[v3,2/4] dmaengine: tegra: Add tegra gpcdma driver

Message ID	1630044294-21169-3-git-send-email-akhilrajeev@nvidia.com (mailing list archive)
State	Superseded
Headers	show Return-Path: <dmaengine-owner@kernel.org> Received-SPF: Pass (protection.outlook.com: domain of nvidia.com designates 216.228.112.32 as permitted sender) receiver=protection.outlook.com; client-ip=216.228.112.32; helo=mail.nvidia.com; From: Akhil R <akhilrajeev@nvidia.com> To: <rgumasta@nvidia.com> CC: <dan.j.williams@intel.com>, <dmaengine@vger.kernel.org>, <jonathanh@nvidia.com>, <kyarlagadda@nvidia.com>, <ldewangan@nvidia.com>, <linux-kernel@vger.kernel.org>, <linux-tegra@vger.kernel.org>, <p.zabel@pengutronix.de>, <thierry.reding@gmail.com>, <vkoul@kernel.org>, Akhil R <akhilrajeev@nvidia.com>, Pavan Kunapuli <pkunapuli@nvidia.com> Subject: [PATCH v3 2/4] dmaengine: tegra: Add tegra gpcdma driver Date: Fri, 27 Aug 2021 11:34:52 +0530 Message-ID: <1630044294-21169-3-git-send-email-akhilrajeev@nvidia.com> In-Reply-To: <1630044294-21169-1-git-send-email-akhilrajeev@nvidia.com> References: <MN2PR12MB41438B94148A6D522C056771A2A70@MN2PR12MB4143.namprd12.prod.outlook.com> <1630044294-21169-1-git-send-email-akhilrajeev@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk
Series	Add Nvidia Tegra GPC-DMA driver \| expand [v3,0/4] Add Nvidia Tegra GPC-DMA driver [v3,1/4] dt-bindings: dmaengine: Add doc for tegra gpcdma [v3,2/4] dmaengine: tegra: Add tegra gpcdma driver [v3,3/4] arm64: defconfig: tegra: Enable GPCDMA [v3,4/4] arm64: tegra: Add GPCDMA node for tegra186 and tegra194

On 27/08/2021 07:04, Akhil R wrote: > Adding GPC DMA controller driver for Tegra186 and Tegra194. The driver > supports dma transfers between memory to memory, IO peripheral to memory > and memory to IO peripheral. > > Signed-off-by: Pavan Kunapuli <pkunapuli@nvidia.com> > Signed-off-by: Rajesh Gumasta <rgumasta@nvidia.com> > Signed-off-by: Akhil R <akhilrajeev@nvidia.com> > --- > drivers/dma/Kconfig | 12 + > drivers/dma/Makefile | 1 + > drivers/dma/tegra-gpc-dma.c | 1343 +++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 1356 insertions(+) > create mode 100644 drivers/dma/tegra-gpc-dma.c > > diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig > index 39b5b46..9d1d93d 100644 > --- a/drivers/dma/Kconfig > +++ b/drivers/dma/Kconfig > @@ -632,6 +632,18 @@ 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 has multiple DMA channels 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 aa69094..943e8d7 100644 > --- a/drivers/dma/Makefile > +++ b/drivers/dma/Makefile > @@ -73,6 +73,7 @@ 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..d990121 > --- /dev/null > +++ b/drivers/dma/tegra-gpc-dma.c > @@ -0,0 +1,1343 @@ > +// 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/iopoll.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 GENMASK(25, 24) > +#define TEGRA_GPCDMA_CSR_FC_MODE_NO_MMIO \ > + FIELD_PREP(TEGRA_GPCDMA_CSR_FC_MODE, 0) > +#define TEGRA_GPCDMA_CSR_FC_MODE_ONE_MMIO \ > + FIELD_PREP(TEGRA_GPCDMA_CSR_FC_MODE, 1) > +#define TEGRA_GPCDMA_CSR_FC_MODE_TWO_MMIO \ > + FIELD_PREP(TEGRA_GPCDMA_CSR_FC_MODE, 2) > +#define TEGRA_GPCDMA_CSR_FC_MODE_FOUR_MMIO \ > + FIELD_PREP(TEGRA_GPCDMA_CSR_FC_MODE, 3) > + > +#define TEGRA_GPCDMA_CSR_DMA GENMASK(23, 21) > +#define TEGRA_GPCDMA_CSR_DMA_IO2MEM_NO_FC \ > + FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 0) > +#define TEGRA_GPCDMA_CSR_DMA_IO2MEM_FC \ > + FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 1) > +#define TEGRA_GPCDMA_CSR_DMA_MEM2IO_NO_FC \ > + FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 2) > +#define TEGRA_GPCDMA_CSR_DMA_MEM2IO_FC \ > + FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 3) > +#define TEGRA_GPCDMA_CSR_DMA_MEM2MEM \ > + FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 4) > +#define TEGRA_GPCDMA_CSR_DMA_FIXED_PAT \ > + FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 6) > + > +#define TEGRA_GPCDMA_CSR_REQ_SEL_MASK GENMASK(20, 16) > +#define TEGRA_GPCDMA_CSR_REQ_SEL_UNUSED \ > + FIELD_PREP(TEGRA_GPCDMA_CSR_REQ_SEL_MASK, 4) > +#define TEGRA_GPCDMA_CSR_IRQ_MASK BIT(15) > +#define TEGRA_GPCDMA_CSR_WEIGHT GENMASK(13, 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_SRC_PTR GENMASK(7, 0) > +#define TEGRA_GPCDMA_HIGH_ADDR_DST_PTR GENMASK(23, 16) > + > +/* MC sequence register */ > +#define TEGRA_GPCDMA_CHAN_MCSEQ 0x18 > +#define TEGRA_GPCDMA_MCSEQ_DATA_SWAP BIT(31) > +#define TEGRA_GPCDMA_MCSEQ_REQ_COUNT GENMASK(30, 25) > +#define TEGRA_GPCDMA_MCSEQ_BURST GENMASK(24, 23) > +#define TEGRA_GPCDMA_MCSEQ_BURST_2 \ > + FIELD_PREP(TEGRA_GPCDMA_MCSEQ_BURST, 0) > +#define TEGRA_GPCDMA_MCSEQ_BURST_16 \ > + FIELD_PREP(TEGRA_GPCDMA_MCSEQ_BURST, 3) > +#define TEGRA_GPCDMA_MCSEQ_WRAP1 GENMASK(22, 20) > +#define TEGRA_GPCDMA_MCSEQ_WRAP0 GENMASK(19, 17) > +#define TEGRA_GPCDMA_MCSEQ_WRAP_NONE 0 > + > +#define TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK GENMASK(13, 7) > +#define TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK GENMASK(6, 0) > + > +/* MMIO sequence register */ > +#define TEGRA_GPCDMA_CHAN_MMIOSEQ 0x01c > +#define TEGRA_GPCDMA_MMIOSEQ_DBL_BUF BIT(31) > +#define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH GENMASK(30, 28) > +#define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_8 \ > + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH, 0) > +#define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_16 \ > + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH, 1) > +#define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_32 \ > + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH, 2) > +#define TEGRA_GPCDMA_MMIOSEQ_DATA_SWAP BIT(27) > +#define TEGRA_GPCDMA_MMIOSEQ_BURST GENMASK(26, 23) > +#define TEGRA_GPCDMA_MMIOSEQ_BURST_1 \ > + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BURST, 0) > +#define TEGRA_GPCDMA_MMIOSEQ_BURST_2 \ > + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BURST, 1) > +#define TEGRA_GPCDMA_MMIOSEQ_BURST_4 \ > + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BURST, 3) > +#define TEGRA_GPCDMA_MMIOSEQ_BURST_8 \ > + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BURST, 7) > +#define TEGRA_GPCDMA_MMIOSEQ_BURST_16 \ > + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BURST, 15) > +#define TEGRA_GPCDMA_MMIOSEQ_MASTER_ID GENMASK(22, 19) > +#define TEGRA_GPCDMA_MMIOSEQ_WRAP_WORD GENMASK(18, 16) > +#define TEGRA_GPCDMA_MMIOSEQ_MMIO_PROT GENMASK(8, 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_desc: Tegra DMA descriptors which uses virt_dma_desc to > + * manage client request and 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_regs ch_regs; > +}; > + > +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; > + char name[30]; > + bool config_init; > + int id; > + int irq; > + unsigned int stream_id; > + unsigned long chan_base_offset; > + raw_spinlock_t lock; > + bool busy; > + bool is_pending; > + struct tegra_dma *tdma; > + dma_isr_handler isr_handler; > + int slave_id; > + struct dma_slave_config dma_sconfig; > +}; > + > +/* > + * 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; > + struct tegra_dma_channel channels[0]; > +}; > + > +static inline void tdc_write(struct tegra_dma_channel *tdc, > + u32 reg, u32 val) > +{ > + writel_relaxed(val, tdc->tdma->base_addr + tdc->chan_base_offset + reg); > +} > + > +static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg) > +{ > + return readl_relaxed(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) > +{ > + dev_dbg(tdc2dev(tdc), "DMA Channel %d name %s register dump:\n", > + tdc->id, tdc->name); > + dev_dbg(tdc2dev(tdc), "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) > + ); > + dev_dbg(tdc2dev(tdc), "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) > + ); > + dev_dbg(tdc2dev(tdc), "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); > + struct tegra_dma_channel *tdc = dma_desc->tdc; > + unsigned long flags; > + > + if (dma_desc) { > + raw_spin_lock_irqsave(&tdc->lock, flags); > + kfree(dma_desc); > + raw_spin_unlock_irqrestore(&tdc->lock, flags); > + } > +} I think that this can be simplified to simply ... static void tegra_dma_desc_free(struct virt_dma_desc *vd) { kfree(container_of(vd, struct tegra_dma_desc, vd)); } > + > +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 (tdc->dma_desc) { Any reason not to check config_init here instead? > + 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; How do you ensure that you are not trying to use an ID that is already being used? If you look at the tegra210-adma.c driver you will see that we have a bit mask for determining if the IDs are in used or not (see tx_requests_reserved and rx_requests_reserved). > + tdc->config_init = true; > + return 0; > +} > + > +static int tegra_dma_pause(struct tegra_dma_channel *tdc) > +{ > + u32 val; > + int ret; > + > + tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSRE, TEGRA_GPCDMA_CHAN_CSRE_PAUSE); > + > + /* Wait until busy bit is de-asserted */ > + ret = readl_relaxed_poll_timeout_atomic(tdc->tdma->base_addr + > + tdc->chan_base_offset + TEGRA_GPCDMA_CHAN_STATUS, > + val, > + !(val & TEGRA_GPCDMA_STATUS_BUSY), > + TEGRA_GPCDMA_BURST_COMPLETE_TIME, > + TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT); > + > + if (ret) > + dev_err(tdc2dev(tdc), "DMA pause timed out\n"); > + > + return ret; > +} > + > +static void tegra_dma_stop(struct tegra_dma_channel *tdc) > +{ > + u32 csr, status; > + > + csr = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSR); > + > + /* Disable interrupts */ > + csr &= ~TEGRA_GPCDMA_CSR_IE_EOC; > + > + /* 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_channel_regs *ch_regs = &tdc->dma_desc->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 virt_dma_desc *vdesc; > + > + if (tdc->is_pending) > + return; > + > + vdesc = vchan_next_desc(&tdc->vc); > + if (!vdesc) > + return; > + > + tdc->dma_desc = vd_to_tegra_dma_desc(vdesc); > + if (!tdc->dma_desc) > + return; > + > + list_del(&vdesc->node); > + > + tdc->is_pending = true; Is is_pending really needed? > + tdc->dma_desc->tdc = tdc; > + tegra_dma_start(tdc); I would combine this function and tegra_dma_start() into a single function called tegra_dma_start(). > + tdc->busy = true; > +} > + > +static void tegra_dma_abort_all(struct tegra_dma_channel *tdc) > +{ > + kfree(tdc->dma_desc); > + tdc->isr_handler = NULL; > +} > + > +static void handle_once_dma_done(struct tegra_dma_channel *tdc, > + bool to_terminate) This function name is not very descriptive. Maybe just tegra_dma_isr_callback(). > +{ > + struct tegra_dma_desc *dma_desc; > + > + tdc->busy = false; > + dma_desc = tdc->dma_desc; > + dma_desc->bytes_transferred += dma_desc->bytes_requested; > + > + vchan_cookie_complete(&tdc->dma_desc->vd); > + tdc->is_pending = false; > + kfree(tdc->dma_desc); > + > + if (to_terminate) > + 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; > + irqreturn_t ret = IRQ_NONE; > + unsigned int err_status; > + unsigned long status; > + > + raw_spin_lock(&tdc->lock); > + > + 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); > + } > + ret = IRQ_HANDLED; > + } > + > + raw_spin_unlock(&tdc->lock); > + return ret; > +} > + > +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 (!tdc->busy) > + if (vchan_issue_pending(&tdc->vc)) > + tdc_start_head_req(tdc); > + > + raw_spin_unlock_irqrestore(&tdc->lock, flags); > +} > + > +static void tegra_dma_reset_client(struct tegra_dma_channel *tdc) > +{ > + u32 csr = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSR); > + > + csr &= ~(TEGRA_GPCDMA_CSR_REQ_SEL_MASK); > + csr |= TEGRA_GPCDMA_CSR_REQ_SEL_UNUSED; > + 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); > + unsigned long wcount = 0; > + unsigned long status; > + unsigned long flags; > + bool was_busy; > + int err; > + > + raw_spin_lock_irqsave(&tdc->lock, flags); > + > + if (!tdc->dma_desc) { > + 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 > + */ > + > + if (readl_relaxed_poll_timeout_atomic(tdc->tdma->base_addr + > + tdc->chan_base_offset + > + TEGRA_GPCDMA_CHAN_STATUS, > + status, > + !(status & (TEGRA_GPCDMA_STATUS_CHANNEL_TX | > + TEGRA_GPCDMA_STATUS_CHANNEL_RX)), > + 5, > + TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT)) { > + dev_dbg(tdc2dev(tdc), "Timeout waiting for DMA burst completion!\n"); > + tegra_dma_dump_chan_regs(tdc); > + } I would be tempted to make the code in the 'else' clause tegra_dma_sw_pause(). Then you could have tegra_dma_hw_pause() and tegra_dma_sw_pause(). > + } > + > + 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 (tdc->dma_desc && was_busy) > + tdc->dma_desc->bytes_transferred += > + tdc->dma_desc->bytes_requested - (wcount * 4); > + > +skip_dma_stop: > + tegra_dma_abort_all(tdc); > + vchan_free_chan_resources(&tdc->vc); > + if (tdc->is_pending) { > + tdc->is_pending = false; > + kfree(tdc->dma_desc); > + } > + > + 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 = NULL; > + struct virt_dma_desc *vd; > + unsigned int residual; > + enum dma_status ret; > + unsigned long flags; > + > + 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; > + } > + > + vd = vchan_find_desc(&tdc->vc, cookie); > + if (vd) > + dma_desc = vd_to_tegra_dma_desc(vd); > + > + if (dma_desc) { > + residual = dma_desc->bytes_requested - > + (dma_desc->bytes_transferred % > + dma_desc->bytes_requested); > + dma_set_residue(txstate, residual); > + kfree(dma_desc); > + } else { > + dev_err(tdc2dev(tdc), "cookie %d is 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; > + default: > + dev_err(tdc2dev(tdc), "given slave bw is not supported\n"); > + return -EINVAL; > + } > +} > + > +static inline int get_burst_size_by_len(int len) > +{ > + int ret; > + > + switch (len) { > + case BIT(0) ... BIT(2): > + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_1; > + break; > + case BIT(3): > + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_2; > + break; > + case BIT(4): > + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_4; > + break; > + case BIT(5): > + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_8; > + break; > + default: > + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_16; > + break; > + } > + > + return ret; > +} > + > +static inline int get_burst_size(struct tegra_dma_channel *tdc, > + u32 burst_size, > + enum dma_slave_buswidth slave_bw, > + int len) > +{ > + int burst_mmio_width, burst_byte, ret; > + > + /* > + * 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; > + > + switch (burst_mmio_width) { > + case 0: > + ret = get_burst_size_by_len(len); > + break; > + case 1: > + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_1; > + break; > + case 2 ... 3: > + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_2; > + break; > + case 4 ... 7: > + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_4; > + break; > + case 8 ... 15: > + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_8; > + break; > + default: > + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_16; > + break; > + } > + > + return ret; > +} > + > +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; > + unsigned long csr, mc_seq; > + > + /* 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 |= FIELD_PREP(TEGRA_GPCDMA_CSR_WEIGHT, 1); > + > + mc_seq = tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ); > + /* retain stream-id and clean rest */ > + mc_seq &= TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK; > + > + /* Set the address wrapping */ > + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP0, > + TEGRA_GPCDMA_MCSEQ_WRAP_NONE); > + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP1, > + TEGRA_GPCDMA_MCSEQ_WRAP_NONE); > + > + /* Program outstanding MC requests */ > + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_REQ_COUNT, 1); > + /* Set burst size */ > + mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_16; > + > + dma_desc = kzalloc(sizeof(*dma_desc), GFP_NOWAIT); > + if (!dma_desc) > + 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; > + } > + > + dma_desc->bytes_requested += len; > + dma_desc->ch_regs.src_ptr = 0; > + dma_desc->ch_regs.dst_ptr = dest; > + dma_desc->ch_regs.high_addr_ptr = > + FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (dest >> 32)); > + dma_desc->ch_regs.fixed_pattern = value; > + /* Word count reg takes value as (N +1) words */ > + dma_desc->ch_regs.wcount = ((len - 4) >> 2); > + dma_desc->ch_regs.csr = csr; > + dma_desc->ch_regs.mmio_seq = 0; > + dma_desc->ch_regs.mc_seq = mc_seq; > + > + tdc->dma_desc = dma_desc; > + > + if (!tdc->isr_handler) > + tdc->isr_handler = handle_once_dma_done; Is this actually set to anything other than handle_once_dma_done? In not you can get rid of the function pointer completely. > + > + 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; > + unsigned long csr, mc_seq; > + > + /* 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 |= FIELD_PREP(TEGRA_GPCDMA_CSR_WEIGHT, 1); > + > + mc_seq = tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ); > + /* retain stream-id and clean rest */ > + mc_seq &= (TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK) | > + (TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK); > + > + /* Set the address wrapping */ > + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP0, > + TEGRA_GPCDMA_MCSEQ_WRAP_NONE); > + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP1, > + TEGRA_GPCDMA_MCSEQ_WRAP_NONE); > + > + /* Program outstanding MC requests */ > + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_REQ_COUNT, 1); > + /* Set burst size */ > + mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_16; > + > + dma_desc = kzalloc(sizeof(*dma_desc), GFP_NOWAIT); > + if (!dma_desc) > + 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; > + } > + > + dma_desc->bytes_requested += len; > + dma_desc->ch_regs.src_ptr = src; > + dma_desc->ch_regs.dst_ptr = dest; > + dma_desc->ch_regs.high_addr_ptr = > + FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_SRC_PTR, (src >> 32)); > + dma_desc->ch_regs.high_addr_ptr |= > + FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (dest >> 32)); > + /* Word count reg takes value as (N +1) words */ > + dma_desc->ch_regs.wcount = ((len - 4) >> 2); > + dma_desc->ch_regs.csr = csr; > + dma_desc->ch_regs.mmio_seq = 0; > + dma_desc->ch_regs.mc_seq = mc_seq; > + > + if (!tdc->isr_handler) > + tdc->isr_handler = handle_once_dma_done; > + > + 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); > + unsigned long csr, mc_seq, apb_ptr = 0, mmio_seq = 0; > + enum dma_slave_buswidth slave_bw; > + struct tegra_dma_desc *dma_desc; > + struct scatterlist *sg; > + u32 burst_size; > + unsigned int i; > + 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; > + > + /* Enable once or continuous mode */ > + csr |= TEGRA_GPCDMA_CSR_ONCE; > + /* Program the slave id in requestor select */ > + csr |= FIELD_PREP(TEGRA_GPCDMA_CSR_REQ_SEL_MASK, tdc->slave_id); > + /* Enable IRQ mask */ > + csr |= TEGRA_GPCDMA_CSR_IRQ_MASK; > + /* Configure default priority weight for the channel*/ > + csr |= FIELD_PREP(TEGRA_GPCDMA_CSR_WEIGHT, 1); > + > + /* 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_ID0_MASK; > + > + /* Set the address wrapping on both MC and MMIO side */ > + > + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP0, > + TEGRA_GPCDMA_MCSEQ_WRAP_NONE); > + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP1, > + TEGRA_GPCDMA_MCSEQ_WRAP_NONE); > + mmio_seq |= FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_WRAP_WORD, 1); > + > + /* Program 2 MC outstanding requests by default. */ > + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_REQ_COUNT, 1); > + > + /* 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(*dma_desc), GFP_NOWAIT); > + if (!dma_desc) > + 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; > + } > + > + mmio_seq |= get_burst_size(tdc, burst_size, slave_bw, len); > + dma_desc->bytes_requested += len; > + > + if (direction == DMA_MEM_TO_DEV) { > + dma_desc->ch_regs.src_ptr = mem; > + dma_desc->ch_regs.dst_ptr = apb_ptr; > + dma_desc->ch_regs.high_addr_ptr = > + FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_SRC_PTR, (mem >> 32)); > + } else if (direction == DMA_DEV_TO_MEM) { > + dma_desc->ch_regs.src_ptr = apb_ptr; > + dma_desc->ch_regs.dst_ptr = mem; > + dma_desc->ch_regs.high_addr_ptr = > + FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (mem >> 32)); > + } > + > + /* > + * Word count register takes input in words. Writing a value > + * of N into word count register means a req of (N+1) words. > + */ > + dma_desc->ch_regs.wcount = ((len - 4) >> 2); > + dma_desc->ch_regs.csr = csr; > + dma_desc->ch_regs.mmio_seq = mmio_seq; > + dma_desc->ch_regs.mc_seq = mc_seq; > + tdc->dma_desc = dma_desc; > + } > + > + /* > + * Make sure that mode should not be conflicting with currently > + * configured mode. > + */ > + if (!tdc->isr_handler) > + tdc->isr_handler = handle_once_dma_done; > + > + return vchan_tx_prep(&tdc->vc, &dma_desc->vd, flags); > +} > + > +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_chan_synchronize(struct dma_chan *dc) > +{ > + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); > + > + vchan_synchronize(&tdc->vc); > +} > + > +static void tegra_dma_free_chan_resources(struct dma_chan *dc) > +{ > + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); > + unsigned long flags; > + > + dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id); > + > + if (tdc->busy) > + tegra_dma_terminate_all(dc); > + > + tegra_dma_chan_synchronize(dc); > + > + tasklet_kill(&tdc->vc.task); > + raw_spin_lock_irqsave(&tdc->lock, flags); > + 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 tegra_dma_channel *tdc; > + struct dma_chan *chan; > + > + 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 = 31, > + .channel_reg_size = SZ_64K, > + .max_dma_count = SZ_1G, > + .hw_support_pause = false, > +}; > + > +static const struct tegra_dma_chip_data tegra194_dma_chip_data = { > + .nr_channels = 31, > + .channel_reg_size = SZ_64K, > + .max_dma_count = SZ_1G, > + .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_ID0_MASK); > + reg_val &= ~(TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK); > + > + reg_val |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK, stream_id); > + reg_val |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK, stream_id); > + > + tdc_write(tdc, TEGRA_GPCDMA_CHAN_MCSEQ, reg_val); > + return 0; > +} > + > +static int tegra_dma_probe(struct platform_device *pdev) > +{ > + const struct tegra_dma_chip_data *cdata = NULL; > + const unsigned int start_chan_idx = 1; What is this? > + unsigned int stream_id, i; > + struct tegra_dma *tdma; > + struct resource *res; > + int ret; > + > + cdata = of_device_get_match_data(&pdev->dev); > + > + ret = of_property_read_u32(pdev->dev.of_node, > + "nvidia,stream-id", &stream_id); Property not mentioned in the binding doc. > + if (ret) > + 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); > + > + tdma->base_addr = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(tdma->base_addr)) > + return PTR_ERR(tdma->base_addr); > + > + tdma->rst = devm_reset_control_get_exclusive(&pdev->dev, "gpcdma"); > + if (IS_ERR(tdma->rst)) { > + if (!(PTR_ERR(tdma->rst) == -EPROBE_DEFER)) > + dev_err(&pdev->dev, "Missing controller reset\n"); dev_err_probe() > + return PTR_ERR(tdma->rst); > + } > + reset_control_reset(tdma->rst); > + > + 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; Is this goto needed? > + } > + 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); > + > + /* program stream-id for this channel */ > + tegra_dma_program_sid(tdc, i, stream_id); > + tdc->stream_id = 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; > + tdma->dma_dev.device_synchronize = tegra_dma_chan_synchronize; > + tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; > + > + /* 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: > + return ret; > +} > + > +static int tegra_dma_remove(struct platform_device *pdev) > +{ > + struct tegra_dma *tdma = platform_get_drvdata(pdev); > + > + of_dma_controller_free(pdev->dev.of_node); > + dma_async_device_unregister(&tdma->dma_dev); > + > + return 0; > +} > + > +/* > + * Save and restore csr and channel register on pm_suspend > + * and pm_resume respectively > + */ > +static int __maybe_unused tegra_dma_pm_suspend(struct device *dev) > +{ > + struct tegra_dma *tdma = dev_get_drvdata(dev); > + unsigned long flags; > + unsigned int i; > + bool busy; > + > + for (i = 0; i < tdma->chip_data->nr_channels; i++) { > + struct tegra_dma_channel *tdc = &tdma->channels[i]; > + > + raw_spin_lock_irqsave(&tdc->lock, flags); > + busy = tdc->busy; > + raw_spin_unlock_irqrestore(&tdc->lock, flags); > + > + if (busy) { > + dev_err(tdma->dev, "channel %u busy\n", i); > + return -EBUSY; > + } > + } Do we need to ensure that no one attempts to start the DMA after it has been suspended? > + > + return 0; > +} > + > +static int __maybe_unused tegra_dma_pm_resume(struct device *dev) > +{ > + struct tegra_dma *tdma = dev_get_drvdata(dev); > + unsigned int i; > + > + reset_control_reset(tdma->rst); > + > + for (i = 0; i < tdma->chip_data->nr_channels; i++) { > + struct tegra_dma_channel *tdc = &tdma->channels[i]; > + > + tegra_dma_program_sid(tdc, i, tdc->stream_id); > + } > + > + return 0; > +} > + > +static const struct __maybe_unused dev_pm_ops tegra_dma_dev_pm_ops = { > + SET_SYSTEM_SLEEP_PM_OPS(tegra_dma_pm_suspend, tegra_dma_pm_resume) > +}; > + > +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, > +}; > + > +module_platform_driver(tegra_dmac_driver); > + > +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"); >

diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index 39b5b46..9d1d93d 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -632,6 +632,18 @@ 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 has multiple DMA channels 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 aa69094..943e8d7 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -73,6 +73,7 @@ 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..d990121 --- /dev/null +++ b/drivers/dma/tegra-gpc-dma.c @@ -0,0 +1,1343 @@ +// 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/iopoll.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 GENMASK(25, 24) +#define TEGRA_GPCDMA_CSR_FC_MODE_NO_MMIO \ + FIELD_PREP(TEGRA_GPCDMA_CSR_FC_MODE, 0) +#define TEGRA_GPCDMA_CSR_FC_MODE_ONE_MMIO \ + FIELD_PREP(TEGRA_GPCDMA_CSR_FC_MODE, 1) +#define TEGRA_GPCDMA_CSR_FC_MODE_TWO_MMIO \ + FIELD_PREP(TEGRA_GPCDMA_CSR_FC_MODE, 2) +#define TEGRA_GPCDMA_CSR_FC_MODE_FOUR_MMIO \ + FIELD_PREP(TEGRA_GPCDMA_CSR_FC_MODE, 3) + +#define TEGRA_GPCDMA_CSR_DMA GENMASK(23, 21) +#define TEGRA_GPCDMA_CSR_DMA_IO2MEM_NO_FC \ + FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 0) +#define TEGRA_GPCDMA_CSR_DMA_IO2MEM_FC \ + FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 1) +#define TEGRA_GPCDMA_CSR_DMA_MEM2IO_NO_FC \ + FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 2) +#define TEGRA_GPCDMA_CSR_DMA_MEM2IO_FC \ + FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 3) +#define TEGRA_GPCDMA_CSR_DMA_MEM2MEM \ + FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 4) +#define TEGRA_GPCDMA_CSR_DMA_FIXED_PAT \ + FIELD_PREP(TEGRA_GPCDMA_CSR_DMA, 6) + +#define TEGRA_GPCDMA_CSR_REQ_SEL_MASK GENMASK(20, 16) +#define TEGRA_GPCDMA_CSR_REQ_SEL_UNUSED \ + FIELD_PREP(TEGRA_GPCDMA_CSR_REQ_SEL_MASK, 4) +#define TEGRA_GPCDMA_CSR_IRQ_MASK BIT(15) +#define TEGRA_GPCDMA_CSR_WEIGHT GENMASK(13, 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_SRC_PTR GENMASK(7, 0) +#define TEGRA_GPCDMA_HIGH_ADDR_DST_PTR GENMASK(23, 16) + +/* MC sequence register */ +#define TEGRA_GPCDMA_CHAN_MCSEQ 0x18 +#define TEGRA_GPCDMA_MCSEQ_DATA_SWAP BIT(31) +#define TEGRA_GPCDMA_MCSEQ_REQ_COUNT GENMASK(30, 25) +#define TEGRA_GPCDMA_MCSEQ_BURST GENMASK(24, 23) +#define TEGRA_GPCDMA_MCSEQ_BURST_2 \ + FIELD_PREP(TEGRA_GPCDMA_MCSEQ_BURST, 0) +#define TEGRA_GPCDMA_MCSEQ_BURST_16 \ + FIELD_PREP(TEGRA_GPCDMA_MCSEQ_BURST, 3) +#define TEGRA_GPCDMA_MCSEQ_WRAP1 GENMASK(22, 20) +#define TEGRA_GPCDMA_MCSEQ_WRAP0 GENMASK(19, 17) +#define TEGRA_GPCDMA_MCSEQ_WRAP_NONE 0 + +#define TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK GENMASK(13, 7) +#define TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK GENMASK(6, 0) + +/* MMIO sequence register */ +#define TEGRA_GPCDMA_CHAN_MMIOSEQ 0x01c +#define TEGRA_GPCDMA_MMIOSEQ_DBL_BUF BIT(31) +#define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH GENMASK(30, 28) +#define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_8 \ + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH, 0) +#define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_16 \ + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH, 1) +#define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_32 \ + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH, 2) +#define TEGRA_GPCDMA_MMIOSEQ_DATA_SWAP BIT(27) +#define TEGRA_GPCDMA_MMIOSEQ_BURST GENMASK(26, 23) +#define TEGRA_GPCDMA_MMIOSEQ_BURST_1 \ + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BURST, 0) +#define TEGRA_GPCDMA_MMIOSEQ_BURST_2 \ + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BURST, 1) +#define TEGRA_GPCDMA_MMIOSEQ_BURST_4 \ + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BURST, 3) +#define TEGRA_GPCDMA_MMIOSEQ_BURST_8 \ + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BURST, 7) +#define TEGRA_GPCDMA_MMIOSEQ_BURST_16 \ + FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_BURST, 15) +#define TEGRA_GPCDMA_MMIOSEQ_MASTER_ID GENMASK(22, 19) +#define TEGRA_GPCDMA_MMIOSEQ_WRAP_WORD GENMASK(18, 16) +#define TEGRA_GPCDMA_MMIOSEQ_MMIO_PROT GENMASK(8, 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_desc: Tegra DMA descriptors which uses virt_dma_desc to + * manage client request and 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_regs ch_regs; +}; + +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; + char name[30]; + bool config_init; + int id; + int irq; + unsigned int stream_id; + unsigned long chan_base_offset; + raw_spinlock_t lock; + bool busy; + bool is_pending; + struct tegra_dma *tdma; + dma_isr_handler isr_handler; + int slave_id; + struct dma_slave_config dma_sconfig; +}; + +/* + * 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; + struct tegra_dma_channel channels[0]; +}; + +static inline void tdc_write(struct tegra_dma_channel *tdc, + u32 reg, u32 val) +{ + writel_relaxed(val, tdc->tdma->base_addr + tdc->chan_base_offset + reg); +} + +static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg) +{ + return readl_relaxed(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) +{ + dev_dbg(tdc2dev(tdc), "DMA Channel %d name %s register dump:\n", + tdc->id, tdc->name); + dev_dbg(tdc2dev(tdc), "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) + ); + dev_dbg(tdc2dev(tdc), "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) + ); + dev_dbg(tdc2dev(tdc), "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); + struct tegra_dma_channel *tdc = dma_desc->tdc; + unsigned long flags; + + if (dma_desc) { + raw_spin_lock_irqsave(&tdc->lock, flags); + kfree(dma_desc); + raw_spin_unlock_irqrestore(&tdc->lock, flags); + } +} + +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 (tdc->dma_desc) { + 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) +{ + u32 val; + int ret; + + tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSRE, TEGRA_GPCDMA_CHAN_CSRE_PAUSE); + + /* Wait until busy bit is de-asserted */ + ret = readl_relaxed_poll_timeout_atomic(tdc->tdma->base_addr + + tdc->chan_base_offset + TEGRA_GPCDMA_CHAN_STATUS, + val, + !(val & TEGRA_GPCDMA_STATUS_BUSY), + TEGRA_GPCDMA_BURST_COMPLETE_TIME, + TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT); + + if (ret) + dev_err(tdc2dev(tdc), "DMA pause timed out\n"); + + return ret; +} + +static void tegra_dma_stop(struct tegra_dma_channel *tdc) +{ + u32 csr, status; + + csr = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSR); + + /* Disable interrupts */ + csr &= ~TEGRA_GPCDMA_CSR_IE_EOC; + + /* 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_channel_regs *ch_regs = &tdc->dma_desc->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 virt_dma_desc *vdesc; + + if (tdc->is_pending) + return; + + vdesc = vchan_next_desc(&tdc->vc); + if (!vdesc) + return; + + tdc->dma_desc = vd_to_tegra_dma_desc(vdesc); + if (!tdc->dma_desc) + return; + + list_del(&vdesc->node); + + tdc->is_pending = true; + tdc->dma_desc->tdc = tdc; + tegra_dma_start(tdc); + tdc->busy = true; +} + +static void tegra_dma_abort_all(struct tegra_dma_channel *tdc) +{ + kfree(tdc->dma_desc); + tdc->isr_handler = NULL; +} + +static void handle_once_dma_done(struct tegra_dma_channel *tdc, + bool to_terminate) +{ + struct tegra_dma_desc *dma_desc; + + tdc->busy = false; + dma_desc = tdc->dma_desc; + dma_desc->bytes_transferred += dma_desc->bytes_requested; + + vchan_cookie_complete(&tdc->dma_desc->vd); + tdc->is_pending = false; + kfree(tdc->dma_desc); + + if (to_terminate) + 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; + irqreturn_t ret = IRQ_NONE; + unsigned int err_status; + unsigned long status; + + raw_spin_lock(&tdc->lock); + + 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); + } + ret = IRQ_HANDLED; + } + + raw_spin_unlock(&tdc->lock); + return ret; +} + +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 (!tdc->busy) + if (vchan_issue_pending(&tdc->vc)) + tdc_start_head_req(tdc); + + raw_spin_unlock_irqrestore(&tdc->lock, flags); +} + +static void tegra_dma_reset_client(struct tegra_dma_channel *tdc) +{ + u32 csr = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSR); + + csr &= ~(TEGRA_GPCDMA_CSR_REQ_SEL_MASK); + csr |= TEGRA_GPCDMA_CSR_REQ_SEL_UNUSED; + 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); + unsigned long wcount = 0; + unsigned long status; + unsigned long flags; + bool was_busy; + int err; + + raw_spin_lock_irqsave(&tdc->lock, flags); + + if (!tdc->dma_desc) { + 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 + */ + + if (readl_relaxed_poll_timeout_atomic(tdc->tdma->base_addr + + tdc->chan_base_offset + + TEGRA_GPCDMA_CHAN_STATUS, + status, + !(status & (TEGRA_GPCDMA_STATUS_CHANNEL_TX | + TEGRA_GPCDMA_STATUS_CHANNEL_RX)), + 5, + TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT)) { + dev_dbg(tdc2dev(tdc), "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 (tdc->dma_desc && was_busy) + tdc->dma_desc->bytes_transferred += + tdc->dma_desc->bytes_requested - (wcount * 4); + +skip_dma_stop: + tegra_dma_abort_all(tdc); + vchan_free_chan_resources(&tdc->vc); + if (tdc->is_pending) { + tdc->is_pending = false; + kfree(tdc->dma_desc); + } + + 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 = NULL; + struct virt_dma_desc *vd; + unsigned int residual; + enum dma_status ret; + unsigned long flags; + + 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; + } + + vd = vchan_find_desc(&tdc->vc, cookie); + if (vd) + dma_desc = vd_to_tegra_dma_desc(vd); + + if (dma_desc) { + residual = dma_desc->bytes_requested - + (dma_desc->bytes_transferred % + dma_desc->bytes_requested); + dma_set_residue(txstate, residual); + kfree(dma_desc); + } else { + dev_err(tdc2dev(tdc), "cookie %d is 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; + default: + dev_err(tdc2dev(tdc), "given slave bw is not supported\n"); + return -EINVAL; + } +} + +static inline int get_burst_size_by_len(int len) +{ + int ret; + + switch (len) { + case BIT(0) ... BIT(2): + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_1; + break; + case BIT(3): + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_2; + break; + case BIT(4): + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_4; + break; + case BIT(5): + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_8; + break; + default: + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_16; + break; + } + + return ret; +} + +static inline int get_burst_size(struct tegra_dma_channel *tdc, + u32 burst_size, + enum dma_slave_buswidth slave_bw, + int len) +{ + int burst_mmio_width, burst_byte, ret; + + /* + * 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; + + switch (burst_mmio_width) { + case 0: + ret = get_burst_size_by_len(len); + break; + case 1: + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_1; + break; + case 2 ... 3: + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_2; + break; + case 4 ... 7: + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_4; + break; + case 8 ... 15: + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_8; + break; + default: + ret = TEGRA_GPCDMA_MMIOSEQ_BURST_16; + break; + } + + return ret; +} + +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; + unsigned long csr, mc_seq; + + /* 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 |= FIELD_PREP(TEGRA_GPCDMA_CSR_WEIGHT, 1); + + mc_seq = tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ); + /* retain stream-id and clean rest */ + mc_seq &= TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK; + + /* Set the address wrapping */ + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP0, + TEGRA_GPCDMA_MCSEQ_WRAP_NONE); + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP1, + TEGRA_GPCDMA_MCSEQ_WRAP_NONE); + + /* Program outstanding MC requests */ + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_REQ_COUNT, 1); + /* Set burst size */ + mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_16; + + dma_desc = kzalloc(sizeof(*dma_desc), GFP_NOWAIT); + if (!dma_desc) + 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; + } + + dma_desc->bytes_requested += len; + dma_desc->ch_regs.src_ptr = 0; + dma_desc->ch_regs.dst_ptr = dest; + dma_desc->ch_regs.high_addr_ptr = + FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (dest >> 32)); + dma_desc->ch_regs.fixed_pattern = value; + /* Word count reg takes value as (N +1) words */ + dma_desc->ch_regs.wcount = ((len - 4) >> 2); + dma_desc->ch_regs.csr = csr; + dma_desc->ch_regs.mmio_seq = 0; + dma_desc->ch_regs.mc_seq = mc_seq; + + tdc->dma_desc = dma_desc; + + if (!tdc->isr_handler) + tdc->isr_handler = handle_once_dma_done; + + 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; + unsigned long csr, mc_seq; + + /* 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 |= FIELD_PREP(TEGRA_GPCDMA_CSR_WEIGHT, 1); + + mc_seq = tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ); + /* retain stream-id and clean rest */ + mc_seq &= (TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK) | + (TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK); + + /* Set the address wrapping */ + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP0, + TEGRA_GPCDMA_MCSEQ_WRAP_NONE); + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP1, + TEGRA_GPCDMA_MCSEQ_WRAP_NONE); + + /* Program outstanding MC requests */ + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_REQ_COUNT, 1); + /* Set burst size */ + mc_seq |= TEGRA_GPCDMA_MCSEQ_BURST_16; + + dma_desc = kzalloc(sizeof(*dma_desc), GFP_NOWAIT); + if (!dma_desc) + 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; + } + + dma_desc->bytes_requested += len; + dma_desc->ch_regs.src_ptr = src; + dma_desc->ch_regs.dst_ptr = dest; + dma_desc->ch_regs.high_addr_ptr = + FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_SRC_PTR, (src >> 32)); + dma_desc->ch_regs.high_addr_ptr |= + FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (dest >> 32)); + /* Word count reg takes value as (N +1) words */ + dma_desc->ch_regs.wcount = ((len - 4) >> 2); + dma_desc->ch_regs.csr = csr; + dma_desc->ch_regs.mmio_seq = 0; + dma_desc->ch_regs.mc_seq = mc_seq; + + if (!tdc->isr_handler) + tdc->isr_handler = handle_once_dma_done; + + 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); + unsigned long csr, mc_seq, apb_ptr = 0, mmio_seq = 0; + enum dma_slave_buswidth slave_bw; + struct tegra_dma_desc *dma_desc; + struct scatterlist *sg; + u32 burst_size; + unsigned int i; + 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; + + /* Enable once or continuous mode */ + csr |= TEGRA_GPCDMA_CSR_ONCE; + /* Program the slave id in requestor select */ + csr |= FIELD_PREP(TEGRA_GPCDMA_CSR_REQ_SEL_MASK, tdc->slave_id); + /* Enable IRQ mask */ + csr |= TEGRA_GPCDMA_CSR_IRQ_MASK; + /* Configure default priority weight for the channel*/ + csr |= FIELD_PREP(TEGRA_GPCDMA_CSR_WEIGHT, 1); + + /* 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_ID0_MASK; + + /* Set the address wrapping on both MC and MMIO side */ + + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP0, + TEGRA_GPCDMA_MCSEQ_WRAP_NONE); + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_WRAP1, + TEGRA_GPCDMA_MCSEQ_WRAP_NONE); + mmio_seq |= FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_WRAP_WORD, 1); + + /* Program 2 MC outstanding requests by default. */ + mc_seq |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_REQ_COUNT, 1); + + /* 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(*dma_desc), GFP_NOWAIT); + if (!dma_desc) + 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; + } + + mmio_seq |= get_burst_size(tdc, burst_size, slave_bw, len); + dma_desc->bytes_requested += len; + + if (direction == DMA_MEM_TO_DEV) { + dma_desc->ch_regs.src_ptr = mem; + dma_desc->ch_regs.dst_ptr = apb_ptr; + dma_desc->ch_regs.high_addr_ptr = + FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_SRC_PTR, (mem >> 32)); + } else if (direction == DMA_DEV_TO_MEM) { + dma_desc->ch_regs.src_ptr = apb_ptr; + dma_desc->ch_regs.dst_ptr = mem; + dma_desc->ch_regs.high_addr_ptr = + FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (mem >> 32)); + } + + /* + * Word count register takes input in words. Writing a value + * of N into word count register means a req of (N+1) words. + */ + dma_desc->ch_regs.wcount = ((len - 4) >> 2); + dma_desc->ch_regs.csr = csr; + dma_desc->ch_regs.mmio_seq = mmio_seq; + dma_desc->ch_regs.mc_seq = mc_seq; + tdc->dma_desc = dma_desc; + } + + /* + * Make sure that mode should not be conflicting with currently + * configured mode. + */ + if (!tdc->isr_handler) + tdc->isr_handler = handle_once_dma_done; + + return vchan_tx_prep(&tdc->vc, &dma_desc->vd, flags); +} + +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_chan_synchronize(struct dma_chan *dc) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + + vchan_synchronize(&tdc->vc); +} + +static void tegra_dma_free_chan_resources(struct dma_chan *dc) +{ + struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); + unsigned long flags; + + dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id); + + if (tdc->busy) + tegra_dma_terminate_all(dc); + + tegra_dma_chan_synchronize(dc); + + tasklet_kill(&tdc->vc.task); + raw_spin_lock_irqsave(&tdc->lock, flags); + 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 tegra_dma_channel *tdc; + struct dma_chan *chan; + + 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 = 31, + .channel_reg_size = SZ_64K, + .max_dma_count = SZ_1G, + .hw_support_pause = false, +}; + +static const struct tegra_dma_chip_data tegra194_dma_chip_data = { + .nr_channels = 31, + .channel_reg_size = SZ_64K, + .max_dma_count = SZ_1G, + .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_ID0_MASK); + reg_val &= ~(TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK); + + reg_val |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK, stream_id); + reg_val |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK, stream_id); + + tdc_write(tdc, TEGRA_GPCDMA_CHAN_MCSEQ, reg_val); + return 0; +} + +static int tegra_dma_probe(struct platform_device *pdev) +{ + const struct tegra_dma_chip_data *cdata = NULL; + const unsigned int start_chan_idx = 1; + unsigned int stream_id, i; + struct tegra_dma *tdma; + struct resource *res; + int ret; + + cdata = of_device_get_match_data(&pdev->dev); + + ret = of_property_read_u32(pdev->dev.of_node, + "nvidia,stream-id", &stream_id); + if (ret) + 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); + + tdma->base_addr = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(tdma->base_addr)) + return PTR_ERR(tdma->base_addr); + + tdma->rst = devm_reset_control_get_exclusive(&pdev->dev, "gpcdma"); + if (IS_ERR(tdma->rst)) { + if (!(PTR_ERR(tdma->rst) == -EPROBE_DEFER)) + dev_err(&pdev->dev, "Missing controller reset\n"); + return PTR_ERR(tdma->rst); + } + reset_control_reset(tdma->rst); + + 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); + + /* program stream-id for this channel */ + tegra_dma_program_sid(tdc, i, stream_id); + tdc->stream_id = 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; + tdma->dma_dev.device_synchronize = tegra_dma_chan_synchronize; + tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; + + /* 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: + return ret; +} + +static int tegra_dma_remove(struct platform_device *pdev) +{ + struct tegra_dma *tdma = platform_get_drvdata(pdev); + + of_dma_controller_free(pdev->dev.of_node); + dma_async_device_unregister(&tdma->dma_dev); + + return 0; +} + +/* + * Save and restore csr and channel register on pm_suspend + * and pm_resume respectively + */ +static int __maybe_unused tegra_dma_pm_suspend(struct device *dev) +{ + struct tegra_dma *tdma = dev_get_drvdata(dev); + unsigned long flags; + unsigned int i; + bool busy; + + for (i = 0; i < tdma->chip_data->nr_channels; i++) { + struct tegra_dma_channel *tdc = &tdma->channels[i]; + + raw_spin_lock_irqsave(&tdc->lock, flags); + busy = tdc->busy; + raw_spin_unlock_irqrestore(&tdc->lock, flags); + + if (busy) { + dev_err(tdma->dev, "channel %u busy\n", i); + return -EBUSY; + } + } + + return 0; +} + +static int __maybe_unused tegra_dma_pm_resume(struct device *dev) +{ + struct tegra_dma *tdma = dev_get_drvdata(dev); + unsigned int i; + + reset_control_reset(tdma->rst); + + for (i = 0; i < tdma->chip_data->nr_channels; i++) { + struct tegra_dma_channel *tdc = &tdma->channels[i]; + + tegra_dma_program_sid(tdc, i, tdc->stream_id); + } + + return 0; +} + +static const struct __maybe_unused dev_pm_ops tegra_dma_dev_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(tegra_dma_pm_suspend, tegra_dma_pm_resume) +}; + +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, +}; + +module_platform_driver(tegra_dmac_driver); + +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");

[v3,2/4] dmaengine: tegra: Add tegra gpcdma driver

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