[PATCHv8 2/2] dma: Add Freescale eDMA engine driver support
Jingchang Lu
jingchang.lu at freescale.com
Wed Jan 8 05:24:38 EST 2014
Hi, Vinod, Mark and other maintainers,
Could you please help review this Freescale eDMA driver and the dts binding.
Many thanks!
Best Regards,
Jingchang
> -----Original Message-----
> From: Jingchang Lu [mailto:b35083 at freescale.com]
> Sent: Thursday, January 02, 2014 2:52 PM
> To: vinod.koul at intel.com
> Cc: dan.j.williams at intel.com; shawn.guo at linaro.org; pawel.moll at arm.com;
> mark.rutland at arm.com; swarren at wwwdotorg.org; linux-kernel at vger.kernel.org;
> linux-arm-kernel at lists.infradead.org; devicetree at vger.kernel.org; Lu
> Jingchang-B35083; Wang Huan-B18965
> Subject: [PATCHv8 2/2] dma: Add Freescale eDMA engine driver support
>
> Add Freescale enhanced direct memory(eDMA) controller support.
> This module can be found on Vybrid and LS-1 SoCs.
>
> Signed-off-by: Alison Wang <b18965 at freescale.com>
> Signed-off-by: Jingchang Lu <b35083 at freescale.com>
> ---
> changes in v8:
> change the edma driver according eDMA dts change.
> add big-endian and little-endian handling.
>
> no changes in v4 ~ v7.
>
> changes in v3:
> add vf610 edma dt-bindings namespace with prefix VF610_*.
>
> changes in v2:
> using generic dma-channels property instead of fsl,dma-channels.
>
> Documentation/devicetree/bindings/dma/fsl-edma.txt | 67 ++
> drivers/dma/Kconfig | 10 +
> drivers/dma/Makefile | 1 +
> drivers/dma/fsl-edma.c | 939
> +++++++++++++++++++++
> 4 files changed, 1017 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/dma/fsl-edma.txt
> create mode 100644 drivers/dma/fsl-edma.c
>
> diff --git a/Documentation/devicetree/bindings/dma/fsl-edma.txt
> b/Documentation/devicetree/bindings/dma/fsl-edma.txt
> new file mode 100644
> index 0000000..3ff6603
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/dma/fsl-edma.txt
> @@ -0,0 +1,67 @@
> +* Freescale enhanced Direct Memory Access(eDMA) Controller
> +
> + The eDMA channels have multiplex capability by programmble memory-
> mapped
> +register. All channels are split into two groups, called DMAMUX0 and
> DMAMUX1,
> +specific DMA request source can only be multiplexed by any channel of
> certain
> +group, DMAMUX0 or DMAMUX1, but not both.
> +
> +* eDMA Controller
> +Required properties:
> +- compatible :
> + - "fsl,vf610-edma" for eDMA used similar to that on Vybrid vf610
> SoC
> +- reg : Specifies base physical address(s) and size of the eDMA
> registers.
> + The 1st region is eDMA control register's address and size.
> + The 2nd and the 3rd regions are programmable channel multiplexing
> + control register's address and size.
> +- interrupts : Should contain eDMA interrupt
> +- interrupt-names : Should be "edma-tx" for transmission interrupt and
> + "edma-err" for error interrupt
> +- #dma-cells : Must be <2>.
> + The 1st cell specifies the DMAMUX(0 for DMAMUX0 and 1 for DMAMUX1).
> + Specific request source can only be multiplexed by specific
> channels
> + group called DMAMUX.
> + The 2nd cell specifies the request source(slot).
> + See include/dt-bindings/dma/<soc>-edma.h for all the supported
> + request sources.
> +- dma-channels : Number of channels supported by the controller
> +- clocks : Phandle of the DMA channel group block clock of the eDMA
> module
> +- clock-names : The channel group block clock names
> +
> +
> +Examples:
> +
> +edma0: dma-controller at 40018000 {
> + #dma-cells = <2>;
> + compatible = "fsl,vf610-edma";
> + reg = <0x40018000 0x2000>,
> + <0x40024000 0x1000>,
> + <0x40025000 0x1000>;
> + interrupts = <0 8 0x04>,
> + <0 9 0x04>;
> + interrupt-names = "edma-tx", "edma-err";
> + dma-channels = <32>;
> + clocks = <&clks VF610_CLK_DMAMUX0>,
> + <&clks VF610_CLK_DMAMUX1>;
> + clock-names = "dmamux0", "dmamux1";
> +};
> +
> +
> +* DMA clients
> +DMA client drivers that uses the DMA function must use the format
> described
> +in the dma.txt file, using a two-cell specifier for each channel: the
> 1st
> +specifies the channel group(DMAMUX) in which this request can be
> multiplexed,
> +and the 2nd specifies the request source.
> +
> +Examples:
> +
> +sai2: sai at 40031000 {
> + compatible = "fsl,vf610-sai";
> + reg = <0x40031000 0x1000>;
> + interrupts = <0 86 0x04>;
> + clocks = <&clks VF610_CLK_SAI2>;
> + clock-names = "sai";
> + dma-names = "tx", "rx";
> + dmas = <&edma0 VF610_EDMA_DMAMUX0 VF610_EDMA0_MUX0_SAI2_TX>,
> + <&edma0 VF610_EDMA_DMAMUX0 VF610_EDMA0_MUX0_SAI2_RX>;
> + status = "disabled";
> +};
> diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
> index c10eb89..7989c8c 100644
> --- a/drivers/dma/Kconfig
> +++ b/drivers/dma/Kconfig
> @@ -336,6 +336,16 @@ config K3_DMA
> Support the DMA engine for Hisilicon K3 platform
> devices.
>
> +config FSL_EDMA
> + tristate "Freescale eDMA engine support"
> + depends on OF
> + select DMA_ENGINE
> + select DMA_VIRTUAL_CHANNELS
> + help
> + Support the Freescale eDMA engine with DMAMUXs multiplexing
> + DMA request sources(slot) on eDMA engine channels.
> + This module can be found on Freescale Vybrid and LS-1 SoCs.
> +
> config DMA_ENGINE
> bool
>
> diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
> index 0ce2da9..68422af 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-$(CONFIG_FSL_EDMA) += fsl-edma.o
> diff --git a/drivers/dma/fsl-edma.c b/drivers/dma/fsl-edma.c
> new file mode 100644
> index 0000000..9dc27b4
> --- /dev/null
> +++ b/drivers/dma/fsl-edma.c
> @@ -0,0 +1,939 @@
> +/*
> + * drivers/dma/fsl-edma.c
> + *
> + * Copyright 2013-2014 Freescale Semiconductor, Inc.
> + *
> + * Driver for the Freescale eDMA engine with flexible channel
> multiplexing
> + * capability for DMA request sources. The eDMA block can be found on
> some
> + * Vybrid and Layerscape SoCs.
> + *
> + * 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 <linux/init.h>
> +#include <linux/module.h>
> +#include <linux/interrupt.h>
> +#include <linux/clk.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/dmapool.h>
> +#include <linux/slab.h>
> +#include <linux/spinlock.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_dma.h>
> +
> +#include "virt-dma.h"
> +
> +#define EDMA_CR 0x00
> +#define EDMA_ES 0x04
> +#define EDMA_ERQ 0x0C
> +#define EDMA_EEI 0x14
> +#define EDMA_SERQ 0x1B
> +#define EDMA_CERQ 0x1A
> +#define EDMA_SEEI 0x19
> +#define EDMA_CEEI 0x18
> +#define EDMA_CINT 0x1F
> +#define EDMA_CERR 0x1E
> +#define EDMA_SSRT 0x1D
> +#define EDMA_CDNE 0x1C
> +#define EDMA_INTR 0x24
> +#define EDMA_ERR 0x2C
> +
> +#define EDMA_TCD_SADDR(x) (0x1000 + 32 * (x))
> +#define EDMA_TCD_SOFF(x) (0x1004 + 32 * (x))
> +#define EDMA_TCD_ATTR(x) (0x1006 + 32 * (x))
> +#define EDMA_TCD_NBYTES(x) (0x1008 + 32 * (x))
> +#define EDMA_TCD_SLAST(x) (0x100C + 32 * (x))
> +#define EDMA_TCD_DADDR(x) (0x1010 + 32 * (x))
> +#define EDMA_TCD_DOFF(x) (0x1014 + 32 * (x))
> +#define EDMA_TCD_CITER_ELINK(x) (0x1016 + 32 * (x))
> +#define EDMA_TCD_CITER(x) (0x1016 + 32 * (x))
> +#define EDMA_TCD_DLAST_SGA(x) (0x1018 + 32 * (x))
> +#define EDMA_TCD_CSR(x) (0x101C + 32 * (x))
> +#define EDMA_TCD_BITER_ELINK(x) (0x101E + 32 * (x))
> +#define EDMA_TCD_BITER(x) (0x101E + 32 * (x))
> +
> +#define EDMA_CR_EDBG BIT(1)
> +#define EDMA_CR_ERCA BIT(2)
> +#define EDMA_CR_ERGA BIT(3)
> +#define EDMA_CR_HOE BIT(4)
> +#define EDMA_CR_HALT BIT(5)
> +#define EDMA_CR_CLM BIT(6)
> +#define EDMA_CR_EMLM BIT(7)
> +#define EDMA_CR_ECX BIT(16)
> +#define EDMA_CR_CX BIT(17)
> +
> +#define EDMA_SEEI_SEEI(x) ((x) & 0x1F)
> +#define EDMA_CEEI_CEEI(x) ((x) & 0x1F)
> +#define EDMA_CINT_CINT(x) ((x) & 0x1F)
> +#define EDMA_CERR_CERR(x) ((x) & 0x1F)
> +
> +#define EDMA_TCD_ATTR_DSIZE(x) (((x) & 0x0007))
> +#define EDMA_TCD_ATTR_DMOD(x) (((x) & 0x001F) << 3)
> +#define EDMA_TCD_ATTR_SSIZE(x) (((x) & 0x0007) << 8)
> +#define EDMA_TCD_ATTR_SMOD(x) (((x) & 0x001F) << 11)
> +#define EDMA_TCD_ATTR_SSIZE_8BIT (0x0000)
> +#define EDMA_TCD_ATTR_SSIZE_16BIT (0x0100)
> +#define EDMA_TCD_ATTR_SSIZE_32BIT (0x0200)
> +#define EDMA_TCD_ATTR_SSIZE_64BIT (0x0300)
> +#define EDMA_TCD_ATTR_SSIZE_32BYTE (0x0500)
> +#define EDMA_TCD_ATTR_DSIZE_8BIT (0x0000)
> +#define EDMA_TCD_ATTR_DSIZE_16BIT (0x0001)
> +#define EDMA_TCD_ATTR_DSIZE_32BIT (0x0002)
> +#define EDMA_TCD_ATTR_DSIZE_64BIT (0x0003)
> +#define EDMA_TCD_ATTR_DSIZE_32BYTE (0x0005)
> +
> +#define EDMA_TCD_SOFF_SOFF(x) (x)
> +#define EDMA_TCD_NBYTES_NBYTES(x) (x)
> +#define EDMA_TCD_SLAST_SLAST(x) (x)
> +#define EDMA_TCD_DADDR_DADDR(x) (x)
> +#define EDMA_TCD_CITER_CITER(x) ((x) & 0x7FFF)
> +#define EDMA_TCD_DOFF_DOFF(x) (x)
> +#define EDMA_TCD_DLAST_SGA_DLAST_SGA(x) (x)
> +#define EDMA_TCD_BITER_BITER(x) ((x) & 0x7FFF)
> +
> +#define EDMA_TCD_CSR_START BIT(0)
> +#define EDMA_TCD_CSR_INT_MAJOR BIT(1)
> +#define EDMA_TCD_CSR_INT_HALF BIT(2)
> +#define EDMA_TCD_CSR_D_REQ BIT(3)
> +#define EDMA_TCD_CSR_E_SG BIT(4)
> +#define EDMA_TCD_CSR_E_LINK BIT(5)
> +#define EDMA_TCD_CSR_ACTIVE BIT(6)
> +#define EDMA_TCD_CSR_DONE BIT(7)
> +
> +#define EDMAMUX_CHCFG_DIS 0x0
> +#define EDMAMUX_CHCFG_ENBL 0x80
> +#define EDMAMUX_CHCFG_SOURCE(n) ((n) & 0x3F)
> +
> +#define DMAMUX_NR 2
> +
> +struct fsl_edma_hw_tcd {
> + u32 saddr;
> + u16 soff;
> + u16 attr;
> + u32 nbytes;
> + u32 slast;
> + u32 daddr;
> + u16 doff;
> + u16 citer;
> + u32 dlast_sga;
> + u16 csr;
> + u16 biter;
> +} __packed;
> +
> +struct fsl_edma_sw_tcd {
> + dma_addr_t ptcd;
> + struct fsl_edma_hw_tcd *vtcd;
> +};
> +
> +struct fsl_edma_slave_config {
> + enum dma_transfer_direction dir;
> + enum dma_slave_buswidth addr_width;
> + u32 dev_addr;
> + u32 burst;
> + u32 attr;
> +};
> +
> +struct fsl_edma_chan {
> + struct virt_dma_chan vchan;
> + enum dma_status status;
> + struct fsl_edma_engine *edma;
> + struct fsl_edma_desc *edesc;
> + struct fsl_edma_slave_config fsc;
> + struct dma_pool *tcd_pool;
> +};
> +
> +struct fsl_edma_desc {
> + struct virt_dma_desc vdesc;
> + struct fsl_edma_chan *echan;
> + bool iscyclic;
> + unsigned int n_tcds;
> + struct fsl_edma_sw_tcd tcd[];
> +};
> +
> +struct fsl_edma_engine {
> + struct dma_device dma_dev;
> + void __iomem *membase;
> + void __iomem *muxbase[DMAMUX_NR];
> + struct clk *muxclk[DMAMUX_NR];
> + u32 n_chans;
> + int txirq;
> + int errirq;
> + bool big_endian;
> + struct fsl_edma_chan chans[];
> +};
> +
> +/* bytes swapping according to eDMA controller's endian */
> +#define EDMA_SWAP16(e, v) (__force u16)(e->big_endian ?
> cpu_to_be16(v) : cpu_to_le16(v))
> +#define EDMA_SWAP32(e, v) (__force u32)(e->big_endian ?
> cpu_to_be32(v) : cpu_to_le32(v))
> +
> +/*
> + * copying of ARM read{b,w,l) and write{b,w,l) macro definations
> + * except for doing default swap of cpu_to_le32, the bytes swap
> + * is done depending on eDMA controller's endian defination,
> + * which may be big-endian or little-endian.
> + */
> +static inline u8 edma_readb(void __iomem *addr)
> +{
> + return readb(addr);
> +}
> +
> +static inline u16 edma_readw(void __iomem *addr)
> +{
> + u16 __v = (__force u16) __raw_readw(addr);
> +
> + __iormb();
> + return __v;
> +}
> +
> +static inline u32 edma_readl(void __iomem *addr)
> +{
> + u32 __v = (__force u32) __raw_readl(addr);
> +
> + __iormb();
> + return __v;
> +}
> +
> +static inline void edma_writeb(u8 val, void __iomem *addr)
> +{
> + writeb(val, addr);
> +}
> +
> +static inline void edma_writew(u16 val, void __iomem *addr)
> +{
> + __iowmb();
> + __raw_writew((__force u16) val, addr);
> +}
> +
> +static inline void edma_writel(u32 val, void __iomem *addr)
> +{
> + __iowmb();
> + __raw_writel((__force u32) val, addr);
> +}
> +
> +static inline struct fsl_edma_chan *to_fsl_edma_chan(struct dma_chan
> *chan)
> +{
> + return container_of(chan, struct fsl_edma_chan, vchan.chan);
> +}
> +
> +static inline struct fsl_edma_desc *to_fsl_edma_desc(struct
> virt_dma_desc *vd)
> +{
> + return container_of(vd, struct fsl_edma_desc, vdesc);
> +}
> +
> +static inline void fsl_edma_enable_request(struct fsl_edma_chan
> *fsl_chan)
> +{
> + void __iomem *addr = fsl_chan->edma->membase;
> + u32 ch = fsl_chan->vchan.chan.chan_id;
> +
> + edma_writeb(EDMA_SEEI_SEEI(ch), addr + EDMA_SEEI);
> + edma_writeb(ch, addr + EDMA_SERQ);
> +}
> +
> +static inline void fsl_edma_disable_request(struct fsl_edma_chan
> *fsl_chan)
> +{
> + void __iomem *addr = fsl_chan->edma->membase;
> + u32 ch = fsl_chan->vchan.chan.chan_id;
> +
> + edma_writeb(ch, addr + EDMA_CERQ);
> + edma_writeb(EDMA_CEEI_CEEI(ch), addr + EDMA_CEEI);
> +}
> +
> +static inline void fsl_edma_chan_mux(struct fsl_edma_chan *fsl_chan,
> + unsigned int slot, bool enable)
> +{
> + u32 ch = fsl_chan->vchan.chan.chan_id;
> + void __iomem *muxaddr = fsl_chan->edma->muxbase[ch / DMAMUX_NR];
> + unsigned chans_per_mux, ch_off;
> +
> + chans_per_mux = fsl_chan->edma->n_chans / DMAMUX_NR;
> + ch_off = fsl_chan->vchan.chan.chan_id % chans_per_mux;
> +
> + if (enable)
> + edma_writeb(EDMAMUX_CHCFG_ENBL | EDMAMUX_CHCFG_SOURCE(slot),
> + muxaddr + ch_off);
> + else
> + edma_writeb(EDMAMUX_CHCFG_DIS, muxaddr + ch_off);
> +}
> +
> +static unsigned int fsl_edma_get_tcd_attr(enum dma_slave_buswidth
> addr_width)
> +{
> + switch (addr_width) {
> + case 1:
> + return EDMA_TCD_ATTR_SSIZE_8BIT | EDMA_TCD_ATTR_DSIZE_8BIT;
> + case 2:
> + return EDMA_TCD_ATTR_SSIZE_16BIT | EDMA_TCD_ATTR_DSIZE_16BIT;
> + case 4:
> + return EDMA_TCD_ATTR_SSIZE_32BIT | EDMA_TCD_ATTR_DSIZE_32BIT;
> + case 8:
> + return EDMA_TCD_ATTR_SSIZE_64BIT | EDMA_TCD_ATTR_DSIZE_64BIT;
> + default:
> + return EDMA_TCD_ATTR_SSIZE_32BIT | EDMA_TCD_ATTR_DSIZE_32BIT;
> + }
> +}
> +
> +static void fsl_edma_free_desc(struct virt_dma_desc *vdesc)
> +{
> + struct fsl_edma_desc *fsl_desc;
> + int i;
> +
> + fsl_desc = to_fsl_edma_desc(vdesc);
> + for (i = 0; i < fsl_desc->n_tcds; i++)
> + dma_pool_free(fsl_desc->echan->tcd_pool,
> + fsl_desc->tcd[i].vtcd,
> + fsl_desc->tcd[i].ptcd);
> + kfree(fsl_desc);
> +}
> +
> +static int fsl_edma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
> + unsigned long arg)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> + struct dma_slave_config *cfg = (void *)arg;
> + unsigned long flags;
> + LIST_HEAD(head);
> +
> + switch (cmd) {
> + case DMA_TERMINATE_ALL:
> + spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
> + fsl_edma_disable_request(fsl_chan);
> + fsl_chan->edesc = NULL;
> + vchan_get_all_descriptors(&fsl_chan->vchan, &head);
> + spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
> + vchan_dma_desc_free_list(&fsl_chan->vchan, &head);
> + return 0;
> +
> + case DMA_SLAVE_CONFIG:
> + fsl_chan->fsc.dir = cfg->direction;
> + if (cfg->direction == DMA_DEV_TO_MEM) {
> + fsl_chan->fsc.dev_addr = cfg->src_addr;
> + fsl_chan->fsc.addr_width = cfg->src_addr_width;
> + fsl_chan->fsc.burst = cfg->src_maxburst;
> + fsl_chan->fsc.attr = fsl_edma_get_tcd_attr(cfg-
> >src_addr_width);
> + } else if (cfg->direction == DMA_MEM_TO_DEV) {
> + fsl_chan->fsc.dev_addr = cfg->dst_addr;
> + fsl_chan->fsc.addr_width = cfg->dst_addr_width;
> + fsl_chan->fsc.burst = cfg->dst_maxburst;
> + fsl_chan->fsc.attr = fsl_edma_get_tcd_attr(cfg-
> >dst_addr_width);
> + } else {
> + return -EINVAL;
> + }
> + return 0;
> +
> + case DMA_PAUSE:
> + spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
> + if (fsl_chan->edesc) {
> + fsl_edma_disable_request(fsl_chan);
> + fsl_chan->status = DMA_PAUSED;
> + }
> + spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
> + return 0;
> +
> + case DMA_RESUME:
> + spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
> + if (fsl_chan->edesc) {
> + fsl_edma_enable_request(fsl_chan);
> + fsl_chan->status = DMA_IN_PROGRESS;
> + }
> + spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
> + return 0;
> +
> + default:
> + return -ENXIO;
> + }
> +}
> +
> +static size_t fsl_edma_desc_residue(struct fsl_edma_chan *fsl_chan,
> + struct virt_dma_desc *vdesc, bool in_progress)
> +{
> + struct fsl_edma_desc *edesc = fsl_chan->edesc;
> + void __iomem *addr = fsl_chan->edma->membase;
> + u32 ch = fsl_chan->vchan.chan.chan_id;
> + enum dma_transfer_direction dir = fsl_chan->fsc.dir;
> + dma_addr_t cur_addr, dma_addr;
> + size_t len, size;
> + int i;
> +
> + /* calculate the total size in this desc */
> + for (len = i = 0; i < fsl_chan->edesc->n_tcds; i++)
> + len += edesc->tcd[i].vtcd->nbytes * edesc->tcd[i].vtcd->biter;
> +
> + if (!in_progress)
> + return len;
> +
> + if (dir == DMA_MEM_TO_DEV)
> + cur_addr = EDMA_SWAP32(fsl_chan->edma, edma_readl(addr +
> EDMA_TCD_SADDR(ch)));
> + else
> + cur_addr = EDMA_SWAP32(fsl_chan->edma, edma_readl(addr +
> EDMA_TCD_DADDR(ch)));
> +
> + /* figure out the finished and calculate the residue */
> + for (i = 0; i < fsl_chan->edesc->n_tcds; i++) {
> + size = edesc->tcd[i].vtcd->nbytes * edesc->tcd[i].vtcd->biter;
> + if (dir == DMA_MEM_TO_DEV)
> + dma_addr = edesc->tcd[i].vtcd->saddr;
> + else
> + dma_addr = edesc->tcd[i].vtcd->daddr;
> +
> + len -= size;
> + if (cur_addr > dma_addr && cur_addr < dma_addr + size) {
> + len += dma_addr + size - cur_addr;
> + break;
> + }
> + }
> +
> + return len;
> +}
> +
> +static enum dma_status fsl_edma_tx_status(struct dma_chan *chan,
> + dma_cookie_t cookie, struct dma_tx_state *txstate)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> + struct virt_dma_desc *vdesc;
> + enum dma_status status;
> + unsigned long flags;
> +
> + status = dma_cookie_status(chan, cookie, txstate);
> + if (status == DMA_COMPLETE)
> + return status;
> +
> + if (!txstate)
> + return fsl_chan->status;
> +
> + spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
> + vdesc = vchan_find_desc(&fsl_chan->vchan, cookie);
> + if (fsl_chan->edesc && cookie == fsl_chan->edesc->vdesc.tx.cookie)
> + txstate->residue = fsl_edma_desc_residue(fsl_chan, vdesc,
> true);
> + else if (vdesc)
> + txstate->residue = fsl_edma_desc_residue(fsl_chan, vdesc,
> false);
> + else
> + txstate->residue = 0;
> +
> + spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
> +
> + return fsl_chan->status;
> +}
> +
> +static void fsl_edma_set_tcd_params(struct fsl_edma_chan *fsl_chan,
> + u32 src, u32 dst, u16 attr, u16 soff, u32 nbytes,
> + u32 slast, u16 citer, u16 biter, u32 doff, u32 dlast_sga,
> + u16 csr)
> +{
> + void __iomem *addr = fsl_chan->edma->membase;
> + u32 ch = fsl_chan->vchan.chan.chan_id;
> +
> + edma_writew(0, addr + EDMA_TCD_CSR(ch));
> + edma_writel(src, addr + EDMA_TCD_SADDR(ch));
> + edma_writel(dst, addr + EDMA_TCD_DADDR(ch));
> + edma_writew(attr, addr + EDMA_TCD_ATTR(ch));
> + edma_writew(soff, addr + EDMA_TCD_SOFF(ch));
> + edma_writel(nbytes, addr + EDMA_TCD_NBYTES(ch));
> + edma_writel(slast, addr + EDMA_TCD_SLAST(ch));
> + edma_writew(citer, addr + EDMA_TCD_CITER(ch));
> + edma_writew(biter, addr + EDMA_TCD_BITER(ch));
> + edma_writew(doff, addr + EDMA_TCD_DOFF(ch));
> + edma_writel(dlast_sga, addr + EDMA_TCD_DLAST_SGA(ch));
> + edma_writew(csr, addr + EDMA_TCD_CSR(ch));
> +}
> +
> +static void fill_tcd_params(struct fsl_edma_engine *edma,
> + struct fsl_edma_hw_tcd *tcd, u32 src, u32 dst,
> + u16 attr, u16 soff, u32 nbytes, u32 slast, u16 citer,
> + u16 biter, u16 doff, u32 dlast_sga, bool major_int,
> + bool disable_req, bool enable_sg)
> +{
> + u16 csr = 0;
> +
> + tcd->saddr = EDMA_SWAP32(edma, src);
> + tcd->daddr = EDMA_SWAP32(edma, dst);
> + tcd->attr = EDMA_SWAP16(edma, attr);
> + tcd->soff = EDMA_SWAP16(edma, EDMA_TCD_SOFF_SOFF(soff));
> + tcd->nbytes = EDMA_SWAP32(edma, EDMA_TCD_NBYTES_NBYTES(nbytes));
> + tcd->slast = EDMA_SWAP32(edma, EDMA_TCD_SLAST_SLAST(slast));
> + tcd->citer = EDMA_SWAP16(edma, EDMA_TCD_CITER_CITER(citer));
> + tcd->doff = EDMA_SWAP16(edma, EDMA_TCD_DOFF_DOFF(doff));
> + tcd->dlast_sga = EDMA_SWAP32(edma,
> EDMA_TCD_DLAST_SGA_DLAST_SGA(dlast_sga));
> + tcd->biter = EDMA_SWAP16(edma, EDMA_TCD_BITER_BITER(biter));
> + if (major_int)
> + csr |= EDMA_TCD_CSR_INT_MAJOR;
> +
> + if (disable_req)
> + csr |= EDMA_TCD_CSR_D_REQ;
> +
> + if (enable_sg)
> + csr |= EDMA_TCD_CSR_E_SG;
> + tcd->csr = EDMA_SWAP16(edma, csr);
> +}
> +
> +static struct fsl_edma_desc *fsl_edma_alloc_desc(struct fsl_edma_chan
> *fsl_chan,
> + int sg_len)
> +{
> + struct fsl_edma_desc *fsl_desc;
> + int i;
> +
> + fsl_desc = kzalloc(sizeof(*fsl_desc) + sizeof(struct
> fsl_edma_sw_tcd) * sg_len,
> + GFP_NOWAIT);
> + if (!fsl_desc)
> + return NULL;
> +
> + fsl_desc->echan = fsl_chan;
> + fsl_desc->n_tcds = sg_len;
> + for (i = 0; i < sg_len; i++) {
> + fsl_desc->tcd[i].vtcd = dma_pool_alloc(fsl_chan->tcd_pool,
> + GFP_NOWAIT, &fsl_desc->tcd[i].ptcd);
> + if (!fsl_desc->tcd[i].vtcd)
> + goto free_on_err;
> + }
> + return fsl_desc;
> +
> +free_on_err:
> + while (--i >= 0)
> + dma_pool_free(fsl_chan->tcd_pool, fsl_desc->tcd[i].vtcd,
> + fsl_desc->tcd[i].ptcd);
> + kfree(fsl_desc);
> + return NULL;
> +}
> +
> +static struct dma_async_tx_descriptor *fsl_edma_prep_dma_cyclic(
> + struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
> + size_t period_len, enum dma_transfer_direction direction,
> + unsigned long flags, void *context)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> + struct fsl_edma_desc *fsl_desc;
> + dma_addr_t dma_buf_next;
> + int sg_len, i;
> + u32 src_addr, dst_addr, last_sg, nbytes;
> + u16 soff, doff, iter;
> +
> + if (!is_slave_direction(fsl_chan->fsc.dir))
> + return NULL;
> +
> + sg_len = buf_len / period_len;
> + fsl_desc = fsl_edma_alloc_desc(fsl_chan, sg_len);
> + if (!fsl_desc)
> + return NULL;
> + fsl_desc->iscyclic = true;
> +
> + dma_buf_next = dma_addr;
> + nbytes = fsl_chan->fsc.addr_width * fsl_chan->fsc.burst;
> + iter = period_len / nbytes;
> + for (i = 0; i < sg_len; i++) {
> + if (dma_buf_next >= dma_addr + buf_len)
> + dma_buf_next = dma_addr;
> +
> + /* get next sg's physical address */
> + last_sg = fsl_desc->tcd[(i + 1) % sg_len].ptcd;
> +
> + if (fsl_chan->fsc.dir == DMA_MEM_TO_DEV) {
> + src_addr = dma_buf_next;
> + dst_addr = fsl_chan->fsc.dev_addr;
> + soff = fsl_chan->fsc.addr_width;
> + doff = 0;
> + } else {
> + src_addr = fsl_chan->fsc.dev_addr;
> + dst_addr = dma_buf_next;
> + soff = 0;
> + doff = fsl_chan->fsc.addr_width;
> + }
> +
> + fill_tcd_params(fsl_chan->edma, fsl_desc->tcd[i].vtcd,
> src_addr,
> + dst_addr, fsl_chan->fsc.attr, soff, nbytes, 0,
> + iter, iter, doff, last_sg, true, false, true);
> + dma_buf_next += period_len;
> + }
> +
> + return vchan_tx_prep(&fsl_chan->vchan, &fsl_desc->vdesc, flags);
> +}
> +
> +static struct dma_async_tx_descriptor *fsl_edma_prep_slave_sg(
> + struct dma_chan *chan, struct scatterlist *sgl,
> + unsigned int sg_len, enum dma_transfer_direction direction,
> + unsigned long flags, void *context)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> + struct fsl_edma_desc *fsl_desc;
> + struct scatterlist *sg;
> + u32 src_addr, dst_addr, last_sg, nbytes;
> + u16 soff, doff, iter;
> + int i;
> +
> + if (!is_slave_direction(fsl_chan->fsc.dir))
> + return NULL;
> +
> + fsl_desc = fsl_edma_alloc_desc(fsl_chan, sg_len);
> + if (!fsl_desc)
> + return NULL;
> + fsl_desc->iscyclic = false;
> +
> + nbytes = fsl_chan->fsc.addr_width * fsl_chan->fsc.burst;
> + for_each_sg(sgl, sg, sg_len, i) {
> + /* get next sg's physical address */
> + last_sg = fsl_desc->tcd[(i + 1) % sg_len].ptcd;
> +
> + if (fsl_chan->fsc.dir == DMA_MEM_TO_DEV) {
> + src_addr = sg_dma_address(sg);
> + dst_addr = fsl_chan->fsc.dev_addr;
> + soff = fsl_chan->fsc.addr_width;
> + doff = 0;
> + } else {
> + src_addr = fsl_chan->fsc.dev_addr;
> + dst_addr = sg_dma_address(sg);
> + soff = 0;
> + doff = fsl_chan->fsc.addr_width;
> + }
> +
> + iter = sg_dma_len(sg) / nbytes;
> + if (i < sg_len - 1) {
> + last_sg = fsl_desc->tcd[(i + 1)].ptcd;
> + fill_tcd_params(fsl_chan->edma, fsl_desc->tcd[i].vtcd,
> + src_addr, dst_addr, fsl_chan->fsc.attr,
> + soff, nbytes, 0, iter, iter, doff, last_sg,
> + false, false, true);
> + } else {
> + last_sg = 0;
> + fill_tcd_params(fsl_chan->edma, fsl_desc->tcd[i].vtcd,
> + src_addr, dst_addr, fsl_chan->fsc.attr,
> + soff, nbytes, 0, iter, iter, doff, last_sg,
> + true, true, false);
> + }
> + }
> +
> + return vchan_tx_prep(&fsl_chan->vchan, &fsl_desc->vdesc, flags);
> +}
> +
> +static void fsl_edma_xfer_desc(struct fsl_edma_chan *fsl_chan)
> +{
> + struct fsl_edma_hw_tcd *tcd;
> + struct virt_dma_desc *vdesc;
> +
> + vdesc = vchan_next_desc(&fsl_chan->vchan);
> + if (!vdesc)
> + return;
> + fsl_chan->edesc = to_fsl_edma_desc(vdesc);
> + tcd = fsl_chan->edesc->tcd[0].vtcd;
> + fsl_edma_set_tcd_params(fsl_chan, tcd->saddr, tcd->daddr, tcd->attr,
> + tcd->soff, tcd->nbytes, tcd->slast, tcd->citer,
> + tcd->biter, tcd->doff, tcd->dlast_sga, tcd->csr);
> + fsl_edma_enable_request(fsl_chan);
> + fsl_chan->status = DMA_IN_PROGRESS;
> +}
> +
> +static irqreturn_t fsl_edma_tx_handler(int irq, void *dev_id)
> +{
> + struct fsl_edma_engine *fsl_edma = dev_id;
> + unsigned int intr, ch;
> + void __iomem *base_addr;
> + struct fsl_edma_chan *fsl_chan;
> +
> + base_addr = fsl_edma->membase;
> +
> + intr = EDMA_SWAP32(fsl_edma, edma_readl(base_addr + EDMA_INTR));
> + if (!intr)
> + return IRQ_NONE;
> +
> + for (ch = 0; ch < fsl_edma->n_chans; ch++) {
> + if (intr & (0x1 << ch)) {
> + edma_writeb(EDMA_CINT_CINT(ch), base_addr + EDMA_CINT);
> +
> + fsl_chan = &fsl_edma->chans[ch];
> +
> + spin_lock(&fsl_chan->vchan.lock);
> + if (!fsl_chan->edesc->iscyclic) {
> + list_del(&fsl_chan->edesc->vdesc.node);
> + vchan_cookie_complete(&fsl_chan->edesc->vdesc);
> + fsl_chan->edesc = NULL;
> + fsl_chan->status = DMA_COMPLETE;
> + } else {
> + vchan_cyclic_callback(&fsl_chan->edesc->vdesc);
> + }
> +
> + if (!fsl_chan->edesc)
> + fsl_edma_xfer_desc(fsl_chan);
> +
> + spin_unlock(&fsl_chan->vchan.lock);
> + }
> + }
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t fsl_edma_err_handler(int irq, void *dev_id)
> +{
> + struct fsl_edma_engine *fsl_edma = dev_id;
> + unsigned int err, ch;
> +
> + err = EDMA_SWAP32(fsl_edma, edma_readl(fsl_edma->membase +
> EDMA_ERR));
> + if (!err)
> + return IRQ_NONE;
> +
> + for (ch = 0; ch < fsl_edma->n_chans; ch++) {
> + if (err & (0x1 << ch)) {
> + fsl_edma_disable_request(&fsl_edma->chans[ch]);
> + edma_writeb(EDMA_CERR_CERR(ch), fsl_edma->membase +
> EDMA_CERR);
> + fsl_edma->chans[ch].status = DMA_ERROR;
> + }
> + }
> + return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id)
> +{
> + if (fsl_edma_tx_handler(irq, dev_id) == IRQ_HANDLED)
> + return IRQ_HANDLED;
> +
> + return fsl_edma_err_handler(irq, dev_id);
> +}
> +
> +static void fsl_edma_issue_pending(struct dma_chan *chan)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> + unsigned long flags;
> +
> + spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
> +
> + if (vchan_issue_pending(&fsl_chan->vchan) && !fsl_chan->edesc)
> + fsl_edma_xfer_desc(fsl_chan);
> +
> + spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
> +}
> +
> +static bool fsl_edma_filter_fn(struct dma_chan *chan, void *mux)
> +{
> + return (chan->chan_id / DMAMUX_NR) == (u32)mux;
> +}
> +
> +static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
> + struct of_dma *ofdma)
> +{
> + struct dma_chan *chan;
> + dma_cap_mask_t mask;
> +
> + if (dma_spec->args_count != 2)
> + return NULL;
> +
> + dma_cap_zero(mask);
> + dma_cap_set(DMA_SLAVE, mask);
> + dma_cap_set(DMA_CYCLIC, mask);
> + chan = dma_request_channel(mask, fsl_edma_filter_fn, (void
> *)dma_spec->args[0]);
> + if (chan)
> + fsl_edma_chan_mux(to_fsl_edma_chan(chan), dma_spec->args[1],
> true);
> + return chan;
> +}
> +
> +static int fsl_edma_alloc_chan_resources(struct dma_chan *chan)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> +
> + fsl_chan->tcd_pool = dma_pool_create("tcd_pool", chan->device->dev,
> + sizeof(struct fsl_edma_hw_tcd),
> + 32, 0);
> + return 0;
> +}
> +
> +static void fsl_edma_free_chan_resources(struct dma_chan *chan)
> +{
> + struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
> + unsigned long flags;
> + LIST_HEAD(head);
> +
> + spin_lock_irqsave(&fsl_chan->vchan.lock, flags);
> + fsl_edma_disable_request(fsl_chan);
> + fsl_edma_chan_mux(fsl_chan, 0, false);
> + fsl_chan->edesc = NULL;
> + vchan_get_all_descriptors(&fsl_chan->vchan, &head);
> + spin_unlock_irqrestore(&fsl_chan->vchan.lock, flags);
> +
> + vchan_dma_desc_free_list(&fsl_chan->vchan, &head);
> + dma_pool_destroy(fsl_chan->tcd_pool);
> + fsl_chan->tcd_pool = NULL;
> +}
> +
> +static int
> +fsl_edma_irq_init(struct platform_device *pdev, struct fsl_edma_engine
> *fsl_edma)
> +{
> + int ret;
> +
> + fsl_edma->txirq = platform_get_irq_byname(pdev, "edma-tx");
> + if (fsl_edma->txirq < 0) {
> + dev_err(&pdev->dev, "Can't get edma-tx irq.\n");
> + return fsl_edma->txirq;
> + }
> +
> + fsl_edma->errirq = platform_get_irq_byname(pdev, "edma-err");
> + if (fsl_edma->errirq < 0) {
> + dev_err(&pdev->dev, "Can't get edma-err irq.\n");
> + return fsl_edma->errirq;
> + }
> +
> + if (fsl_edma->txirq == fsl_edma->errirq) {
> + ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
> + fsl_edma_irq_handler, 0, "eDMA", fsl_edma);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't register eDMA IRQ.\n");
> + return ret;
> + }
> + } else {
> + ret = devm_request_irq(&pdev->dev, fsl_edma->txirq,
> + fsl_edma_tx_handler, 0, "eDMA tx", fsl_edma);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
> + return ret;
> + }
> +
> + ret = devm_request_irq(&pdev->dev, fsl_edma->errirq,
> + fsl_edma_err_handler, 0, "eDMA err", fsl_edma);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't register eDMA err IRQ.\n");
> + return ret;
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int fsl_edma_probe(struct platform_device *pdev)
> +{
> + struct device_node *np = pdev->dev.of_node;
> + struct fsl_edma_engine *fsl_edma;
> + struct fsl_edma_chan *fsl_chan;
> + struct resource *res;
> + int len, chans;
> + int ret, i;
> +
> + ret = of_property_read_u32(np, "dma-channels", &chans);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't get dma-channels.\n");
> + return ret;
> + }
> +
> + len = sizeof(*fsl_edma) + sizeof(*fsl_chan) * chans;
> + fsl_edma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL);
> + if (!fsl_edma)
> + return -ENOMEM;
> +
> + fsl_edma->n_chans = chans;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + fsl_edma->membase = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(fsl_edma->membase))
> + return PTR_ERR(fsl_edma->membase);
> +
> + for (i = 0; i < DMAMUX_NR; i++) {
> + char clkname[32];
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 1 + i);
> + fsl_edma->muxbase[i] = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(fsl_edma->muxbase[i]))
> + return PTR_ERR(fsl_edma->muxbase[i]);
> +
> + sprintf(clkname, "dmamux%d", i);
> + fsl_edma->muxclk[i] = of_clk_get(np, i);
> + fsl_edma->muxclk[i] = devm_clk_get(&pdev->dev, clkname);
> + if (IS_ERR(fsl_edma->muxclk[i])) {
> + dev_err(&pdev->dev, "Missing DMAMUX block clock.\n");
> + return PTR_ERR(fsl_edma->muxclk[i]);
> + }
> +
> + ret = clk_prepare_enable(fsl_edma->muxclk[i]);
> + if (ret) {
> + dev_err(&pdev->dev, "DMAMUX clk block failed.\n");
> + return ret;
> + }
> +
> + }
> +
> + ret = fsl_edma_irq_init(pdev, fsl_edma);
> + if (ret)
> + return ret;
> +
> + fsl_edma->big_endian = of_property_read_bool(np, "big-endian");
> +
> + INIT_LIST_HEAD(&fsl_edma->dma_dev.channels);
> + for (i = 0; i < fsl_edma->n_chans; i++) {
> + struct fsl_edma_chan *fsl_chan = &fsl_edma->chans[i];
> +
> + fsl_chan->edma = fsl_edma;
> +
> + fsl_chan->vchan.desc_free = fsl_edma_free_desc;
> + vchan_init(&fsl_chan->vchan, &fsl_edma->dma_dev);
> +
> + edma_writew(0x0, fsl_edma->membase + EDMA_TCD_CSR(i));
> + fsl_edma_chan_mux(fsl_chan, 0, false);
> + }
> +
> + dma_cap_set(DMA_SLAVE, fsl_edma->dma_dev.cap_mask);
> + dma_cap_set(DMA_CYCLIC, fsl_edma->dma_dev.cap_mask);
> +
> + fsl_edma->dma_dev.dev = &pdev->dev;
> + fsl_edma->dma_dev.device_alloc_chan_resources
> + = fsl_edma_alloc_chan_resources;
> + fsl_edma->dma_dev.device_free_chan_resources
> + = fsl_edma_free_chan_resources;
> + fsl_edma->dma_dev.device_tx_status = fsl_edma_tx_status;
> + fsl_edma->dma_dev.device_prep_slave_sg = fsl_edma_prep_slave_sg;
> + fsl_edma->dma_dev.device_prep_dma_cyclic = fsl_edma_prep_dma_cyclic;
> + fsl_edma->dma_dev.device_control = fsl_edma_control;
> + fsl_edma->dma_dev.device_issue_pending = fsl_edma_issue_pending;
> +
> + platform_set_drvdata(pdev, fsl_edma);
> +
> + ret = dma_async_device_register(&fsl_edma->dma_dev);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't register Freescale eDMA
> engine.\n");
> + return ret;
> + }
> +
> + ret = of_dma_controller_register(np, fsl_edma_xlate, fsl_edma);
> + if (ret) {
> + dev_err(&pdev->dev, "Can't register Freescale eDMA
> of_dma.\n");
> + dma_async_device_unregister(&fsl_edma->dma_dev);
> + return ret;
> + }
> +
> + /* enable round robin arbitration */
> + edma_writel(EDMA_SWAP32(fsl_edma, EDMA_CR_ERGA | EDMA_CR_ERCA),
> + fsl_edma->membase + EDMA_CR);
> +
> + return 0;
> +}
> +
> +static int fsl_edma_remove(struct platform_device *pdev)
> +{
> + struct device_node *np = pdev->dev.of_node;
> + struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev);
> + int i;
> +
> + of_dma_controller_free(np);
> + dma_async_device_unregister(&fsl_edma->dma_dev);
> +
> + for (i = 0; i < DMAMUX_NR; i++)
> + clk_disable_unprepare(fsl_edma->muxclk[i]);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id fsl_edma_dt_ids[] = {
> + { .compatible = "fsl,vf610-edma", },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, fsl_edma_dt_ids);
> +
> +static struct platform_driver fsl_edma_driver = {
> + .driver = {
> + .name = "fsl-edma",
> + .owner = THIS_MODULE,
> + .of_match_table = fsl_edma_dt_ids,
> + },
> + .probe = fsl_edma_probe,
> + .remove = fsl_edma_remove,
> +};
> +
> +module_platform_driver(fsl_edma_driver);
> +
> +MODULE_ALIAS("platform:fsl-edma");
> +MODULE_DESCRIPTION("Freescale eDMA engine driver");
> +MODULE_LICENSE("GPL v2");
> --
> 1.8.0
>
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