[PATCH 3/3] dma: Add Freescale eDMA engine driver support

Jingchang Lu
2013-08-02T08:48:44Z

Add Freescale enhanced direct memory(eDMA) controller support.
The eDMA controller deploys DMAMUXs routing DMA request sources(slot)
to eDMA channels.
This module can be found on Vybrid and LS-1 SoCs.

Signed-off-by: Alison Wang <b18965@freescale.com>
Signed-off-by: Xiaochun Li <b41219@freescale.com>
Signed-off-by: Jingchang Lu <b35083@freescale.com>
---
.../devicetree/bindings/dma/fsl-vf610-edma.txt | 84 +++
drivers/dma/Kconfig | 10 +
drivers/dma/Makefile | 1 +
drivers/dma/fsl-edma.c | 826 +++++++++++++++++++++
4 files changed, 921 insertions(+)
create mode 100644 Documentation/devicetree/bindings/dma/fsl-vf610-edma.txt
create mode 100644 drivers/dma/fsl-edma.c

diff --git a/Documentation/devicetree/bindings/dma/fsl-vf610-edma.txt b/Documentation/devicetree/bindings/dma/fsl-vf610-edma.txt
new file mode 100644
index 0000000..e6dc5cd
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/fsl-vf610-edma.txt
@@ -0,0 +1,84 @@
+* Freescale enhanced direct memory access(eDMA) Controller
+
+The eDMA engine deploys DMAMUXs routing request sources(slot) to
+eDMA controller channels.
+
+* eDMA Controller
+Required properties:
+- compatible : Should be "fsl,<chip>-edma"
+- reg : Should contain eDMA registers location and length
+- interrupts : Should contain eDMA interrupt
+- interrupt-names : Should be "edma-tx" for tx interrupt and
+ "edma-err" for err interrupt
+- #dma-cells : Must be <2>.
+ The first cell specifies the DMAMUX ID. Specific request source
+ can only be routed by specific DMAMUXs.
+ the second cell specifies the request source(slot) ID.
+ See include/dt-bindings/dma/<soc>-edma.h for all the supported
+ request source IDs.
+- fsl,dma-channels : Number of channels supported by the controller
+- fsl,dma-mux : Phandle of the DMAMUXs deployed by the controller
+
+
+* DMAMUX
+Required properties:
+- reg : Should contain DMAMUX registers location and length
+- fsl,dmamux-id : DMAMUX ID. DMAMUX IDs are unique in each eDMA controller.
+ inside one eDMA controller, specific request source can only be routed by
+ one of its DMAMUXs.
+ However Specific request source may be routed to different eDMA controller,
+ thus all the DMAMUXs sharing a the same request sources have the same ID.
+- clocks : Phandle of the clock used by the DMAMUX
+- clock-names : The clock names
+
+Below is the eDMA controller and DMAMUX association, and DMAMUX IDs assignment
+On Vybrid vf610 SoC, DMAMUX0 and DMAMU3 share the same request source group,
+and DMAMUX1 and DMAMU2 share the same request source group.
+
+eDMA controller DMAMUXs DMAMUX ID
+-------------------------------------------------
+eDMA0 DMAMUX0 0
+ DMAMUX1 1
+
+eDMA1 DMAMUX2 1
+ DMAMUX3 0
+
+Examples:
+
+edma0: edma@40018000 {
+ #dma-cells = <2>;
+ compatible = "fsl,vf610-edma";
+ reg = <0x40018000 0x2000>;
+ interrupts = <0 8 0x04>, <0 9 0x04>;
+ interrupt-names = "edma-tx", "edma-err";
+ fsl,edma-channels = <32>;
+ fsl,edma-mux = <&dmamux0>, <&dmamux1>;
+ };
+
+dmamux0: dmamux@40024000 {
+ reg = <0x40024000 0x1000>;
+ fsl,dmamux-id = <0>;
+ clocks = <&clks VF610_CLK_DMAMUX0>;
+ clock-names = "dmamux";
+};
+
+
+* DMA clients
+DMA client drivers that uses the DMA function must use the format described
+in the dma.txt file, using a three-cell specifier for each channel: a phandle
+plus two integer cells as described above.
+
+Examples:
+
+sai2: sai@40031000 {
+ compatible = "fsl,vf610-sai";
+ reg = <0x40031000 0x1000>;
+ interrupts = <0 86 0x04>;
+ clocks = <&clks VF610_CLK_SAI2>;
+ clock-names = "sai";
+ fsl,sai-dma-events = <21 20>;
+ dma-names = "tx", "rx";
+ dmas = <&edma0 0 DMA_MUXID0_SAI2_TX>,
+ <&edma0 0 DMA_MUXID0_SAI2_RX>;
+ status = "disabled";
+};
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 6825957..f9a6e06 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -300,6 +300,16 @@ config DMA_JZ4740
select DMA_ENGINE
select DMA_VIRTUAL_CHANNELS

+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 managing route
+ between request sources(slot) and 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 5e0f2ef..fcbbac9 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -39,3 +39,4 @@ obj-$(CONFIG_MMP_TDMA) += mmp_tdma.o
obj-$(CONFIG_DMA_OMAP) += omap-dma.o
obj-$(CONFIG_MMP_PDMA) += mmp_pdma.o
obj-$(CONFIG_DMA_JZ4740) += dma-jz4740.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..b3a459f
--- /dev/null
+++ b/drivers/dma/fsl-edma.c
@@ -0,0 +1,826 @@
+/*
+ * drivers/dma/fsl-edma.c
+ *
+ * Copyright 2013 Freescale Semiconductor, Inc.
+ *
+ * Driver for the Freescale eDMA engine with DMAMUXs managing route between
+ * request sources(slot) and eDMA engine channels, this module 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/spinlock.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.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 <linux/dmapool.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_CITER_MASK 0x7FFF
+#define EDMA_TCD_BITER_MASK 0x7FFF
+
+#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)
+
+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_dmamux {
+ void __iomem *membase;
+ struct clk *clk;
+ u32 mux_id;
+};
+
+struct fsl_edma_chan {
+ struct virt_dma_chan vchan;
+ enum dma_status status;
+ struct fsl_edma_engine *edma;
+ struct fsl_edma_dmamux *edmamux;
+ struct fsl_edma_desc *edesc;
+
+ u32 slot_id;
+ 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_irq {
+ int txirq;
+ int errirq;
+};
+
+struct fsl_edma_engine {
+ struct dma_device dma_dev;
+ void __iomem *membase;
+ u32 n_chans;
+ u32 n_muxes;
+ struct fsl_edma_dmamux *edmamux;
+ struct fsl_edma_irq edmairq;
+ struct fsl_edma_chan chans[];
+};
+
+struct fsl_edma_filter_param {
+ int mux_id;
+ int slot_id;
+};
+
+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;
+
+ writeb(EDMA_SEEI_SEEI(ch), addr + EDMA_SEEI);
+ 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;
+
+ writeb(ch, addr + EDMA_CERQ);
+ writeb(EDMA_CEEI_CEEI(ch), addr + EDMA_CEEI);
+}
+
+static
+void fsl_edmamux_config_chan(struct fsl_edma_chan *fsl_chan, unsigned char val)
+{
+ void __iomem *mux_addr = fsl_chan->edmamux->membase;
+ unsigned chans_per_mux, ch;
+
+ chans_per_mux = fsl_chan->edma->n_chans / fsl_chan->edma->n_muxes;
+ ch = fsl_chan->vchan.chan.chan_id % chans_per_mux;
+
+ writeb(val, mux_addr + ch);
+}
+
+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;
+
+ switch (cmd) {
+ case DMA_TERMINATE_ALL:
+ fsl_edma_disable_request(fsl_chan);
+ fsl_chan->edesc = NULL;
+ vchan_free_chan_resources(&fsl_chan->vchan);
+ 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;
+ } else {
+ 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(fsl_chan->fsc.addr_width);
+ return 0;
+ default:
+ return -ENOSYS;
+ }
+}
+
+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);
+
+ if (fsl_chan->status == DMA_ERROR)
+ return DMA_ERROR;
+
+ return dma_cookie_status(chan, cookie, txstate);
+}
+
+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;
+
+ 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(EDMA_TCD_SOFF_SOFF(soff), addr + EDMA_TCD_SOFF(ch));
+ writel(EDMA_TCD_NBYTES_NBYTES(nbytes), addr + EDMA_TCD_NBYTES(ch));
+ writel(EDMA_TCD_SLAST_SLAST(slast), addr + EDMA_TCD_SLAST(ch));
+ writew(EDMA_TCD_CITER_CITER(citer), addr + EDMA_TCD_CITER(ch));
+ writew(EDMA_TCD_BITER_BITER(biter), addr + EDMA_TCD_BITER(ch));
+ writew(EDMA_TCD_DOFF_DOFF(doff), addr + EDMA_TCD_DOFF(ch));
+ writel(EDMA_TCD_DLAST_SGA_DLAST_SGA(dlast_sga),
+ addr + EDMA_TCD_DLAST_SGA(ch));
+ writew(csr, addr + EDMA_TCD_CSR(ch));
+}
+
+static void fill_tcd_params(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)
+{
+ tcd->saddr = src;
+ tcd->attr = attr;
+ tcd->soff = soff;
+ tcd->nbytes = nbytes;
+ tcd->slast = slast;
+ tcd->daddr = dst;
+ tcd->citer = citer;
+ tcd->doff = doff;
+ tcd->dlast_sga = dlast_sga;
+ tcd->biter = biter;
+ tcd->csr = 0;
+ if (major_int)
+ tcd->csr |= EDMA_TCD_CSR_INT_MAJOR;
+
+ if (disable_req)
+ tcd->csr |= EDMA_TCD_CSR_D_REQ;
+
+ if (enable_sg)
+ tcd->csr |= EDMA_TCD_CSR_E_SG;
+}
+
+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 size, i;
+
+ size = sizeof(struct fsl_edma_desc);
+ size += sizeof(struct fsl_edma_sw_tcd) * sg_len;
+ fsl_desc = kzalloc(size, GFP_KERNEL);
+ 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_ATOMIC, &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;
+
+ 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_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;
+
+ 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_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_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_irq_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 = readl(base_addr + EDMA_INTR);
+ if (!intr)
+ return IRQ_NONE;
+
+ for (ch = 0; ch < 32; ch++)
+ if (intr & (0x1 << ch))
+ break;
+
+ writeb(EDMA_CINT_CINT(ch), base_addr + EDMA_CINT);
+
+ fsl_chan = &fsl_edma->chans[ch];
+
+ 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_SUCCESS;
+ } else {
+ vchan_cyclic_callback(&fsl_chan->edesc->vdesc);
+ }
+
+ if (!fsl_chan->edesc)
+ fsl_edma_xfer_desc(fsl_chan);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t fsl_edma_err_handler(int irq, void *dev_id)
+{
+ struct fsl_edma_engine *fsl_edma = dev_id;
+ unsigned long err;
+ int ch;
+
+ err = readl(fsl_edma->membase + EDMA_ERR);
+ if (!err)
+ return IRQ_NONE;
+
+ for (ch = 0; ch < 32; ch++)
+ if (err & (0x1 << ch))
+ break;
+
+ fsl_edma_disable_request(&fsl_edma->chans[ch]);
+ writeb(EDMA_CERR_CERR(ch), fsl_edma->membase + EDMA_CERR);
+ fsl_edma->chans[ch].status = DMA_ERROR;
+
+ return IRQ_HANDLED;
+}
+
+
+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 *fn_param)
+{
+ struct fsl_edma_filter_param *fparam = fn_param;
+ struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
+
+ if (fsl_chan->edmamux->mux_id != fparam->mux_id)
+ return false;
+
+ fsl_chan->slot_id = fparam->slot_id;
+ chan->private = fn_param;
+ return true;
+}
+
+static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
+ struct of_dma *ofdma)
+{
+ dma_cap_mask_t mask;
+ struct fsl_edma_filter_param fparam;
+
+ if (dma_spec->args_count != 2)
+ return NULL;
+
+ fparam.mux_id = dma_spec->args[0];
+ fparam.slot_id = dma_spec->args[1];
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+ return dma_request_channel(mask, fsl_edma_filter_fn, (void *)&fparam);
+}
+
+static int fsl_edma_alloc_chan_resources(struct dma_chan *chan)
+{
+ struct fsl_edma_chan *fsl_chan = to_fsl_edma_chan(chan);
+ struct fsl_edma_filter_param *data = chan->private;
+ unsigned char val;
+
+ val = EDMAMUX_CHCFG_ENBL | EDMAMUX_CHCFG_SOURCE(data->slot_id);
+ fsl_edmamux_config_chan(fsl_chan, val);
+
+ 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);
+
+ fsl_edma_disable_request(fsl_chan);
+ fsl_edmamux_config_chan(fsl_chan, EDMAMUX_CHCFG_DIS);
+ fsl_chan->edesc = NULL;
+ vchan_free_chan_resources(&fsl_chan->vchan);
+ dma_pool_destroy(fsl_chan->tcd_pool);
+ fsl_chan->tcd_pool = NULL;
+}
+
+static int
+fsl_init_edmamux(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct fsl_edma_dmamux *fsl_edmamux;
+ struct device_node *phandle;
+ const void *prop;
+ struct resource res;
+ int len, n_muxes, chans_per_mux, ch_off;
+ int i, j;
+ int ret;
+
+ prop = of_get_property(np, "fsl,dma-mux", &len);
+ if (!prop)
+ return -EINVAL;
+
+ n_muxes = len / sizeof(u32);
+ chans_per_mux = fsl_edma->n_chans / n_muxes;
+ fsl_edmamux = devm_kzalloc(&pdev->dev,
+ sizeof(struct fsl_edma_dmamux) * n_muxes, GFP_KERNEL);
+ if (!fsl_edmamux)
+ return -ENOMEM;
+
+ fsl_edma->n_muxes = 0;
+ fsl_edma->edmamux = fsl_edmamux;
+ for (i = 0; i < n_muxes; i++) {
+ phandle = of_parse_phandle(np, "fsl,dma-mux", i);
+ ret = of_address_to_resource(phandle, 0, &res);
+ if (ret)
+ return ret;
+ fsl_edmamux->membase = devm_ioremap_resource(&pdev->dev, &res);
+ if (IS_ERR(fsl_edmamux->membase))
+ return PTR_ERR(fsl_edmamux->membase);
+
+ fsl_edmamux->clk = of_clk_get(phandle, 0);
+ if (IS_ERR(fsl_edmamux->clk))
+ return PTR_ERR(fsl_edmamux->clk);
+
+ clk_prepare_enable(fsl_edmamux->clk);
+
+ ret = of_property_read_u32_index(phandle, "fsl,dmamux-id", 0,
+ &fsl_edmamux->mux_id);
+ if (ret)
+ return ret;
+
+ ch_off = fsl_edma->n_muxes * chans_per_mux;
+ for (j = 0; j < chans_per_mux; j++)
+ fsl_edma->chans[ch_off + j].edmamux = fsl_edmamux;
+
+ fsl_edmamux++;
+ fsl_edma->n_muxes++;
+ }
+ return 0;
+}
+
+static int
+fsl_edma_init_irq(struct platform_device *pdev, struct fsl_edma_engine *fsl_edma)
+{
+ int ret;
+
+ fsl_edma->edmairq.txirq = platform_get_irq_byname(pdev, "edma-tx");
+ if (fsl_edma->edmairq.txirq < 0)
+ return -EINVAL;
+
+ ret = devm_request_irq(&pdev->dev, fsl_edma->edmairq.txirq,
+ fsl_edma_irq_handler, IRQF_SHARED, "eDMA tx", fsl_edma);
+ if (ret) {
+ dev_err(&pdev->dev, "Can't register eDMA tx IRQ.\n");
+ return ret;
+ }
+
+ fsl_edma->edmairq.errirq = platform_get_irq_byname(pdev, "edma-err");
+ if (fsl_edma->edmairq.errirq < 0)
+ return -EINVAL;
+
+ ret = devm_request_irq(&pdev->dev, fsl_edma->edmairq.errirq,
+ fsl_edma_err_handler, IRQF_SHARED, "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_index(np, "fsl,dma-channels", 0, &chans);
+ if (ret)
+ return -EINVAL;
+
+ 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);
+
+ ret = fsl_init_edmamux(pdev, fsl_edma);
+ if (ret)
+ return ret;
+
+ ret = fsl_edma_init_irq(pdev, fsl_edma);
+ if (ret)
+ return ret;
+
+ 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);
+
+ writew(0x0, fsl_edma->membase + EDMA_TCD_CSR(i));
+ fsl_edmamux_config_chan(fsl_chan, EDMAMUX_CHCFG_DIS);
+ }
+
+ 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 */
+ writel(EDMA_CR_ERGA | EDMA_CR_ERCA, fsl_edma->membase + EDMA_CR);
+
+ return 0;
+}
+
+static int fsl_edma_remove(struct platform_device *pdev)
+{
+ struct fsl_edma_engine *fsl_edma = platform_get_drvdata(pdev);
+ int i;
+
+ dma_async_device_unregister(&fsl_edma->dma_dev);
+
+ for (i = 0; i < fsl_edma->n_muxes; i++) {
+ clk_disable_unprepare(fsl_edma->edmamux[i].clk);
+ clk_put(fsl_edma->edmamux[i].clk);
+ }
+
+ 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,
+};
+
+static int __init fsl_edma_module_init(void)
+{
+ return platform_driver_probe(&fsl_edma_driver, fsl_edma_probe);
+}
+module_init(fsl_edma_module_init);
+
+MODULE_DESCRIPTION("Freescale eDMA engine driver");
+MODULE_LICENSE("GPL v2");
--
1.8.0