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Subject[PATCHv9 2/2] dma: Add Freescale eDMA engine driver support
Date
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@freescale.com>
Signed-off-by: Jingchang Lu <b35083@freescale.com>
---
changes in v9:
define endian's operating functions instead of macro definition.
remove the filter function, using dma_get_slave_channel instead.

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 | 66 ++
drivers/dma/Kconfig | 10 +
drivers/dma/Makefile | 1 +
drivers/dma/fsl-edma.c | 957 +++++++++++++++++++++
4 files changed, 1034 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..5a5fb61
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/fsl-edma.txt
@@ -0,0 +1,66 @@
+* Freescale enhanced Direct Memory Access(eDMA) Controller
+
+ The eDMA channels have multiplex capability by programmble memory-mapped
+registers. 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) ID.
+ See the SoC's reference manual for all the supported request sources.
+- dma-channels : Number of channels supported by the controller
+- clock-names : The channel group block clock names
+- clocks : eDMA module clock
+
+
+Examples:
+
+edma0: dma-controller@40018000 {
+ #dma-cells = <2>;
+ compatible = "fsl,vf610-edma";
+ reg = <0x40018000 0x2000>,
+ <0x40024000 0x1000>,
+ <0x40025000 0x1000>;
+ interrupts = <0 8 IRQ_TYPE_LEVEL_HIGH>,
+ <0 9 IRQ_TYPE_LEVEL_HIGH>;
+ interrupt-names = "edma-tx", "edma-err";
+ dma-channels = <32>;
+ clock-names = "dmamux0", "dmamux1";
+ clocks = <&clks VF610_CLK_DMAMUX0>,
+ <&clks VF610_CLK_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@40031000 {
+ compatible = "fsl,vf610-sai";
+ reg = <0x40031000 0x1000>;
+ interrupts = <0 86 IRQ_TYPE_LEVEL_HIGH>;
+ clock-names = "sai";
+ clocks = <&clks VF610_CLK_SAI2>;
+ dma-names = "tx", "rx";
+ dmas = <&edma0 0 21>,
+ <&edma0 0 20>;
+ status = "disabled";
+};
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 9ae6f54..3d8a522 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -342,6 +342,16 @@ 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 programmable channel
+ multiplexing capability for DMA request sources(slot).
+ 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 0a6f08e..e39c56b 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -43,3 +43,4 @@ 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..7e6cd11
--- /dev/null
+++ b/drivers/dma/fsl-edma.c
@@ -0,0 +1,957 @@
+/*
+ * 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
+
+static DEFINE_MUTEX(fsl_edma_mutex);
+
+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;
+};
+
+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[];
+};
+
+/*
+ * R/W functions for big- or little-endian registers
+ * the eDMA controller's endian is independent of the CPU core's endian.
+ */
+
+static u16 edma_readw(struct fsl_edma_engine *edma, void __iomem *addr)
+{
+ if (edma->big_endian)
+ return ioread16be(addr);
+ else
+ return ioread16(addr);
+}
+
+static u32 edma_readl(struct fsl_edma_engine *edma, void __iomem *addr)
+{
+ if (edma->big_endian)
+ return ioread32be(addr);
+ else
+ return ioread32(addr);
+}
+
+static void edma_writeb(struct fsl_edma_engine *edma, u8 val, void __iomem *addr)
+{
+ iowrite8(val, addr);
+}
+
+static void edma_writew(struct fsl_edma_engine *edma, u16 val, void __iomem *addr)
+{
+ if (edma->big_endian)
+ iowrite16be(val, addr);
+ else
+ iowrite16(val, addr);
+}
+
+static void edma_writel(struct fsl_edma_engine *edma, u32 val, void __iomem *addr)
+{
+ if (edma->big_endian)
+ iowrite32be(val, addr);
+ else
+ iowrite32(val, addr);
+}
+
+static struct fsl_edma_chan *to_fsl_edma_chan(struct dma_chan *chan)
+{
+ return container_of(chan, struct fsl_edma_chan, vchan.chan);
+}
+
+static struct fsl_edma_desc *to_fsl_edma_desc(struct virt_dma_desc *vd)
+{
+ return container_of(vd, struct fsl_edma_desc, vdesc);
+}
+
+static 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(fsl_chan->edma, EDMA_SEEI_SEEI(ch), addr + EDMA_SEEI);
+ edma_writeb(fsl_chan->edma, ch, addr + EDMA_SERQ);
+}
+
+static 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(fsl_chan->edma, ch, addr + EDMA_CERQ);
+ edma_writeb(fsl_chan->edma, EDMA_CEEI_CEEI(ch), addr + EDMA_CEEI);
+}
+
+static 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(fsl_chan->edma,
+ EDMAMUX_CHCFG_ENBL | EDMAMUX_CHCFG_SOURCE(slot),
+ muxaddr + ch_off);
+ else
+ edma_writeb(fsl_chan->edma, 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 += edma_readl(fsl_chan->edma, &(edesc->tcd[i].vtcd->nbytes))
+ * edma_readw(fsl_chan->edma, &(edesc->tcd[i].vtcd->biter));
+
+ if (!in_progress)
+ return len;
+
+ if (dir == DMA_MEM_TO_DEV)
+ cur_addr = edma_readl(fsl_chan->edma, addr + EDMA_TCD_SADDR(ch));
+ else
+ cur_addr = edma_readl(fsl_chan->edma, addr + EDMA_TCD_DADDR(ch));
+
+ /* figure out the finished and calculate the residue */
+ for (i = 0; i < fsl_chan->edesc->n_tcds; i++) {
+ size = edma_readl(fsl_chan->edma, &(edesc->tcd[i].vtcd->nbytes))
+ * edma_readw(fsl_chan->edma, &(edesc->tcd[i].vtcd->biter));
+ if (dir == DMA_MEM_TO_DEV)
+ dma_addr = edma_readl(fsl_chan->edma,
+ &(edesc->tcd[i].vtcd->saddr));
+ else
+ dma_addr = edma_readl(fsl_chan->edma,
+ &(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;
+
+ /*
+ * TCD parameters have been swapped in fill_tcd_params(),
+ * so just write them to registers in the cpu endian here
+ */
+ writew(0, addr + EDMA_TCD_CSR(ch));
+ writel(src, addr + EDMA_TCD_SADDR(ch));
+ writel(dst, addr + EDMA_TCD_DADDR(ch));
+ writew(attr, addr + EDMA_TCD_ATTR(ch));
+ writew(soff, addr + EDMA_TCD_SOFF(ch));
+ writel(nbytes, addr + EDMA_TCD_NBYTES(ch));
+ writel(slast, addr + EDMA_TCD_SLAST(ch));
+ writew(citer, addr + EDMA_TCD_CITER(ch));
+ writew(biter, addr + EDMA_TCD_BITER(ch));
+ writew(doff, addr + EDMA_TCD_DOFF(ch));
+ writel(dlast_sga, addr + EDMA_TCD_DLAST_SGA(ch));
+ 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;
+
+ /*
+ * eDMA hardware SGs require the TCD parameters stored in memory
+ * the same endian as the eDMA module so that they can be loaded
+ * automatically by the engine
+ */
+ edma_writel(edma, src, &(tcd->saddr));
+ edma_writel(edma, dst, &(tcd->daddr));
+ edma_writew(edma, attr, &(tcd->attr));
+ edma_writew(edma, EDMA_TCD_SOFF_SOFF(soff), &(tcd->soff));
+ edma_writel(edma, EDMA_TCD_NBYTES_NBYTES(nbytes), &(tcd->nbytes));
+ edma_writel(edma, EDMA_TCD_SLAST_SLAST(slast), &(tcd->slast));
+ edma_writew(edma, EDMA_TCD_CITER_CITER(citer), &(tcd->citer));
+ edma_writew(edma, EDMA_TCD_DOFF_DOFF(doff), &(tcd->doff));
+ edma_writel(edma, EDMA_TCD_DLAST_SGA_DLAST_SGA(dlast_sga), &(tcd->dlast_sga));
+ edma_writew(edma, EDMA_TCD_BITER_BITER(biter), &(tcd->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;
+
+ edma_writew(edma, csr, &(tcd->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 err;
+ }
+ return fsl_desc;
+
+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_readl(fsl_edma, base_addr + EDMA_INTR);
+ if (!intr)
+ return IRQ_NONE;
+
+ for (ch = 0; ch < fsl_edma->n_chans; ch++) {
+ if (intr & (0x1 << ch)) {
+ edma_writeb(fsl_edma, 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_readl(fsl_edma, 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(fsl_edma, 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 struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
+ struct of_dma *ofdma)
+{
+ struct fsl_edma_engine *fsl_edma = ofdma->of_dma_data;
+ struct dma_chan *chan;
+
+ if (dma_spec->args_count != 2)
+ return NULL;
+
+ mutex_lock(&fsl_edma_mutex);
+ list_for_each_entry(chan, &fsl_edma->dma_dev.channels, device_node) {
+ if (chan->client_count)
+ continue;
+ if ((chan->chan_id / DMAMUX_NR) == dma_spec->args[0]) {
+ chan = dma_get_slave_channel(chan);
+ if (chan) {
+ chan->device->privatecnt++;
+ fsl_edma_chan_mux(to_fsl_edma_chan(chan),
+ dma_spec->args[1], true);
+ mutex_unlock(&fsl_edma_mutex);
+ return chan;
+ }
+ }
+ }
+ mutex_unlock(&fsl_edma_mutex);
+ return NULL;
+}
+
+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(fsl_edma, 0x0, fsl_edma->membase + EDMA_TCD_CSR(i));
+ fsl_edma_chan_mux(fsl_chan, 0, false);
+ }
+
+ dma_cap_set(DMA_PRIVATE, fsl_edma->dma_dev.cap_mask);
+ 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(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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