tegra_dma *tdma = dev_get_drvdata(dev);
+ int i;
+
+ 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_GPCDMA_CHAN_WCOUNT, ch_reg->wcount);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_DST_PTR, ch_reg->dst_ptr);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_SRC_PTR, ch_reg->src_ptr);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_HIGH_ADDR_PTR,
+ ch_reg->high_addr_ptr);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_MMIOSEQ, ch_reg->mmio_seq);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_MCSEQ, ch_reg->mc_seq);
+ tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR,
+ (ch_reg->csr & ~TEGRA_GPCDMA_CSR_ENB));
+ }
+ return 0;
+}
+
+#endif
+
+static const struct dev_pm_ops tegra_dma_dev_pm_ops = {
+#ifdef CONFIG_PM_SLEEP
+ SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(tegra_dma_pm_suspend, tegra_dma_pm_resume)
+#endif
+};
+
+static struct platform_driver tegra_dmac_driver = {
+ .driver = {
+ .name = "tegra-gpcdma",
+ .owner = THIS_MODULE,
+ .pm = &tegra_dma_dev_pm_ops,
+ .of_match_table = tegra_dma_of_match,
+ },
+ .probe = tegra_dma_probe,
+ .remove = tegra_dma_remove,
+};
+
+static int __init tegra_dmac_drvinit(void)
+{
+ return platform_driver_register(&tegra_dmac_driver);
+}
+fs_initcall(tegra_dmac_drvinit);
+
+static void __exit tegra_dmac_drvexit(void)
+{
+ platform_driver_unregister(&tegra_dmac_driver);
+}
+module_exit(tegra_dmac_drvexit);
+
+MODULE_ALIAS("platform:tegra-gpc-dma");
+MODULE_DESCRIPTION("NVIDIA Tegra GPC DMA Controller driver");
+MODULE_AUTHOR("Pavan Kunapuli <pkunapuli@nvidia.com>");
+MODULE_AUTHOR("Rajesh Gumasta <rgumasta@nvidia.com>");
+MODULE_LICENSE("GPL v2");
--
2.7.4