From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932261AbaAWRwZ (ORCPT ); Thu, 23 Jan 2014 12:52:25 -0500 Received: from mail-lb0-f182.google.com ([209.85.217.182]:53162 "EHLO mail-lb0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753831AbaAWRwW (ORCPT ); Thu, 23 Jan 2014 12:52:22 -0500 MIME-Version: 1.0 In-Reply-To: <1390483954.7619.79.camel@smile> References: <1390409565-4200-1-git-send-email-sthokal@xilinx.com> <1390409565-4200-2-git-send-email-sthokal@xilinx.com> <1390483954.7619.79.camel@smile> Date: Thu, 23 Jan 2014 23:22:20 +0530 X-Google-Sender-Auth: CtZYdEbdK4eHBiSaEb4Q7b0ozbg Message-ID: Subject: Re: [PATCH v2] dma: Add Xilinx AXI Video Direct Memory Access Engine driver support From: Srikanth Thokala To: Andy Shevchenko Cc: Srikanth Thokala , dan.j.williams@intel.com, vinod.koul@intel.com, michal.simek@xilinx.com, Grant Likely , robh+dt@kernel.org, linux-arm-kernel@lists.infradead.org, "linux-kernel@vger.kernel.org" , devicetree@vger.kernel.org, dmaengine@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Andy, On Thu, Jan 23, 2014 at 7:02 PM, Andy Shevchenko wrote: > On Wed, 2014-01-22 at 22:22 +0530, Srikanth Thokala wrote: >> This is the driver for the AXI Video Direct Memory Access (AXI >> VDMA) core, which is a soft Xilinx IP core that provides high- >> bandwidth direct memory access between memory and AXI4-Stream >> type video target peripherals. The core provides efficient two >> dimensional DMA operations with independent asynchronous read >> and write channel operation. >> >> This module works on Zynq (ARM Based SoC) and Microblaze platforms. > > Few comments below. Ok, > >> >> Signed-off-by: Srikanth Thokala >> --- >> NOTE: >> 1. Created a separate directory 'dma/xilinx' as Xilinx has two more >> DMA IPs and we are also planning to upstream these drivers soon. >> 2. Rebased on v3.13.0-rc8 >> >> Changes in v2: >> - Removed DMA Test client module from the patchset as suggested >> by Andy Shevchenko >> - Removed device-id DT property, as suggested by Arnd Bergmann >> - Properly documented DT bindings as suggested by Arnd Bergmann >> - Returning with error, if registration of DMA to node fails >> - Fixed typo errors >> - Used BIT() macro at applicable places >> - Added missing header file to the patchset >> - Changed copyright year to include 2014 >> --- >> .../devicetree/bindings/dma/xilinx/xilinx_vdma.txt | 75 + >> drivers/dma/Kconfig | 14 + >> drivers/dma/Makefile | 1 + >> drivers/dma/xilinx/Makefile | 1 + >> drivers/dma/xilinx/xilinx_vdma.c | 1486 ++++++++++++++++++++ >> include/linux/amba/xilinx_dma.h | 50 + >> 6 files changed, 1627 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/dma/xilinx/xilinx_vdma.txt >> create mode 100644 drivers/dma/xilinx/Makefile >> create mode 100644 drivers/dma/xilinx/xilinx_vdma.c >> create mode 100644 include/linux/amba/xilinx_dma.h >> >> diff --git a/Documentation/devicetree/bindings/dma/xilinx/xilinx_vdma.txt b/Documentation/devicetree/bindings/dma/xilinx/xilinx_vdma.txt >> new file mode 100644 >> index 0000000..ab8be1a >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/dma/xilinx/xilinx_vdma.txt >> @@ -0,0 +1,75 @@ >> +Xilinx AXI VDMA engine, it does transfers between memory and video devices. >> +It can be configured to have one channel or two channels. If configured >> +as two channels, one is to transmit to the video device and another is >> +to receive from the video device. >> + >> +Required properties: >> +- compatible: Should be "xlnx,axi-vdma-1.00.a" >> +- #dma-cells: Should be <1>, see "dmas" property below >> +- reg: Should contain VDMA registers location and length. >> +- xlnx,num-fstores: Should be the number of framebuffers as configured in h/w. >> +- dma-channel child node: Should have atleast one channel and can have upto >> + two channels per device. This node specifies the properties of each >> + DMA channel (see child node properties below). >> + >> +Optional properties: >> +- xlnx,include-sg: Tells whether configured for Scatter-mode in >> + the hardware. >> +- xlnx,flush-fsync: Tells whether which channel to Flush on Frame sync. >> + It takes following values: >> + {1}, flush both channels >> + {2}, flush mm2s channel >> + {3}, flush s2mm channel >> + >> +Required child node properties: >> +- compatible: It should be either "xlnx,axi-vdma-mm2s-channel" or >> + "xlnx,axi-vdma-s2mm-channel". >> +- interrupts: Should contain per channel VDMA interrupts. >> +- xlnx,data-width: Should contain the stream data width, take values >> + {32,64...1024}. >> + >> +Option child node properties: >> +- xlnx,include-dre: Tells whether hardware is configured for Data >> + Realignment Engine. >> +- xlnx,genlock-mode: Tells whether Genlock synchronization is >> + enabled/disabled in hardware. >> + >> +Example: >> +++++++++ >> + >> +axi_vdma_0: axivdma@40030000 { >> + compatible = "xlnx,axi-vdma-1.00.a"; >> + #dma_cells = <1>; >> + reg = < 0x40030000 0x10000 >; >> + xlnx,num-fstores = <0x8>; >> + xlnx,flush-fsync = <0x1>; >> + dma-channel@40030000 { >> + compatible = "xlnx,axi-vdma-mm2s-channel"; >> + interrupts = < 0 54 4 >; >> + xlnx,datawidth = <0x40>; >> + } ; >> + dma-channel@40030030 { >> + compatible = "xlnx,axi-vdma-s2mm-channel"; >> + interrupts = < 0 53 4 >; >> + xlnx,datawidth = <0x40>; >> + } ; >> +} ; >> + >> + >> +* DMA client >> + >> +Required properties: >> +- dmas: a list of <[Video DMA device phandle] [Channel ID]> pairs, >> + where Channel ID is '0' for write/tx and '1' for read/rx >> + channel. >> +- dma-names: a list of DMA channel names, one per "dmas" entry >> + >> +Example: >> +++++++++ >> + >> +vdmatest_0: vdmatest@0 { >> + compatible ="xlnx,axi-vdma-test-1.00.a"; >> + dmas = <&axi_vdma_0 0 >> + &axi_vdma_0 1>; >> + dma-names = "vdma0", "vdma1"; >> +} ; >> diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig >> index c823daa..2a74651 100644 >> --- a/drivers/dma/Kconfig >> +++ b/drivers/dma/Kconfig >> @@ -334,6 +334,20 @@ config K3_DMA >> Support the DMA engine for Hisilicon K3 platform >> devices. >> >> +config XILINX_VDMA >> + tristate "Xilinx AXI VDMA Engine" >> + depends on (ARCH_ZYNQ || MICROBLAZE) >> + select DMA_ENGINE >> + help >> + Enable support for Xilinx AXI VDMA Soft IP. >> + >> + This engine provides high-bandwidth direct memory access >> + between memory and AXI4-Stream video type target >> + peripherals including peripherals which support AXI4- >> + Stream Video Protocol. It has two stream interfaces/ >> + channels, Memory Mapped to Stream (MM2S) and Stream to >> + Memory Mapped (S2MM) for the data transfers. >> + >> config DMA_ENGINE >> bool >> >> diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile >> index 0ce2da9..d84130b 100644 >> --- a/drivers/dma/Makefile >> +++ b/drivers/dma/Makefile >> @@ -42,3 +42,4 @@ obj-$(CONFIG_MMP_PDMA) += mmp_pdma.o >> obj-$(CONFIG_DMA_JZ4740) += dma-jz4740.o >> obj-$(CONFIG_TI_CPPI41) += cppi41.o >> obj-$(CONFIG_K3_DMA) += k3dma.o >> +obj-y += xilinx/ >> diff --git a/drivers/dma/xilinx/Makefile b/drivers/dma/xilinx/Makefile >> new file mode 100644 >> index 0000000..3c4e9f2 >> --- /dev/null >> +++ b/drivers/dma/xilinx/Makefile >> @@ -0,0 +1 @@ >> +obj-$(CONFIG_XILINX_VDMA) += xilinx_vdma.o >> diff --git a/drivers/dma/xilinx/xilinx_vdma.c b/drivers/dma/xilinx/xilinx_vdma.c >> new file mode 100644 >> index 0000000..4c0d04c >> --- /dev/null >> +++ b/drivers/dma/xilinx/xilinx_vdma.c >> @@ -0,0 +1,1486 @@ >> +/* >> + * DMA driver for Xilinx Video DMA Engine >> + * >> + * Copyright (C) 2010-2014 Xilinx, Inc. All rights reserved. >> + * >> + * Based on the Freescale DMA driver. >> + * >> + * Description: >> + * The AXI Video Direct Memory Access (AXI VDMA) core is a soft Xilinx IP >> + * core that provides high-bandwidth direct memory access between memory >> + * and AXI4-Stream type video target peripherals. The core provides efficient >> + * two dimensional DMA operations with independent asynchronous read (S2MM) >> + * and write (MM2S) channel operation. It can be configured to have either >> + * one channel or two channels. If configured as two channels, one is to >> + * transmit to the video device (MM2S) and another is to receive from the >> + * video device (S2MM). Initialization, status, interrupt and management >> + * registers are accessed through an AXI4-Lite slave interface. >> + * >> + * This program is free software: you can redistribute it and/or modify >> + * it under the terms of the GNU General Public License as published by >> + * the Free Software Foundation, either version 2 of the License, or >> + * (at your option) any later version. >> + */ >> + >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> + >> +/* Register/Descriptor Offsets */ >> +#define XILINX_VDMA_MM2S_CTRL_OFFSET 0x0000 >> +#define XILINX_VDMA_S2MM_CTRL_OFFSET 0x0030 >> +#define XILINX_VDMA_MM2S_DESC_OFFSET 0x0050 >> +#define XILINX_VDMA_S2MM_DESC_OFFSET 0x00a0 >> + >> +/* Control Registers */ >> +#define XILINX_VDMA_REG_DMACR 0x0000 >> +#define XILINX_VDMA_DMACR_DELAY_MAX 0xff >> +#define XILINX_VDMA_DMACR_DELAY_SHIFT 24 >> +#define XILINX_VDMA_DMACR_FRAME_COUNT_MAX 0xff >> +#define XILINX_VDMA_DMACR_FRAME_COUNT_SHIFT 16 >> +#define XILINX_VDMA_DMACR_ERR_IRQ BIT(14) >> +#define XILINX_VDMA_DMACR_DLY_CNT_IRQ BIT(13) >> +#define XILINX_VDMA_DMACR_FRM_CNT_IRQ BIT(12) >> +#define XILINX_VDMA_DMACR_MASTER_SHIFT 8 >> +#define XILINX_VDMA_DMACR_FSYNCSRC_SHIFT 5 >> +#define XILINX_VDMA_DMACR_FRAMECNT_EN BIT(4) >> +#define XILINX_VDMA_DMACR_GENLOCK_EN BIT(3) >> +#define XILINX_VDMA_DMACR_RESET BIT(2) >> +#define XILINX_VDMA_DMACR_CIRC_EN BIT(1) >> +#define XILINX_VDMA_DMACR_RUNSTOP BIT(0) >> +#define XILINX_VDMA_DMACR_DELAY_MASK \ >> + (XILINX_VDMA_DMACR_DELAY_MAX << \ >> + XILINX_VDMA_DMACR_DELAY_SHIFT) >> +#define XILINX_VDMA_DMACR_FRAME_COUNT_MASK \ >> + (XILINX_VDMA_DMACR_FRAME_COUNT_MAX << \ >> + XILINX_VDMA_DMACR_FRAME_COUNT_SHIFT) >> +#define XILINX_VDMA_DMACR_MASTER_MASK \ >> + (0xf << XILINX_VDMA_DMACR_MASTER_SHIFT) >> +#define XILINX_VDMA_DMACR_FSYNCSRC_MASK \ >> + (3 << XILINX_VDMA_DMACR_FSYNCSRC_SHIFT) >> + >> +#define XILINX_VDMA_REG_DMASR 0x0004 >> +#define XILINX_VDMA_DMASR_DELAY_SHIFT 24 >> +#define XILINX_VDMA_DMASR_FRAME_COUNT_SHIFT 16 >> +#define XILINX_VDMA_DMASR_EOL_LATE_ERR BIT(15) >> +#define XILINX_VDMA_DMASR_ERR_IRQ BIT(14) >> +#define XILINX_VDMA_DMASR_DLY_CNT_IRQ BIT(13) >> +#define XILINX_VDMA_DMASR_FRM_CNT_IRQ BIT(12) >> +#define XILINX_VDMA_DMASR_SOF_LATE_ERR BIT(11) >> +#define XILINX_VDMA_DMASR_SG_DEC_ERR BIT(10) >> +#define XILINX_VDMA_DMASR_SG_SLV_ERR BIT(9) >> +#define XILINX_VDMA_DMASR_EOF_EARLY_ERR BIT(8) >> +#define XILINX_VDMA_DMASR_SOF_EARLY_ERR BIT(7) >> +#define XILINX_VDMA_DMASR_DMA_DEC_ERR BIT(6) >> +#define XILINX_VDMA_DMASR_DMA_SLAVE_ERR BIT(5) >> +#define XILINX_VDMA_DMASR_DMA_INT_ERR BIT(4) >> +#define XILINX_VDMA_DMASR_IDLE BIT(1) >> +#define XILINX_VDMA_DMASR_HALTED BIT(0) >> + >> +#define XILINX_VDMA_DMASR_DELAY_MASK \ >> + (0xff << XILINX_VDMA_DMASR_DELAY_SHIFT) >> +#define XILINX_VDMA_DMASR_FRAME_COUNT_MASK \ >> + (0xff << XILINX_VDMA_DMASR_FRAME_COUNT_SHIFT) > > Does 0xff require to be a separate definition in both above cases? Ok, will reuse DELAY/FRAME_MAX masks. > >> + >> +#define XILINX_VDMA_REG_CURDESC 0x0008 >> +#define XILINX_VDMA_REG_TAILDESC 0x0010 >> +#define XILINX_VDMA_REG_REG_INDEX 0x0014 >> +#define XILINX_VDMA_REG_FRMSTORE 0x0018 >> +#define XILINX_VDMA_REG_THRESHOLD 0x001c >> +#define XILINX_VDMA_REG_FRMPTR_STS 0x0024 >> +#define XILINX_VDMA_REG_PARK_PTR 0x0028 >> +#define XILINX_VDMA_PARK_PTR_WR_REF_SHIFT 8 >> +#define XILINX_VDMA_PARK_PTR_RD_REF_SHIFT 0 >> +#define XILINX_VDMA_REG_VDMA_VERSION 0x002c >> + >> +/* Register Direct Mode Registers */ >> +#define XILINX_VDMA_REG_VSIZE 0x0000 >> +#define XILINX_VDMA_REG_HSIZE 0x0004 >> + >> +#define XILINX_VDMA_REG_FRMDLY_STRIDE 0x0008 >> +#define XILINX_VDMA_FRMDLY_STRIDE_FRMDLY_SHIFT 24 >> +#define XILINX_VDMA_FRMDLY_STRIDE_STRIDE_SHIFT 0 >> +#define XILINX_VDMA_FRMDLY_STRIDE_FRMDLY_MASK \ >> + (0x1f << \ >> + XILINX_VDMA_FRMDLY_STRIDE_FRMDLY_SHIFT) >> +#define XILINX_VDMA_FRMDLY_STRIDE_STRIDE_MASK \ >> + (0xffff << \ >> + XILINX_VDMA_FRMDLY_STRIDE_STRIDE_MASK) >> + >> +#define XILINX_VDMA_REG_START_ADDRESS(n) (0x000c + 4 * (n)) >> + >> +/* Hw specific definitions */ > > HW or Hardware Ok. > >> +#define XILINX_VDMA_MAX_CHANS_PER_DEVICE 0x2 >> + >> +#define XILINX_VDMA_DMAXR_ALL_IRQ_MASK (XILINX_VDMA_DMASR_FRM_CNT_IRQ | \ >> + XILINX_VDMA_DMASR_DLY_CNT_IRQ | \ >> + XILINX_VDMA_DMASR_ERR_IRQ) >> + >> +#define XILINX_VDMA_DMASR_ALL_ERR_MASK (XILINX_VDMA_DMASR_EOL_LATE_ERR | \ >> + XILINX_VDMA_DMASR_SOF_LATE_ERR | \ >> + XILINX_VDMA_DMASR_SG_DEC_ERR | \ >> + XILINX_VDMA_DMASR_SG_SLV_ERR | \ >> + XILINX_VDMA_DMASR_EOF_EARLY_ERR | \ >> + XILINX_VDMA_DMASR_SOF_EARLY_ERR | \ >> + XILINX_VDMA_DMASR_DMA_DEC_ERR | \ >> + XILINX_VDMA_DMASR_DMA_SLAVE_ERR | \ >> + XILINX_VDMA_DMASR_DMA_INT_ERR) >> + >> +/* >> + * Recoverable errors are DMA Internal error, SOF Early, EOF Early and SOF Late. >> + * They are only recoverable when C_FLUSH_ON_FSYNC is enabled in the h/w system. >> + */ >> +#define XILINX_VDMA_DMASR_ERR_RECOVER_MASK \ >> + (XILINX_VDMA_DMASR_SOF_LATE_ERR | \ > > Do you need so many tabs for an indentation here and in other places? > May be better to keep some style here (I mean on which line you start > the value of the definition). Ok. > >> + XILINX_VDMA_DMASR_EOF_EARLY_ERR | \ >> + XILINX_VDMA_DMASR_SOF_EARLY_ERR | \ >> + XILINX_VDMA_DMASR_DMA_INT_ERR) >> + >> +/* Axi VDMA Flush on Fsync bits */ >> +#define XILINX_VDMA_FLUSH_S2MM 3 >> +#define XILINX_VDMA_FLUSH_MM2S 2 >> +#define XILINX_VDMA_FLUSH_BOTH 1 >> + >> +/* Delay loop counter to prevent hardware failure */ >> +#define XILINX_VDMA_LOOP_COUNT 1000000 >> + >> +/** >> + * struct xilinx_vdma_desc_hw - Hardware Descriptor >> + * @next_desc: Next Descriptor Pointer @0x00 >> + * @pad1: Reserved @0x04 >> + * @buf_addr: Buffer address @0x08 >> + * @pad2: Reserved @0x0C >> + * @vsize: Vertical Size @0x10 >> + * @hsize: Horizontal Size @0x14 >> + * @stride: Number of bytes between the first >> + * pixels of each horizontal line @0x18 >> + */ >> +struct xilinx_vdma_desc_hw { >> + u32 next_desc; >> + u32 pad1; >> + u32 buf_addr; >> + u32 pad2; >> + u32 vsize; >> + u32 hsize; >> + u32 stride; >> +} __aligned(64); >> + >> +/** >> + * struct xilinx_vdma_tx_segment - Descriptor segment >> + * @hw: Hardware descriptor >> + * @node: Node in the descriptor segments list >> + * @cookie: Segment cookie >> + * @phys: Physical address of segment >> + */ >> +struct xilinx_vdma_tx_segment { >> + struct xilinx_vdma_desc_hw hw; >> + struct list_head node; >> + dma_cookie_t cookie; >> + dma_addr_t phys; >> +} __aligned(64); >> + >> +/** >> + * struct xilinx_vdma_tx_descriptor - Per Transaction structure >> + * @async_tx: Async transaction descriptor >> + * @segments: TX segments list >> + * @node: Node in the channel descriptors list >> + */ >> +struct xilinx_vdma_tx_descriptor { >> + struct dma_async_tx_descriptor async_tx; >> + struct list_head segments; >> + struct list_head node; >> +}; >> + >> +#define to_vdma_tx_descriptor(tx) \ >> + container_of(tx, struct xilinx_vdma_tx_descriptor, async_tx) >> + >> +/** >> + * struct xilinx_vdma_chan - Driver specific VDMA channel structure >> + * @xdev: Driver specific device structure >> + * @ctrl_offset: Control registers offset >> + * @desc_offset: TX descriptor registers offset >> + * @completed_cookie: Maximum cookie completed >> + * @cookie: The current cookie >> + * @lock: Descriptor operation lock >> + * @pending_list: Descriptors waiting >> + * @active_desc: Active descriptor >> + * @done_list: Complete descriptors >> + * @common: DMA common channel >> + * @desc_pool: Descriptors pool >> + * @dev: The dma device >> + * @irq: Channel IRQ >> + * @id: Channel ID >> + * @direction: Transfer direction >> + * @num_frms: Number of frames >> + * @has_sg: Support scatter transfers >> + * @genlock: Support genlock mode >> + * @err: Channel has errors >> + * @tasklet: Cleanup work after irq >> + * @config: Device configuration info >> + * @flush_on_fsync: Flush on Frame sync >> + */ >> +struct xilinx_vdma_chan { >> + struct xilinx_vdma_device *xdev; >> + u32 ctrl_offset; >> + u32 desc_offset; >> + dma_cookie_t completed_cookie; >> + dma_cookie_t cookie; >> + spinlock_t lock; >> + struct list_head pending_list; >> + struct xilinx_vdma_tx_descriptor *active_desc; >> + struct list_head done_list; >> + struct dma_chan common; >> + struct dma_pool *desc_pool; >> + struct device *dev; >> + int irq; >> + int id; >> + enum dma_transfer_direction direction; >> + int num_frms; >> + bool has_sg; >> + bool genlock; >> + bool err; >> + struct tasklet_struct tasklet; >> + struct xilinx_vdma_config config; >> + bool flush_on_fsync; >> +}; >> + >> +/** >> + * struct xilinx_vdma_device - VDMA device structure >> + * @regs: I/O mapped base address >> + * @dev: Device Structure >> + * @common: DMA device structure >> + * @chan: Driver specific VDMA channel >> + * @has_sg: Specifies whether Scatter-Gather is present or not >> + * @flush_on_fsync: Flush on frame sync >> + */ >> +struct xilinx_vdma_device { >> + void __iomem *regs; >> + struct device *dev; >> + struct dma_device common; >> + struct xilinx_vdma_chan *chan[XILINX_VDMA_MAX_CHANS_PER_DEVICE]; >> + bool has_sg; >> + u32 flush_on_fsync; >> +}; >> + >> +#define to_xilinx_chan(chan) \ >> + container_of(chan, struct xilinx_vdma_chan, common) >> + >> +/* IO accessors */ >> +static inline u32 vdma_read(struct xilinx_vdma_chan *chan, u32 reg) >> +{ >> + return ioread32(chan->xdev->regs + reg); >> +} >> + >> +static inline void vdma_write(struct xilinx_vdma_chan *chan, u32 reg, u32 value) >> +{ >> + iowrite32(value, chan->xdev->regs + reg); >> +} >> + >> +static inline void vdma_desc_write(struct xilinx_vdma_chan *chan, u32 reg, >> + u32 value) >> +{ >> + vdma_write(chan, chan->desc_offset + reg, value); >> +} >> + >> +static inline u32 vdma_ctrl_read(struct xilinx_vdma_chan *chan, u32 reg) >> +{ >> + return vdma_read(chan, chan->ctrl_offset + reg); >> +} >> + >> +static inline void vdma_ctrl_write(struct xilinx_vdma_chan *chan, u32 reg, >> + u32 value) >> +{ >> + vdma_write(chan, chan->ctrl_offset + reg, value); >> +} >> + >> +static inline void vdma_ctrl_clr(struct xilinx_vdma_chan *chan, u32 reg, >> + u32 clr) >> +{ >> + vdma_ctrl_write(chan, reg, vdma_ctrl_read(chan, reg) & ~clr); >> +} >> + >> +static inline void vdma_ctrl_set(struct xilinx_vdma_chan *chan, u32 reg, >> + u32 set) >> +{ >> + vdma_ctrl_write(chan, reg, vdma_ctrl_read(chan, reg) | set); >> +} >> + >> +/* ----------------------------------------------------------------------------- >> + * Descriptors and segments alloc and free >> + */ >> + >> +/** >> + * xilinx_vdma_alloc_tx_segment - Allocate transaction segment >> + * @chan: Driver specific VDMA channel >> + * >> + * Return: The allocated segment on success and NULL on failure. >> + */ >> +static struct xilinx_vdma_tx_segment * >> +xilinx_vdma_alloc_tx_segment(struct xilinx_vdma_chan *chan) >> +{ >> + struct xilinx_vdma_tx_segment *segment; >> + dma_addr_t phys; >> + >> + segment = dma_pool_alloc(chan->desc_pool, GFP_ATOMIC, &phys); >> + if (!segment) >> + return NULL; >> + >> + memset(segment, 0, sizeof(*segment)); >> + segment->phys = phys; >> + >> + return segment; >> +} >> + >> +/** >> + * xilinx_vdma_free_tx_segment - Free transaction segment >> + * @chan: Driver specific VDMA channel >> + * @segment: VDMA transaction segment >> + */ >> +static void xilinx_vdma_free_tx_segment(struct xilinx_vdma_chan *chan, >> + struct xilinx_vdma_tx_segment *segment) >> +{ >> + dma_pool_free(chan->desc_pool, segment, segment->phys); >> +} >> + >> +/** >> + * xilinx_vdma_tx_descriptor - Allocate transaction descriptor >> + * @chan: Driver specific VDMA channel >> + * >> + * Return: The allocated descriptor on success and NULL on failure. >> + */ >> +static struct xilinx_vdma_tx_descriptor * >> +xilinx_vdma_alloc_tx_descriptor(struct xilinx_vdma_chan *chan) >> +{ >> + struct xilinx_vdma_tx_descriptor *desc; >> + >> + desc = kzalloc(sizeof(*desc), GFP_KERNEL); >> + if (!desc) >> + return NULL; >> + >> + INIT_LIST_HEAD(&desc->segments); >> + >> + return desc; >> +} >> + >> +/** >> + * xilinx_vdma_free_tx_descriptor - Free transaction descriptor >> + * @chan: Driver specific VDMA channel >> + * @desc: VDMA transaction descriptor >> + */ >> +static void >> +xilinx_vdma_free_tx_descriptor(struct xilinx_vdma_chan *chan, >> + struct xilinx_vdma_tx_descriptor *desc) >> +{ >> + struct xilinx_vdma_tx_segment *segment, *next; >> + >> + if (!desc) >> + return; >> + >> + list_for_each_entry_safe(segment, next, &desc->segments, node) { >> + list_del(&segment->node); >> + xilinx_vdma_free_tx_segment(chan, segment); >> + } >> + >> + kfree(desc); >> +} >> + >> +/* Required functions */ >> + >> +/** >> + * xilinx_vdma_free_descriptors - Free descriptors list >> + * @chan: Driver specific VDMA channel >> + * @list: List to parse and delete the descriptor >> + */ >> +static void xilinx_vdma_free_desc_list(struct xilinx_vdma_chan *chan, >> + struct list_head *list) >> +{ >> + struct xilinx_vdma_tx_descriptor *desc, *next; >> + >> + list_for_each_entry_safe(desc, next, list, node) { >> + list_del(&desc->node); >> + xilinx_vdma_free_tx_descriptor(chan, desc); >> + } >> +} >> + >> +/** >> + * xilinx_vdma_free_descriptors - Free channel descriptors >> + * @chan: Driver specific VDMA channel >> + */ >> +static void xilinx_vdma_free_descriptors(struct xilinx_vdma_chan *chan) >> +{ >> + unsigned long flags; >> + >> + spin_lock_irqsave(&chan->lock, flags); >> + >> + xilinx_vdma_free_desc_list(chan, &chan->pending_list); >> + xilinx_vdma_free_desc_list(chan, &chan->done_list); >> + >> + xilinx_vdma_free_tx_descriptor(chan, chan->active_desc); >> + chan->active_desc = NULL; >> + >> + spin_unlock_irqrestore(&chan->lock, flags); >> +} >> + >> +/** >> + * xilinx_vdma_free_chan_resources - Free channel resources >> + * @dchan: DMA channel >> + */ >> +static void xilinx_vdma_free_chan_resources(struct dma_chan *dchan) >> +{ >> + struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan); >> + >> + dev_dbg(chan->dev, "Free all channel resources.\n"); >> + >> + tasklet_kill(&chan->tasklet); >> + xilinx_vdma_free_descriptors(chan); >> + dma_pool_destroy(chan->desc_pool); >> + chan->desc_pool = NULL; >> +} >> + >> +/** >> + * xilinx_vdma_chan_desc_cleanup - Clean channel descriptors >> + * @chan: Driver specific VDMA channel >> + */ >> +static void xilinx_vdma_chan_desc_cleanup(struct xilinx_vdma_chan *chan) >> +{ >> + struct xilinx_vdma_tx_descriptor *desc, *next; >> + unsigned long flags; >> + >> + spin_lock_irqsave(&chan->lock, flags); >> + >> + list_for_each_entry_safe(desc, next, &chan->done_list, node) { >> + dma_async_tx_callback callback; >> + void *callback_param; >> + >> + /* Remove from the list of running transactions */ >> + list_del(&desc->node); >> + >> + /* Run the link descriptor callback function */ >> + callback = desc->async_tx.callback; >> + callback_param = desc->async_tx.callback_param; >> + if (callback) { >> + spin_unlock_irqrestore(&chan->lock, flags); >> + callback(callback_param); >> + spin_lock_irqsave(&chan->lock, flags); >> + } >> + >> + /* Run any dependencies, then free the descriptor */ >> + dma_run_dependencies(&desc->async_tx); >> + xilinx_vdma_free_tx_descriptor(chan, desc); >> + } >> + >> + spin_unlock_irqrestore(&chan->lock, flags); >> +} >> + >> +/** >> + * xilinx_vdma_do_tasklet - Schedule completion tasklet >> + * @data: Pointer to the Xilinx VDMA channel structure >> + */ >> +static void xilinx_vdma_do_tasklet(unsigned long data) >> +{ >> + struct xilinx_vdma_chan *chan = (struct xilinx_vdma_chan *)data; >> + >> + xilinx_vdma_chan_desc_cleanup(chan); >> +} >> + >> +/** >> + * xilinx_vdma_alloc_chan_resources - Allocate channel resources >> + * @dchan: DMA channel >> + * >> + * Return: '1' on success and failure value on error > > May be return 0 on success as it usual practice? Here and in the other > places as well. Ok. > >> + */ >> +static int xilinx_vdma_alloc_chan_resources(struct dma_chan *dchan) >> +{ >> + struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan); >> + >> + /* Has this channel already been allocated? */ >> + if (chan->desc_pool) >> + return 1; >> + >> + /* >> + * We need the descriptor to be aligned to 64bytes >> + * for meeting Xilinx VDMA specification requirement. >> + */ >> + chan->desc_pool = dma_pool_create("xilinx_vdma_desc_pool", >> + chan->dev, >> + sizeof(struct xilinx_vdma_tx_segment), >> + __alignof__(struct xilinx_vdma_tx_segment), 0); >> + if (!chan->desc_pool) { >> + dev_err(chan->dev, >> + "unable to allocate channel %d descriptor pool\n", >> + chan->id); >> + return -ENOMEM; >> + } >> + >> + tasklet_init(&chan->tasklet, xilinx_vdma_do_tasklet, >> + (unsigned long)chan); >> + >> + chan->completed_cookie = DMA_MIN_COOKIE; >> + chan->cookie = DMA_MIN_COOKIE; >> + >> + /* There is at least one descriptor free to be allocated */ >> + return 1; >> +} >> + >> +/** >> + * xilinx_vdma_tx_status - Get VDMA transaction status >> + * @dchan: DMA channel >> + * @cookie: Transaction identifier >> + * @txstate: Transaction state >> + * >> + * Return: DMA transaction status >> + */ >> +static enum dma_status xilinx_vdma_tx_status(struct dma_chan *dchan, >> + dma_cookie_t cookie, >> + struct dma_tx_state *txstate) >> +{ >> + struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan); >> + dma_cookie_t last_used; >> + dma_cookie_t last_complete; >> + >> + xilinx_vdma_chan_desc_cleanup(chan); >> + >> + last_used = dchan->cookie; >> + last_complete = chan->completed_cookie; >> + >> + dma_set_tx_state(txstate, last_complete, last_used, 0); >> + >> + return dma_async_is_complete(cookie, last_complete, last_used); >> +} >> + >> +/** >> + * xilinx_vdma_is_running - Check if VDMA channel is running >> + * @chan: Driver specific VDMA channel >> + * >> + * Return: '1' if running, '0' if not. >> + */ >> +static int xilinx_vdma_is_running(struct xilinx_vdma_chan *chan) >> +{ >> + return !(vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) & >> + XILINX_VDMA_DMASR_HALTED) && >> + (vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) & >> + XILINX_VDMA_DMACR_RUNSTOP); >> +} >> + >> +/** >> + * xilinx_vdma_is_idle - Check if VDMA channel is idle >> + * @chan: Driver specific VDMA channel >> + * >> + * Return: '1' if idle, '0' if not. >> + */ >> +static int xilinx_vdma_is_idle(struct xilinx_vdma_chan *chan) >> +{ >> + return vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) & >> + XILINX_VDMA_DMASR_IDLE; >> +} >> + >> +/** >> + * xilinx_vdma_halt - Halt VDMA channel >> + * @chan: Driver specific VDMA channel >> + */ >> +static void xilinx_vdma_halt(struct xilinx_vdma_chan *chan) >> +{ >> + int loop = XILINX_VDMA_LOOP_COUNT + 1; >> + >> + vdma_ctrl_clr(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RUNSTOP); >> + >> + /* Wait for the hardware to halt */ >> + while (loop--) >> + if (vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) & >> + XILINX_VDMA_DMASR_HALTED) >> + break; >> + >> + if (!loop) { >> + dev_err(chan->dev, "Cannot stop channel %p: %x\n", >> + chan, vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR)); >> + chan->err = true; >> + } >> + >> + return; >> +} >> + >> +/** >> + * xilinx_vdma_start - Start VDMA channel >> + * @chan: Driver specific VDMA channel >> + */ >> +static void xilinx_vdma_start(struct xilinx_vdma_chan *chan) >> +{ >> + int loop = XILINX_VDMA_LOOP_COUNT + 1; >> + >> + vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RUNSTOP); >> + >> + /* Wait for the hardware to start */ >> + while (loop--) >> + if (!(vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR) & >> + XILINX_VDMA_DMASR_HALTED)) >> + break; >> + >> + if (!loop) { >> + dev_err(chan->dev, "Cannot start channel %p: %x\n", >> + chan, vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR)); >> + >> + chan->err = true; >> + } >> + >> + return; >> +} >> + >> +/** >> + * xilinx_vdma_start_transfer - Starts VDMA transfer >> + * @chan: Driver specific channel struct pointer >> + */ >> +static void xilinx_vdma_start_transfer(struct xilinx_vdma_chan *chan) >> +{ >> + struct xilinx_vdma_config *config = &chan->config; >> + struct xilinx_vdma_tx_descriptor *desc; >> + unsigned long flags; >> + u32 reg; >> + struct xilinx_vdma_tx_segment *head, *tail = NULL; >> + >> + if (chan->err) >> + return; >> + >> + spin_lock_irqsave(&chan->lock, flags); >> + >> + /* There's already an active descriptor, bail out. */ >> + if (chan->active_desc) >> + goto out_unlock; >> + >> + if (list_empty(&chan->pending_list)) >> + goto out_unlock; >> + >> + desc = list_first_entry(&chan->pending_list, >> + struct xilinx_vdma_tx_descriptor, node); >> + >> + /* If it is SG mode and hardware is busy, cannot submit */ >> + if (chan->has_sg && xilinx_vdma_is_running(chan) && >> + !xilinx_vdma_is_idle(chan)) { >> + dev_dbg(chan->dev, "DMA controller still busy\n"); >> + goto out_unlock; >> + } >> + >> + if (chan->err) >> + goto out_unlock; >> + >> + /* >> + * If hardware is idle, then all descriptors on the running lists are >> + * done, start new transfers >> + */ >> + if (chan->has_sg) { >> + head = list_first_entry(&desc->segments, >> + struct xilinx_vdma_tx_segment, node); >> + tail = list_entry(desc->segments.prev, >> + struct xilinx_vdma_tx_segment, node); >> + >> + vdma_ctrl_write(chan, XILINX_VDMA_REG_CURDESC, head->phys); >> + } >> + >> + /* Configure the hardware using info in the config structure */ >> + reg = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR); >> + >> + if (config->frm_cnt_en) >> + reg |= XILINX_VDMA_DMACR_FRAMECNT_EN; >> + else >> + reg &= ~XILINX_VDMA_DMACR_FRAMECNT_EN; >> + >> + /* >> + * With SG, start with circular mode, so that BDs can be fetched. >> + * In direct register mode, if not parking, enable circular mode >> + */ >> + if (chan->has_sg || !config->park) >> + reg |= XILINX_VDMA_DMACR_CIRC_EN; >> + >> + if (config->park) >> + reg &= ~XILINX_VDMA_DMACR_CIRC_EN; >> + >> + vdma_ctrl_write(chan, XILINX_VDMA_REG_DMACR, reg); >> + >> + if (config->park && (config->park_frm >= 0) && >> + (config->park_frm < chan->num_frms)) { >> + if (chan->direction == DMA_MEM_TO_DEV) >> + vdma_write(chan, XILINX_VDMA_REG_PARK_PTR, >> + config->park_frm << >> + XILINX_VDMA_PARK_PTR_RD_REF_SHIFT); >> + else >> + vdma_write(chan, XILINX_VDMA_REG_PARK_PTR, >> + config->park_frm << >> + XILINX_VDMA_PARK_PTR_WR_REF_SHIFT); >> + } >> + >> + /* Start the hardware */ >> + xilinx_vdma_start(chan); >> + >> + if (chan->err) >> + goto out_unlock; >> + >> + /* Start the transfer */ >> + if (chan->has_sg) { >> + vdma_ctrl_write(chan, XILINX_VDMA_REG_TAILDESC, tail->phys); >> + } else { >> + struct xilinx_vdma_tx_segment *segment; >> + int i = 0; >> + >> + list_for_each_entry(segment, &desc->segments, node) >> + vdma_desc_write(chan, >> + XILINX_VDMA_REG_START_ADDRESS(i++), >> + segment->hw.buf_addr); >> + >> + vdma_desc_write(chan, XILINX_VDMA_REG_HSIZE, config->hsize); >> + vdma_desc_write(chan, XILINX_VDMA_REG_FRMDLY_STRIDE, >> + (config->frm_dly << >> + XILINX_VDMA_FRMDLY_STRIDE_FRMDLY_SHIFT) | >> + (config->stride << >> + XILINX_VDMA_FRMDLY_STRIDE_STRIDE_SHIFT)); >> + vdma_desc_write(chan, XILINX_VDMA_REG_VSIZE, config->vsize); >> + } >> + >> + list_del(&desc->node); >> + chan->active_desc = desc; >> + >> +out_unlock: >> + spin_unlock_irqrestore(&chan->lock, flags); >> +} >> + >> +/** >> + * xilinx_vdma_issue_pending - Issue pending transactions >> + * @dchan: DMA channel >> + */ >> +static void xilinx_vdma_issue_pending(struct dma_chan *dchan) >> +{ >> + struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan); >> + >> + xilinx_vdma_start_transfer(chan); >> +} >> + >> +/** >> + * xilinx_vdma_complete_descriptor - Mark the active descriptor as complete >> + * @chan : xilinx DMA channel >> + * >> + * CONTEXT: hardirq >> + */ >> +static void xilinx_vdma_complete_descriptor(struct xilinx_vdma_chan *chan) >> +{ >> + struct xilinx_vdma_tx_descriptor *desc; >> + unsigned long flags; >> + >> + spin_lock_irqsave(&chan->lock, flags); >> + >> + desc = chan->active_desc; >> + if (!desc) { >> + dev_dbg(chan->dev, "no running descriptors\n"); >> + goto out_unlock; >> + } >> + >> + list_add_tail(&desc->node, &chan->done_list); >> + >> + /* Update the completed cookie and reset the active descriptor. */ >> + chan->completed_cookie = desc->async_tx.cookie; >> + chan->active_desc = NULL; >> + >> +out_unlock: >> + spin_unlock_irqrestore(&chan->lock, flags); >> +} >> + >> +/** >> + * xilinx_vdma_reset - Reset VDMA channel >> + * @chan: Driver specific VDMA channel >> + * >> + * Return: '0' on success and failure value on error >> + */ >> +static int xilinx_vdma_reset(struct xilinx_vdma_chan *chan) >> +{ >> + int loop = XILINX_VDMA_LOOP_COUNT + 1; >> + u32 tmp; >> + >> + vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR, XILINX_VDMA_DMACR_RESET); >> + >> + tmp = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) & >> + XILINX_VDMA_DMACR_RESET; >> + >> + /* Wait for the hardware to finish reset */ >> + while (loop-- && tmp) >> + tmp = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR) & >> + XILINX_VDMA_DMACR_RESET; >> + >> + if (!loop) { >> + dev_err(chan->dev, "reset timeout, cr %x, sr %x\n", >> + vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR), >> + vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR)); >> + return -ETIMEDOUT; >> + } >> + >> + chan->err = false; >> + >> + return 0; >> +} >> + >> +/** >> + * xilinx_vdma_chan_reset - Reset VDMA channel and enable interrupts >> + * @chan: Driver specific VDMA channel >> + * >> + * Return: '0' on success and failure value on error >> + */ >> +static int xilinx_vdma_chan_reset(struct xilinx_vdma_chan *chan) >> +{ >> + int err; >> + >> + /* Reset VDMA */ >> + err = xilinx_vdma_reset(chan); >> + if (err) >> + return err; >> + >> + /* Enable interrupts */ >> + vdma_ctrl_set(chan, XILINX_VDMA_REG_DMACR, >> + XILINX_VDMA_DMAXR_ALL_IRQ_MASK); >> + >> + return 0; >> +} >> + >> +/** >> + * xilinx_vdma_irq_handler - VDMA Interrupt handler >> + * @irq: IRQ number >> + * @data: Pointer to the Xilinx VDMA channel structure >> + * >> + * Return: IRQ_HANDLED/IRQ_NONE >> + */ >> +static irqreturn_t xilinx_vdma_irq_handler(int irq, void *data) >> +{ >> + struct xilinx_vdma_chan *chan = data; >> + u32 status; >> + >> + /* Read the status and ack the interrupts. */ >> + status = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMASR); >> + if (!(status & XILINX_VDMA_DMAXR_ALL_IRQ_MASK)) >> + return IRQ_NONE; >> + >> + vdma_ctrl_write(chan, XILINX_VDMA_REG_DMASR, >> + status & XILINX_VDMA_DMAXR_ALL_IRQ_MASK); >> + >> + if (status & XILINX_VDMA_DMASR_ERR_IRQ) { >> + /* >> + * An error occurred. If C_FLUSH_ON_FSYNC is enabled and the >> + * error is recoverable, ignore it. Otherwise flag the error. >> + * >> + * Only recoverable errors can be cleared in the DMASR register, >> + * make sure not to write to other error bits to 1. >> + */ >> + u32 errors = status & XILINX_VDMA_DMASR_ALL_ERR_MASK; >> + vdma_ctrl_write(chan, XILINX_VDMA_REG_DMASR, >> + errors & XILINX_VDMA_DMASR_ERR_RECOVER_MASK); >> + >> + if (!chan->flush_on_fsync || >> + (errors & ~XILINX_VDMA_DMASR_ERR_RECOVER_MASK)) { >> + dev_err(chan->dev, >> + "Channel %p has errors %x, cdr %x tdr %x\n", >> + chan, errors, >> + vdma_ctrl_read(chan, XILINX_VDMA_REG_CURDESC), >> + vdma_ctrl_read(chan, XILINX_VDMA_REG_TAILDESC)); >> + chan->err = true; >> + } >> + } >> + >> + if (status & XILINX_VDMA_DMASR_DLY_CNT_IRQ) { >> + /* >> + * Device takes too long to do the transfer when user requires >> + * responsiveness. >> + */ >> + dev_dbg(chan->dev, "Inter-packet latency too long\n"); >> + } >> + >> + if (status & XILINX_VDMA_DMASR_FRM_CNT_IRQ) { >> + xilinx_vdma_complete_descriptor(chan); >> + xilinx_vdma_start_transfer(chan); >> + } >> + >> + tasklet_schedule(&chan->tasklet); >> + return IRQ_HANDLED; >> +} >> + >> +/** >> + * xilinx_vdma_tx_submit - Submit DMA transaction >> + * @tx: Async transaction descriptor >> + * >> + * Return: cookie value on success and failure value on error >> + */ >> +static dma_cookie_t xilinx_vdma_tx_submit(struct dma_async_tx_descriptor *tx) >> +{ >> + struct xilinx_vdma_tx_descriptor *desc = to_vdma_tx_descriptor(tx); >> + struct xilinx_vdma_chan *chan = to_xilinx_chan(tx->chan); >> + struct xilinx_vdma_tx_segment *segment; >> + dma_cookie_t cookie; >> + unsigned long flags; >> + int err; >> + >> + if (chan->err) { >> + /* >> + * If reset fails, need to hard reset the system. >> + * Channel is no longer functional >> + */ >> + err = xilinx_vdma_chan_reset(chan); >> + if (err < 0) >> + return err; >> + } >> + >> + spin_lock_irqsave(&chan->lock, flags); >> + >> + /* Assign cookies to all of the segments that make up this transaction. >> + * Use the cookie of the last segment as the transaction cookie. >> + */ > > Keep style of multiline comment the same over the code. Sure. > >> + cookie = chan->cookie; >> + >> + list_for_each_entry(segment, &desc->segments, node) { >> + if (cookie < DMA_MAX_COOKIE) >> + cookie++; >> + else >> + cookie = DMA_MIN_COOKIE; >> + >> + segment->cookie = cookie; >> + } >> + >> + tx->cookie = cookie; >> + chan->cookie = cookie; >> + >> + /* Append the transaction to the pending transactions queue. */ >> + list_add_tail(&desc->node, &chan->pending_list); >> + >> + spin_unlock_irqrestore(&chan->lock, flags); >> + >> + return cookie; >> +} >> + >> +/** >> + * xilinx_vdma_prep_slave_sg - prepare a descriptor for a DMA_SLAVE transaction >> + * @dchan: DMA channel >> + * @sgl: scatterlist to transfer to/from >> + * @sg_len: number of entries in @sgl >> + * @dir: DMA direction >> + * @flags: transfer ack flags >> + * @context: unused >> + * >> + * Return: Async transaction descriptor on success and NULL on failure >> + */ >> +static struct dma_async_tx_descriptor * >> +xilinx_vdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl, >> + unsigned int sg_len, enum dma_transfer_direction dir, >> + unsigned long flags, void *context) >> +{ >> + struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan); >> + struct xilinx_vdma_tx_descriptor *desc; >> + struct xilinx_vdma_tx_segment *segment; >> + struct xilinx_vdma_tx_segment *prev = NULL; >> + struct scatterlist *sg; >> + int i; >> + >> + if (chan->direction != dir || sg_len == 0) >> + return NULL; >> + >> + /* Enforce one sg entry for one frame. */ >> + if (sg_len != chan->num_frms) { >> + dev_err(chan->dev, >> + "number of entries %d not the same as num stores %d\n", >> + sg_len, chan->num_frms); >> + return NULL; >> + } >> + >> + /* Allocate a transaction descriptor. */ >> + desc = xilinx_vdma_alloc_tx_descriptor(chan); >> + if (!desc) >> + return NULL; >> + >> + dma_async_tx_descriptor_init(&desc->async_tx, &chan->common); >> + desc->async_tx.tx_submit = xilinx_vdma_tx_submit; >> + desc->async_tx.cookie = 0; >> + async_tx_ack(&desc->async_tx); >> + >> + /* Build the list of transaction segments. */ >> + for_each_sg(sgl, sg, sg_len, i) { >> + struct xilinx_vdma_desc_hw *hw; >> + >> + /* Allocate the link descriptor from DMA pool */ >> + segment = xilinx_vdma_alloc_tx_segment(chan); >> + if (!segment) >> + goto error; >> + >> + /* Fill in the hardware descriptor */ >> + hw = &segment->hw; >> + hw->buf_addr = sg_dma_address(sg); >> + hw->vsize = chan->config.vsize; >> + hw->hsize = chan->config.hsize; >> + hw->stride = (chan->config.frm_dly << >> + XILINX_VDMA_FRMDLY_STRIDE_FRMDLY_SHIFT) | >> + (chan->config.stride << >> + XILINX_VDMA_FRMDLY_STRIDE_STRIDE_SHIFT); >> + if (prev) >> + prev->hw.next_desc = segment->phys; >> + >> + /* Insert the segment into the descriptor segments list. */ >> + list_add_tail(&segment->node, &desc->segments); >> + >> + prev = segment; >> + } >> + >> + /* Link the last hardware descriptor with the first. */ >> + segment = list_first_entry(&desc->segments, >> + struct xilinx_vdma_tx_segment, node); >> + prev->hw.next_desc = segment->phys; >> + >> + return &desc->async_tx; >> + >> +error: >> + xilinx_vdma_free_tx_descriptor(chan, desc); >> + return NULL; >> +} >> + >> +/** >> + * xilinx_vdma_terminate_all - Halt the channel and free descriptors >> + * @chan: Driver specific VDMA Channel pointer >> + */ >> +static void xilinx_vdma_terminate_all(struct xilinx_vdma_chan *chan) >> +{ >> + /* Halt the DMA engine */ >> + xilinx_vdma_halt(chan); >> + >> + /* Remove and free all of the descriptors in the lists */ >> + xilinx_vdma_free_descriptors(chan); >> +} >> + >> +/** >> + * xilinx_vdma_slave_config - Configure VDMA channel >> + * Run-time configuration for Axi VDMA, supports: >> + * . halt the channel >> + * . configure interrupt coalescing and inter-packet delay threshold >> + * . start/stop parking >> + * . enable genlock >> + * . set transfer information using config struct >> + * >> + * @chan: Driver specific VDMA Channel pointer >> + * @cfg: Channel configuration pointer >> + * >> + * Return: '0' on success and failure value on error >> + */ >> +static int xilinx_vdma_slave_config(struct xilinx_vdma_chan *chan, >> + struct xilinx_vdma_config *cfg) >> +{ >> + u32 dmacr; >> + >> + if (cfg->reset) >> + return xilinx_vdma_chan_reset(chan); >> + >> + dmacr = vdma_ctrl_read(chan, XILINX_VDMA_REG_DMACR); >> + >> + /* If vsize is -1, it is park-related operations */ >> + if (cfg->vsize == -1) { >> + if (cfg->park) >> + dmacr &= ~XILINX_VDMA_DMACR_CIRC_EN; >> + else >> + dmacr |= XILINX_VDMA_DMACR_CIRC_EN; >> + >> + vdma_ctrl_write(chan, XILINX_VDMA_REG_DMACR, dmacr); >> + return 0; >> + } >> + >> + /* If hsize is -1, it is interrupt threshold settings */ >> + if (cfg->hsize == -1) { >> + if (cfg->coalesc <= XILINX_VDMA_DMACR_FRAME_COUNT_MAX) { >> + dmacr &= ~XILINX_VDMA_DMACR_FRAME_COUNT_MASK; >> + dmacr |= cfg->coalesc << >> + XILINX_VDMA_DMACR_FRAME_COUNT_SHIFT; >> + chan->config.coalesc = cfg->coalesc; >> + } >> + >> + if (cfg->delay <= XILINX_VDMA_DMACR_DELAY_MAX) { >> + dmacr &= ~XILINX_VDMA_DMACR_DELAY_MASK; >> + dmacr |= cfg->delay << XILINX_VDMA_DMACR_DELAY_SHIFT; >> + chan->config.delay = cfg->delay; >> + } >> + >> + vdma_ctrl_write(chan, XILINX_VDMA_REG_DMACR, dmacr); >> + return 0; >> + } >> + >> + /* Transfer information */ >> + chan->config.vsize = cfg->vsize; >> + chan->config.hsize = cfg->hsize; >> + chan->config.stride = cfg->stride; >> + chan->config.frm_dly = cfg->frm_dly; >> + chan->config.park = cfg->park; >> + >> + /* genlock settings */ >> + chan->config.gen_lock = cfg->gen_lock; >> + chan->config.master = cfg->master; >> + >> + if (cfg->gen_lock && chan->genlock) { >> + dmacr |= XILINX_VDMA_DMACR_GENLOCK_EN; >> + dmacr |= cfg->master << XILINX_VDMA_DMACR_MASTER_SHIFT; >> + } >> + >> + chan->config.frm_cnt_en = cfg->frm_cnt_en; >> + if (cfg->park) >> + chan->config.park_frm = cfg->park_frm; >> + else >> + chan->config.park_frm = -1; >> + >> + chan->config.coalesc = cfg->coalesc; >> + chan->config.delay = cfg->delay; >> + if (cfg->coalesc <= XILINX_VDMA_DMACR_FRAME_COUNT_MAX) { >> + dmacr |= cfg->coalesc << XILINX_VDMA_DMACR_FRAME_COUNT_SHIFT; >> + chan->config.coalesc = cfg->coalesc; >> + } >> + >> + if (cfg->delay <= XILINX_VDMA_DMACR_DELAY_MAX) { >> + dmacr |= cfg->delay << XILINX_VDMA_DMACR_DELAY_SHIFT; >> + chan->config.delay = cfg->delay; >> + } >> + >> + /* FSync Source selection */ >> + dmacr &= ~XILINX_VDMA_DMACR_FSYNCSRC_MASK; >> + dmacr |= cfg->ext_fsync << XILINX_VDMA_DMACR_FSYNCSRC_SHIFT; >> + >> + vdma_ctrl_write(chan, XILINX_VDMA_REG_DMACR, dmacr); >> + return 0; >> +} >> + >> +/** >> + * xilinx_vdma_device_control - Configure DMA channel of the device >> + * @dchan: DMA Channel pointer >> + * @cmd: DMA control command >> + * @arg: Channel configuration >> + * >> + * Return: '0' on success and failure value on error >> + */ >> +static int xilinx_vdma_device_control(struct dma_chan *dchan, >> + enum dma_ctrl_cmd cmd, unsigned long arg) >> +{ >> + struct xilinx_vdma_chan *chan = to_xilinx_chan(dchan); >> + >> + switch (cmd) { >> + case DMA_TERMINATE_ALL: >> + xilinx_vdma_terminate_all(chan); >> + return 0; >> + case DMA_SLAVE_CONFIG: >> + return xilinx_vdma_slave_config(chan, >> + (struct xilinx_vdma_config *)arg); >> + default: >> + return -ENXIO; >> + } >> +} >> + >> +/* ----------------------------------------------------------------------------- >> + * Probe and remove >> + */ >> + >> +/** >> + * xilinx_vdma_chan_remove - Per Channel remove function >> + * @chan: Driver specific VDMA channel >> + */ >> +static void xilinx_vdma_chan_remove(struct xilinx_vdma_chan *chan) >> +{ >> + /* Disable all interrupts */ >> + vdma_ctrl_clr(chan, XILINX_VDMA_REG_DMACR, >> + XILINX_VDMA_DMAXR_ALL_IRQ_MASK); >> + >> + list_del(&chan->common.device_node); >> +} >> + >> +/** >> + * xilinx_vdma_chan_probe - Per Channel Probing >> + * It get channel features from the device tree entry and >> + * initialize special channel handling routines >> + * >> + * @xdev: Driver specific device structure >> + * @node: Device node >> + * >> + * Return: '0' on success and failure value on error >> + */ >> +static int xilinx_vdma_chan_probe(struct xilinx_vdma_device *xdev, >> + struct device_node *node) >> +{ >> + struct xilinx_vdma_chan *chan; >> + bool has_dre = false; >> + u32 value; >> + int err; >> + >> + /* Allocate and initialize the channel structure */ >> + chan = devm_kzalloc(xdev->dev, sizeof(*chan), GFP_KERNEL); >> + if (!chan) >> + return -ENOMEM; >> + >> + chan->dev = xdev->dev; >> + chan->xdev = xdev; >> + chan->has_sg = xdev->has_sg; >> + >> + spin_lock_init(&chan->lock); >> + INIT_LIST_HEAD(&chan->pending_list); >> + INIT_LIST_HEAD(&chan->done_list); >> + >> + /* Retrieve the channel properties from the device tree */ >> + has_dre = of_property_read_bool(node, "xlnx,include-dre"); >> + >> + chan->genlock = of_property_read_bool(node, "xlnx,genlock-mode"); >> + >> + err = of_property_read_u32(node, "xlnx,datawidth", &value); >> + if (!err) { >> + u32 width = value >> 3; /* Convert bits to bytes */ >> + >> + /* If data width is greater than 8 bytes, DRE is not in hw */ >> + if (width > 8) >> + has_dre = false; >> + >> + if (!has_dre) >> + xdev->common.copy_align = fls(width - 1); >> + } else { >> + dev_err(xdev->dev, "missing xlnx,datawidth property\n"); >> + return err; >> + } >> + >> + if (of_device_is_compatible(node, "xlnx,axi-vdma-mm2s-channel")) { >> + chan->direction = DMA_MEM_TO_DEV; >> + chan->id = 0; >> + >> + chan->ctrl_offset = XILINX_VDMA_MM2S_CTRL_OFFSET; >> + chan->desc_offset = XILINX_VDMA_MM2S_DESC_OFFSET; >> + >> + if (xdev->flush_on_fsync == XILINX_VDMA_FLUSH_BOTH || >> + xdev->flush_on_fsync == XILINX_VDMA_FLUSH_MM2S) >> + chan->flush_on_fsync = true; >> + } else if (of_device_is_compatible(node, >> + "xlnx,axi-vdma-s2mm-channel")) { >> + chan->direction = DMA_DEV_TO_MEM; >> + chan->id = 1; >> + >> + chan->ctrl_offset = XILINX_VDMA_S2MM_CTRL_OFFSET; >> + chan->desc_offset = XILINX_VDMA_S2MM_DESC_OFFSET; >> + >> + if (xdev->flush_on_fsync == XILINX_VDMA_FLUSH_BOTH || >> + xdev->flush_on_fsync == XILINX_VDMA_FLUSH_S2MM) >> + chan->flush_on_fsync = true; >> + } else { >> + dev_err(xdev->dev, "Invalid channel compatible node\n"); >> + return -EINVAL; >> + } >> + >> + /* Request the interrupt */ >> + chan->irq = irq_of_parse_and_map(node, 0); >> + err = devm_request_irq(xdev->dev, chan->irq, xilinx_vdma_irq_handler, >> + IRQF_SHARED, "xilinx-vdma-controller", chan); >> + if (err) { >> + dev_err(xdev->dev, "unable to request IRQ\n"); >> + return err; >> + } >> + >> + /* Initialize the DMA channel and add it to the DMA engine channels >> + * list. >> + */ >> + chan->common.device = &xdev->common; >> + >> + list_add_tail(&chan->common.device_node, &xdev->common.channels); >> + xdev->chan[chan->id] = chan; >> + >> + /* Reset the channel */ >> + err = xilinx_vdma_chan_reset(chan); >> + if (err < 0) { >> + dev_err(xdev->dev, "Reset channel failed\n"); >> + return err; >> + } >> + >> + return 0; >> +} >> + >> +/** >> + * struct of_dma_filter_xilinx_args - Channel filter args >> + * @dev: DMA device structure >> + * @chan_id: Channel id >> + */ >> +struct of_dma_filter_xilinx_args { >> + struct dma_device *dev; >> + u32 chan_id; >> +}; >> + >> +/** >> + * xilinx_vdma_dt_filter - VDMA channel filter function >> + * @chan: DMA channel pointer >> + * @param: Filter match value >> + * >> + * Return: true/false based on the result >> + */ >> +static bool xilinx_vdma_dt_filter(struct dma_chan *chan, void *param) >> +{ >> + struct of_dma_filter_xilinx_args *args = param; >> + >> + return chan->device == args->dev && chan->chan_id == args->chan_id; >> +} >> + >> +/** >> + * of_dma_xilinx_xlate - Translation function >> + * @dma_spec: Pointer to DMA specifier as found in the device tree >> + * @ofdma: Pointer to DMA controller data >> + * >> + * Return: DMA channel pointer on success and NULL on error >> + */ >> +static struct dma_chan *of_dma_xilinx_xlate(struct of_phandle_args *dma_spec, >> + struct of_dma *ofdma) >> +{ >> + struct of_dma_filter_xilinx_args args; >> + dma_cap_mask_t cap; >> + >> + args.dev = ofdma->of_dma_data; >> + if (!args.dev) >> + return NULL; >> + >> + if (dma_spec->args_count != 1) >> + return NULL; >> + >> + dma_cap_zero(cap); >> + dma_cap_set(DMA_SLAVE, cap); >> + >> + args.chan_id = dma_spec->args[0]; >> + >> + return dma_request_channel(cap, xilinx_vdma_dt_filter, &args); >> +} >> + >> +/** >> + * xilinx_vdma_probe - Driver probe function >> + * @pdev: Pointer to the platform_device structure >> + * >> + * Return: '0' on success and failure value on error >> + */ >> +static int xilinx_vdma_probe(struct platform_device *pdev) >> +{ >> + struct device_node *node = pdev->dev.of_node; >> + struct xilinx_vdma_device *xdev; >> + struct device_node *child; >> + struct resource *io; >> + u32 num_frames; >> + int i, err; >> + >> + dev_info(&pdev->dev, "Probing xilinx axi vdma engine\n"); >> + >> + /* Allocate and initialize the DMA engine structure */ >> + xdev = devm_kzalloc(&pdev->dev, sizeof(*xdev), GFP_KERNEL); >> + if (!xdev) >> + return -ENOMEM; >> + >> + xdev->dev = &pdev->dev; >> + >> + /* Request and map I/O memory */ >> + io = platform_get_resource(pdev, IORESOURCE_MEM, 0); >> + xdev->regs = devm_ioremap_resource(&pdev->dev, io); >> + if (IS_ERR(xdev->regs)) >> + return PTR_ERR(xdev->regs); >> + >> + /* Retrieve the DMA engine properties from the device tree */ >> + xdev->has_sg = of_property_read_bool(node, "xlnx,include-sg"); >> + >> + err = of_property_read_u32(node, "xlnx,num-fstores", &num_frames); >> + if (err < 0) { >> + dev_err(xdev->dev, "missing xlnx,num-fstores property\n"); >> + return err; >> + } >> + >> + of_property_read_u32(node, "xlnx,flush-fsync", &xdev->flush_on_fsync); >> + >> + /* Initialize the DMA engine */ >> + xdev->common.dev = &pdev->dev; >> + >> + INIT_LIST_HEAD(&xdev->common.channels); >> + dma_cap_set(DMA_SLAVE, xdev->common.cap_mask); >> + dma_cap_set(DMA_PRIVATE, xdev->common.cap_mask); >> + >> + xdev->common.device_alloc_chan_resources = >> + xilinx_vdma_alloc_chan_resources; >> + xdev->common.device_free_chan_resources = >> + xilinx_vdma_free_chan_resources; >> + xdev->common.device_prep_slave_sg = xilinx_vdma_prep_slave_sg; >> + xdev->common.device_control = xilinx_vdma_device_control; >> + xdev->common.device_tx_status = xilinx_vdma_tx_status; >> + xdev->common.device_issue_pending = xilinx_vdma_issue_pending; >> + >> + platform_set_drvdata(pdev, xdev); >> + >> + /* Initialize the channels */ >> + for_each_child_of_node(node, child) { >> + err = xilinx_vdma_chan_probe(xdev, child); >> + if (err < 0) >> + goto error; >> + } >> + >> + for (i = 0; i < XILINX_VDMA_MAX_CHANS_PER_DEVICE; i++) { >> + if (xdev->chan[i]) >> + xdev->chan[i]->num_frms = num_frames; >> + } >> + >> + /* Register the DMA engine with the core */ >> + dma_async_device_register(&xdev->common); >> + >> + err = of_dma_controller_register(node, of_dma_xilinx_xlate, >> + &xdev->common); >> + if (err < 0) { >> + dev_err(&pdev->dev, "Unable to register DMA to DT\n"); >> + dma_async_device_unregister(&xdev->common); >> + goto error; >> + } >> + >> + return 0; >> + >> +error: >> + for (i = 0; i < XILINX_VDMA_MAX_CHANS_PER_DEVICE; i++) { >> + if (xdev->chan[i]) >> + xilinx_vdma_chan_remove(xdev->chan[i]); >> + } >> + >> + return err; >> +} >> + >> +/** >> + * xilinx_vdma_remove - Driver remove function >> + * @pdev: Pointer to the platform_device structure >> + * >> + * Return: Always '0' >> + */ >> +static int xilinx_vdma_remove(struct platform_device *pdev) >> +{ >> + struct xilinx_vdma_device *xdev; >> + int i; >> + >> + of_dma_controller_free(pdev->dev.of_node); >> + >> + xdev = platform_get_drvdata(pdev); > > You could move this assignment to a variables block, it's normal > practice. Ok. I will send v3 fixing the comments. Srikanth > >> + dma_async_device_unregister(&xdev->common); >> + >> + for (i = 0; i < XILINX_VDMA_MAX_CHANS_PER_DEVICE; i++) { >> + if (xdev->chan[i]) >> + xilinx_vdma_chan_remove(xdev->chan[i]); >> + } >> + >> + return 0; >> +} >> + >> +static const struct of_device_id xilinx_vdma_of_ids[] = { >> + { .compatible = "xlnx,axi-vdma-1.00.a",}, >> + {} >> +}; >> + >> +static struct platform_driver xilinx_vdma_driver = { >> + .driver = { >> + .name = "xilinx-vdma", >> + .owner = THIS_MODULE, >> + .of_match_table = xilinx_vdma_of_ids, >> + }, >> + .probe = xilinx_vdma_probe, >> + .remove = xilinx_vdma_remove, >> +}; >> + >> +module_platform_driver(xilinx_vdma_driver); >> + >> +MODULE_AUTHOR("Xilinx, Inc."); >> +MODULE_DESCRIPTION("Xilinx VDMA driver"); >> +MODULE_LICENSE("GPL v2"); >> diff --git a/include/linux/amba/xilinx_dma.h b/include/linux/amba/xilinx_dma.h >> new file mode 100644 >> index 0000000..48a8c8b >> --- /dev/null >> +++ b/include/linux/amba/xilinx_dma.h >> @@ -0,0 +1,50 @@ >> +/* >> + * Xilinx DMA Engine drivers support header file >> + * >> + * Copyright (C) 2010-2014 Xilinx, Inc. All rights reserved. >> + * >> + * This is free software; you can redistribute it and/or modify >> + * it under the terms of the GNU General Public License as published by >> + * the Free Software Foundation; either version 2 of the License, or >> + * (at your option) any later version. >> + */ >> + >> +#ifndef __DMA_XILINX_DMA_H >> +#define __DMA_XILINX_DMA_H >> + >> +#include >> +#include >> + >> +/** >> + * struct xilinx_vdma_config - VDMA Configuration structure >> + * @vsize: Vertical size >> + * @hsize: Horizontal size >> + * @stride: Stride >> + * @frm_dly: Frame delay >> + * @gen_lock: Whether in gen-lock mode >> + * @master: Master that it syncs to >> + * @frm_cnt_en: Enable frame count enable >> + * @park: Whether wants to park >> + * @park_frm: Frame to park on >> + * @coalesc: Interrupt coalescing threshold >> + * @delay: Delay counter >> + * @reset: Reset Channel >> + * @ext_fsync: External Frame Sync source >> + */ >> +struct xilinx_vdma_config { >> + int vsize; >> + int hsize; >> + int stride; >> + int frm_dly; >> + int gen_lock; >> + int master; >> + int frm_cnt_en; >> + int park; >> + int park_frm; >> + int coalesc; >> + int delay; >> + int reset; >> + int ext_fsync; >> +}; >> + >> +#endif > > -- > Andy Shevchenko > Intel Finland Oy > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/