--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Actions Semi Owl SoCs DMA driver
+//
+// Copyright (c) 2014 Actions Semi Inc.
+// Author: David Liu <liuwei@actions-semi.com>
+//
+// Copyright (c) 2018 Linaro Ltd.
+// Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmapool.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/slab.h>
+#include "virt-dma.h"
+
+#define OWL_DMA_FRAME_MAX_LENGTH 0xfffff
+
+/* Global DMA Controller Registers */
+#define OWL_DMA_IRQ_PD0 0x00
+#define OWL_DMA_IRQ_PD1 0x04
+#define OWL_DMA_IRQ_PD2 0x08
+#define OWL_DMA_IRQ_PD3 0x0C
+#define OWL_DMA_IRQ_EN0 0x10
+#define OWL_DMA_IRQ_EN1 0x14
+#define OWL_DMA_IRQ_EN2 0x18
+#define OWL_DMA_IRQ_EN3 0x1C
+#define OWL_DMA_SECURE_ACCESS_CTL 0x20
+#define OWL_DMA_NIC_QOS 0x24
+#define OWL_DMA_DBGSEL 0x28
+#define OWL_DMA_IDLE_STAT 0x2C
+
+/* Channel Registers */
+#define OWL_DMA_CHAN_BASE(i) (0x100 + (i) * 0x100)
+#define OWL_DMAX_MODE 0x00
+#define OWL_DMAX_SOURCE 0x04
+#define OWL_DMAX_DESTINATION 0x08
+#define OWL_DMAX_FRAME_LEN 0x0C
+#define OWL_DMAX_FRAME_CNT 0x10
+#define OWL_DMAX_REMAIN_FRAME_CNT 0x14
+#define OWL_DMAX_REMAIN_CNT 0x18
+#define OWL_DMAX_SOURCE_STRIDE 0x1C
+#define OWL_DMAX_DESTINATION_STRIDE 0x20
+#define OWL_DMAX_START 0x24
+#define OWL_DMAX_PAUSE 0x28
+#define OWL_DMAX_CHAINED_CTL 0x2C
+#define OWL_DMAX_CONSTANT 0x30
+#define OWL_DMAX_LINKLIST_CTL 0x34
+#define OWL_DMAX_NEXT_DESCRIPTOR 0x38
+#define OWL_DMAX_CURRENT_DESCRIPTOR_NUM 0x3C
+#define OWL_DMAX_INT_CTL 0x40
+#define OWL_DMAX_INT_STATUS 0x44
+#define OWL_DMAX_CURRENT_SOURCE_POINTER 0x48
+#define OWL_DMAX_CURRENT_DESTINATION_POINTER 0x4C
+
+/* OWL_DMAX_MODE Bits */
+#define OWL_DMA_MODE_TS(x) (((x) & GENMASK(5, 0)) << 0)
+#define OWL_DMA_MODE_ST(x) (((x) & GENMASK(1, 0)) << 8)
+#define OWL_DMA_MODE_ST_DEV OWL_DMA_MODE_ST(0)
+#define OWL_DMA_MODE_ST_DCU OWL_DMA_MODE_ST(2)
+#define OWL_DMA_MODE_ST_SRAM OWL_DMA_MODE_ST(3)
+#define OWL_DMA_MODE_DT(x) (((x) & GENMASK(1, 0)) << 10)
+#define OWL_DMA_MODE_DT_DEV OWL_DMA_MODE_DT(0)
+#define OWL_DMA_MODE_DT_DCU OWL_DMA_MODE_DT(2)
+#define OWL_DMA_MODE_DT_SRAM OWL_DMA_MODE_DT(3)
+#define OWL_DMA_MODE_SAM(x) (((x) & GENMASK(1, 0)) << 16)
+#define OWL_DMA_MODE_SAM_CONST OWL_DMA_MODE_SAM(0)
+#define OWL_DMA_MODE_SAM_INC OWL_DMA_MODE_SAM(1)
+#define OWL_DMA_MODE_SAM_STRIDE OWL_DMA_MODE_SAM(2)
+#define OWL_DMA_MODE_DAM(x) (((x) & GENMASK(1, 0)) << 18)
+#define OWL_DMA_MODE_DAM_CONST OWL_DMA_MODE_DAM(0)
+#define OWL_DMA_MODE_DAM_INC OWL_DMA_MODE_DAM(1)
+#define OWL_DMA_MODE_DAM_STRIDE OWL_DMA_MODE_DAM(2)
+#define OWL_DMA_MODE_PW(x) (((x) & GENMASK(2, 0)) << 20)
+#define OWL_DMA_MODE_CB BIT(23)
+#define OWL_DMA_MODE_NDDBW(x) (((x) & 0x1) << 28)
+#define OWL_DMA_MODE_NDDBW_32BIT OWL_DMA_MODE_NDDBW(0)
+#define OWL_DMA_MODE_NDDBW_8BIT OWL_DMA_MODE_NDDBW(1)
+#define OWL_DMA_MODE_CFE BIT(29)
+#define OWL_DMA_MODE_LME BIT(30)
+#define OWL_DMA_MODE_CME BIT(31)
+
+/* OWL_DMAX_LINKLIST_CTL Bits */
+#define OWL_DMA_LLC_SAV(x) (((x) & GENMASK(1, 0)) << 8)
+#define OWL_DMA_LLC_SAV_INC OWL_DMA_LLC_SAV(0)
+#define OWL_DMA_LLC_SAV_LOAD_NEXT OWL_DMA_LLC_SAV(1)
+#define OWL_DMA_LLC_SAV_LOAD_PREV OWL_DMA_LLC_SAV(2)
+#define OWL_DMA_LLC_DAV(x) (((x) & GENMASK(1, 0)) << 10)
+#define OWL_DMA_LLC_DAV_INC OWL_DMA_LLC_DAV(0)
+#define OWL_DMA_LLC_DAV_LOAD_NEXT OWL_DMA_LLC_DAV(1)
+#define OWL_DMA_LLC_DAV_LOAD_PREV OWL_DMA_LLC_DAV(2)
+#define OWL_DMA_LLC_SUSPEND BIT(16)
+
+/* OWL_DMAX_INT_CTL Bits */
+#define OWL_DMA_INTCTL_BLOCK BIT(0)
+#define OWL_DMA_INTCTL_SUPER_BLOCK BIT(1)
+#define OWL_DMA_INTCTL_FRAME BIT(2)
+#define OWL_DMA_INTCTL_HALF_FRAME BIT(3)
+#define OWL_DMA_INTCTL_LAST_FRAME BIT(4)
+
+/* OWL_DMAX_INT_STATUS Bits */
+#define OWL_DMA_INTSTAT_BLOCK BIT(0)
+#define OWL_DMA_INTSTAT_SUPER_BLOCK BIT(1)
+#define OWL_DMA_INTSTAT_FRAME BIT(2)
+#define OWL_DMA_INTSTAT_HALF_FRAME BIT(3)
+#define OWL_DMA_INTSTAT_LAST_FRAME BIT(4)
+
+/* Pack shift and newshift in a single word */
+#define BIT_FIELD(val, width, shift, newshift) \
+ ((((val) >> (shift)) & ((BIT(width)) - 1)) << (newshift))
+
+/**
+ * struct owl_dma_lli_hw - Hardware link list for dma transfer
+ * @next_lli: physical address of the next link list
+ * @saddr: source physical address
+ * @daddr: destination physical address
+ * @flen: frame length
+ * @fcnt: frame count
+ * @src_stride: source stride
+ * @dst_stride: destination stride
+ * @ctrla: dma_mode and linklist ctrl config
+ * @ctrlb: interrupt config
+ * @const_num: data for constant fill
+ */
+struct owl_dma_lli_hw {
+ u32 next_lli;
+ u32 saddr;
+ u32 daddr;
+ u32 flen:20;
+ u32 fcnt:12;
+ u32 src_stride;
+ u32 dst_stride;
+ u32 ctrla;
+ u32 ctrlb;
+ u32 const_num;
+};
+
+/**
+ * struct owl_dma_lli - Link list for dma transfer
+ * @hw: hardware link list
+ * @phys: physical address of hardware link list
+ * @node: node for txd's lli_list
+ */
+struct owl_dma_lli {
+ struct owl_dma_lli_hw hw;
+ dma_addr_t phys;
+ struct list_head node;
+};
+
+/**
+ * struct owl_dma_txd - Wrapper for struct dma_async_tx_descriptor
+ * @vd: virtual DMA descriptor
+ * @lli_list: link list of lli nodes
+ */
+struct owl_dma_txd {
+ struct virt_dma_desc vd;
+ struct list_head lli_list;
+};
+
+/**
+ * struct owl_dma_pchan - Holder for the physical channels
+ * @id: physical index to this channel
+ * @base: virtual memory base for the dma channel
+ * @vchan: the virtual channel currently being served by this physical channel
+ * @lock: a lock to use when altering an instance of this struct
+ */
+struct owl_dma_pchan {
+ u32 id;
+ void __iomem *base;
+ struct owl_dma_vchan *vchan;
+ spinlock_t lock;
+};
+
+/**
+ * struct owl_dma_pchan - Wrapper for DMA ENGINE channel
+ * @vc: wrappped virtual channel
+ * @pchan: the physical channel utilized by this channel
+ * @txd: active transaction on this channel
+ */
+struct owl_dma_vchan {
+ struct virt_dma_chan vc;
+ struct owl_dma_pchan *pchan;
+ struct owl_dma_txd *txd;
+};
+
+/**
+ * struct owl_dma - Holder for the Owl DMA controller
+ * @dma: dma engine for this instance
+ * @base: virtual memory base for the DMA controller
+ * @clk: clock for the DMA controller
+ * @lock: a lock to use when change DMA controller global register
+ * @lli_pool: a pool for the LLI descriptors
+ * @nr_pchans: the number of physical channels
+ * @pchans: array of data for the physical channels
+ * @nr_vchans: the number of physical channels
+ * @vchans: array of data for the physical channels
+ */
+struct owl_dma {
+ struct dma_device dma;
+ void __iomem *base;
+ struct clk *clk;
+ spinlock_t lock;
+ struct dma_pool *lli_pool;
+ int irq;
+
+ unsigned int nr_pchans;
+ struct owl_dma_pchan *pchans;
+
+ unsigned int nr_vchans;
+ struct owl_dma_vchan *vchans;
+};
+
+static void pchan_update(struct owl_dma_pchan *pchan, u32 reg,
+ u32 val, bool state)
+{
+ u32 regval;
+
+ regval = readl(pchan->base + reg);
+
+ if (state)
+ regval |= val;
+ else
+ regval &= ~val;
+
+ writel(val, pchan->base + reg);
+}
+
+static void pchan_writel(struct owl_dma_pchan *pchan, u32 reg, u32 data)
+{
+ writel(data, pchan->base + reg);
+}
+
+static u32 pchan_readl(struct owl_dma_pchan *pchan, u32 reg)
+{
+ return readl(pchan->base + reg);
+}
+
+static void dma_update(struct owl_dma *od, u32 reg, u32 val, bool state)
+{
+ u32 regval;
+
+ regval = readl(od->base + reg);
+
+ if (state)
+ regval |= val;
+ else
+ regval &= ~val;
+
+ writel(val, od->base + reg);
+}
+
+static void dma_writel(struct owl_dma *od, u32 reg, u32 data)
+{
+ writel(data, od->base + reg);
+}
+
+static u32 dma_readl(struct owl_dma *od, u32 reg)
+{
+ return readl(od->base + reg);
+}
+
+static inline struct owl_dma *to_owl_dma(struct dma_device *dd)
+{
+ return container_of(dd, struct owl_dma, dma);
+}
+
+static struct device *chan2dev(struct dma_chan *chan)
+{
+ return &chan->dev->device;
+}
+
+static inline struct owl_dma_vchan *to_owl_vchan(struct dma_chan *chan)
+{
+ return container_of(chan, struct owl_dma_vchan, vc.chan);
+}
+
+static inline struct owl_dma_txd *to_owl_txd(struct dma_async_tx_descriptor *tx)
+{
+ return container_of(tx, struct owl_dma_txd, vd.tx);
+}
+
+static inline u32 llc_hw_ctrla(u32 mode, u32 llc_ctl)
+{
+ u32 ctl;
+
+ ctl = BIT_FIELD(mode, 4, 28, 28) |
+ BIT_FIELD(mode, 8, 16, 20) |
+ BIT_FIELD(mode, 4, 8, 16) |
+ BIT_FIELD(mode, 6, 0, 10) |
+ BIT_FIELD(llc_ctl, 2, 10, 8) |
+ BIT_FIELD(llc_ctl, 2, 8, 6);
+
+ return ctl;
+}
+
+static inline u32 llc_hw_ctrlb(u32 int_ctl)
+{
+ u32 ctl;
+
+ ctl = BIT_FIELD(int_ctl, 7, 0, 18);
+
+ return ctl;
+}
+
+static void owl_dma_free_lli(struct owl_dma *od,
+ struct owl_dma_lli *lli)
+{
+ list_del(&lli->node);
+ dma_pool_free(od->lli_pool, lli, lli->phys);
+}
+
+static struct owl_dma_lli *owl_dma_alloc_lli(struct owl_dma *od)
+{
+ struct owl_dma_lli *lli;
+ dma_addr_t phys;
+
+ lli = dma_pool_alloc(od->lli_pool, GFP_NOWAIT, &phys);
+ if (!lli)
+ return NULL;
+
+ INIT_LIST_HEAD(&lli->node);
+ lli->phys = phys;
+
+ return lli;
+}
+
+static struct owl_dma_lli *owl_dma_add_lli(struct owl_dma_txd *txd,
+ struct owl_dma_lli *prev,
+ struct owl_dma_lli *next)
+{
+ list_add_tail(&next->node, &txd->lli_list);
+
+ if (prev) {
+ prev->hw.next_lli = next->phys;
+ prev->hw.ctrla |= llc_hw_ctrla(OWL_DMA_MODE_LME, 0);
+ }
+
+ return next;
+}
+
+static inline int owl_dma_cfg_lli(struct owl_dma_vchan *vchan,
+ struct owl_dma_lli *lli,
+ dma_addr_t src, dma_addr_t dst,
+ u32 len, enum dma_transfer_direction dir)
+{
+ struct owl_dma_lli_hw *hw = &lli->hw;
+ u32 mode;
+
+ mode = OWL_DMA_MODE_PW(0);
+
+ switch (dir) {
+ case DMA_MEM_TO_MEM:
+ mode |= OWL_DMA_MODE_TS(0) | OWL_DMA_MODE_ST_DCU |
+ OWL_DMA_MODE_DT_DCU | OWL_DMA_MODE_SAM_INC |
+ OWL_DMA_MODE_DAM_INC;
+
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ hw->next_lli = 0; /* One link list by default */
+ hw->saddr = src;
+ hw->daddr = dst;
+
+ hw->fcnt = 1; /* Frame count fixed as 1 */
+ hw->flen = len; /* Max frame length is 1MB */
+ hw->src_stride = 0;
+ hw->dst_stride = 0;
+ hw->ctrla = llc_hw_ctrla(mode,
+ OWL_DMA_LLC_SAV_LOAD_NEXT |
+ OWL_DMA_LLC_DAV_LOAD_NEXT);
+
+ hw->ctrlb = llc_hw_ctrlb(OWL_DMA_INTCTL_SUPER_BLOCK);
+
+ return 0;
+}
+
+static struct owl_dma_pchan *owl_dma_get_pchan(struct owl_dma *od,
+ struct owl_dma_vchan *vchan)
+{
+ struct owl_dma_pchan *pchan = NULL;
+ unsigned long flags;
+ int i;
+
+ for (i = 0; i < od->nr_pchans; i++) {
+ pchan = &od->pchans[i];
+
+ spin_lock_irqsave(&pchan->lock, flags);
+ if (!pchan->vchan) {
+ pchan->vchan = vchan;
+ spin_unlock_irqrestore(&pchan->lock, flags);
+ break;
+ }
+
+ spin_unlock_irqrestore(&pchan->lock, flags);
+ }
+
+ return pchan;
+}
+
+static int owl_dma_pchan_busy(struct owl_dma *od, struct owl_dma_pchan *pchan)
+{
+ unsigned int val;
+
+ val = dma_readl(od, OWL_DMA_IDLE_STAT);
+
+ return !(val & (1 << pchan->id));
+}
+
+static void owl_dma_terminate_pchan(struct owl_dma *od,
+ struct owl_dma_pchan *pchan)
+{
+ unsigned long flags;
+ u32 irq_pd;
+
+ pchan_writel(pchan, OWL_DMAX_START, 0);
+ pchan_update(pchan, OWL_DMAX_INT_STATUS, 0xff, false);
+
+ spin_lock_irqsave(&od->lock, flags);
+ dma_update(od, OWL_DMA_IRQ_EN0, (1 << pchan->id), false);
+
+ irq_pd = dma_readl(od, OWL_DMA_IRQ_PD0);
+ if (irq_pd & (1 << pchan->id)) {
+ dev_warn(od->dma.dev,
+ "terminating pchan %d that still has pending irq\n",
+ pchan->id);
+ dma_writel(od, OWL_DMA_IRQ_PD0, (1 << pchan->id));
+ }
+
+ pchan->vchan = NULL;
+
+ spin_unlock_irqrestore(&od->lock, flags);
+}
+
+static int owl_dma_start_next_txd(struct owl_dma_vchan *vchan)
+{
+ struct owl_dma *od = to_owl_dma(vchan->vc.chan.device);
+ struct virt_dma_desc *vd = vchan_next_desc(&vchan->vc);
+ struct owl_dma_pchan *pchan = vchan->pchan;
+ struct owl_dma_txd *txd = to_owl_txd(&vd->tx);
+ struct owl_dma_lli *lli;
+ unsigned long flags;
+ u32 int_ctl;
+
+ list_del(&vd->node);
+
+ vchan->txd = txd;
+
+ /* Wait for channel inactive */
+ while (owl_dma_pchan_busy(od, pchan))
+ cpu_relax();
+
+ lli = list_first_entry(&txd->lli_list,
+ struct owl_dma_lli, node);
+
+ int_ctl = OWL_DMA_INTCTL_SUPER_BLOCK;
+
+ pchan_writel(pchan, OWL_DMAX_MODE, OWL_DMA_MODE_LME);
+ pchan_writel(pchan, OWL_DMAX_LINKLIST_CTL,
+ OWL_DMA_LLC_SAV_LOAD_NEXT | OWL_DMA_LLC_DAV_LOAD_NEXT);
+ pchan_writel(pchan, OWL_DMAX_NEXT_DESCRIPTOR, lli->phys);
+ pchan_writel(pchan, OWL_DMAX_INT_CTL, int_ctl);
+
+ /* Clear IRQ status for this pchan */
+ pchan_update(pchan, OWL_DMAX_INT_STATUS, 0xff, false);
+
+ spin_lock_irqsave(&od->lock, flags);
+
+ dma_update(od, OWL_DMA_IRQ_EN0, (1 << pchan->id), true);
+
+ spin_unlock_irqrestore(&od->lock, flags);
+
+ dev_dbg(chan2dev(&vchan->vc.chan), "starting pchan %d\n", pchan->id);
+
+ /* Start DMA transfer for this pchan */
+ pchan_writel(pchan, OWL_DMAX_START, 0x1);
+
+ return 0;
+}
+
+static void owl_dma_phy_free(struct owl_dma *od, struct owl_dma_vchan *vchan)
+{
+ /* Ensure that the physical channel is stopped */
+ owl_dma_terminate_pchan(od, vchan->pchan);
+
+ vchan->pchan = NULL;
+}
+
+static irqreturn_t owl_dma_interrupt(int irq, void *dev_id)
+{
+ struct owl_dma *od = dev_id;
+ struct owl_dma_vchan *vchan;
+ struct owl_dma_pchan *pchan;
+ unsigned long pending;
+ int i;
+ unsigned int global_irq_pending, chan_irq_pending;
+
+ spin_lock(&od->lock);
+
+ pending = dma_readl(od, OWL_DMA_IRQ_PD0);
+
+ /* Clear IRQ status for each pchan */
+ for_each_set_bit(i, &pending, od->nr_pchans) {
+ pchan = &od->pchans[i];
+ pchan_update(pchan, OWL_DMAX_INT_STATUS, 0xff, false);
+ }
+
+ /* Clear pending IRQ */
+ dma_writel(od, OWL_DMA_IRQ_PD0, pending);
+
+ /* Check missed pending IRQ */
+ for (i = 0; i < od->nr_pchans; i++) {
+ pchan = &od->pchans[i];
+ chan_irq_pending = pchan_readl(pchan, OWL_DMAX_INT_CTL) &
+ pchan_readl(pchan, OWL_DMAX_INT_STATUS);
+
+ /* Dummy read to ensure OWL_DMA_IRQ_PD0 value is updated */
+ dma_readl(od, OWL_DMA_IRQ_PD0);
+
+ global_irq_pending = dma_readl(od, OWL_DMA_IRQ_PD0);
+
+ if (chan_irq_pending && !(global_irq_pending & BIT(i))) {
+ dev_dbg(od->dma.dev,
+ "global and channel IRQ pending match err\n");
+
+ /* Clear IRQ status for this pchan */
+ pchan_update(pchan, OWL_DMAX_INT_STATUS,
+ 0xff, false);
+
+ /* Update global IRQ pending */
+ pending |= BIT(i);
+ }
+ }
+
+ spin_unlock(&od->lock);
+
+ for_each_set_bit(i, &pending, od->nr_pchans) {
+ struct owl_dma_txd *txd;
+
+ pchan = &od->pchans[i];
+
+ vchan = pchan->vchan;
+ if (!vchan) {
+ dev_warn(od->dma.dev, "no vchan attached on pchan %d\n",
+ pchan->id);
+ continue;
+ }
+
+ spin_lock(&vchan->vc.lock);
+
+ txd = vchan->txd;
+ if (txd) {
+ vchan->txd = NULL;
+
+ vchan_cookie_complete(&txd->vd);
+
+ /*
+ * Start the next descriptor (if any),
+ * otherwise free this channel.
+ */
+ if (vchan_next_desc(&vchan->vc))
+ owl_dma_start_next_txd(vchan);
+ else
+ owl_dma_phy_free(od, vchan);
+ }
+
+ spin_unlock(&vchan->vc.lock);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static void owl_dma_free_txd(struct owl_dma *od, struct owl_dma_txd *txd)
+{
+ struct owl_dma_lli *lli, *_lli;
+
+ if (unlikely(!txd))
+ return;
+
+ list_for_each_entry_safe(lli, _lli, &txd->lli_list, node)
+ owl_dma_free_lli(od, lli);
+
+ kfree(txd);
+}
+
+static void owl_dma_desc_free(struct virt_dma_desc *vd)
+{
+ struct owl_dma *od = to_owl_dma(vd->tx.chan->device);
+ struct owl_dma_txd *txd = to_owl_txd(&vd->tx);
+
+ owl_dma_free_txd(od, txd);
+}
+
+static int owl_dma_terminate_all(struct dma_chan *chan)
+{
+ struct owl_dma *od = to_owl_dma(chan->device);
+ struct owl_dma_vchan *vchan = to_owl_vchan(chan);
+ unsigned long flags;
+ LIST_HEAD(head);
+
+ spin_lock_irqsave(&vchan->vc.lock, flags);
+
+ if (vchan->pchan)
+ owl_dma_phy_free(od, vchan);
+
+ if (vchan->txd) {
+ owl_dma_desc_free(&vchan->txd->vd);
+ vchan->txd = NULL;
+ }
+
+ vchan_get_all_descriptors(&vchan->vc, &head);
+ vchan_dma_desc_free_list(&vchan->vc, &head);
+
+ spin_unlock_irqrestore(&vchan->vc.lock, flags);
+
+ return 0;
+}
+
+static u32 owl_dma_getbytes_chan(struct owl_dma_vchan *vchan)
+{
+ struct owl_dma_pchan *pchan;
+ struct owl_dma_txd *txd;
+ struct owl_dma_lli *lli;
+ unsigned int next_lli_phy;
+ size_t bytes;
+
+ pchan = vchan->pchan;
+ txd = vchan->txd;
+
+ if (!pchan || !txd)
+ return 0;
+
+ /* Get remain count of current node in link list */
+ bytes = pchan_readl(pchan, OWL_DMAX_REMAIN_CNT);
+
+ /* Loop through the preceding nodes to get total remaining bytes */
+ if (pchan_readl(pchan, OWL_DMAX_MODE) & OWL_DMA_MODE_LME) {
+ next_lli_phy = pchan_readl(pchan, OWL_DMAX_NEXT_DESCRIPTOR);
+ list_for_each_entry(lli, &txd->lli_list, node) {
+ /* Start from the next active node */
+ if (lli->phys == next_lli_phy) {
+ list_for_each_entry(lli, &txd->lli_list, node)
+ bytes += lli->hw.flen;
+ break;
+ }
+ }
+ }
+
+ return bytes;
+}
+
+static enum dma_status owl_dma_tx_status(struct dma_chan *chan,
+ dma_cookie_t cookie,
+ struct dma_tx_state *state)
+{
+ struct owl_dma_vchan *vchan = to_owl_vchan(chan);
+ struct owl_dma_lli *lli;
+ struct virt_dma_desc *vd;
+ struct owl_dma_txd *txd;
+ enum dma_status ret;
+ unsigned long flags;
+ size_t bytes = 0;
+
+ ret = dma_cookie_status(chan, cookie, state);
+ if (ret == DMA_COMPLETE || !state)
+ return ret;
+
+ spin_lock_irqsave(&vchan->vc.lock, flags);
+
+ vd = vchan_find_desc(&vchan->vc, cookie);
+ if (vd) {
+ txd = to_owl_txd(&vd->tx);
+ list_for_each_entry(lli, &txd->lli_list, node)
+ bytes += lli->hw.flen;
+ } else {
+ bytes = owl_dma_getbytes_chan(vchan);
+ }
+
+ spin_unlock_irqrestore(&vchan->vc.lock, flags);
+
+ dma_set_residue(state, bytes);
+
+ return ret;
+}
+
+static void owl_dma_phy_alloc_and_start(struct owl_dma_vchan *vchan)
+{
+ struct owl_dma *od = to_owl_dma(vchan->vc.chan.device);
+ struct owl_dma_pchan *pchan;
+
+ pchan = owl_dma_get_pchan(od, vchan);
+ if (!pchan)
+ return;
+
+ dev_dbg(od->dma.dev, "allocated pchan %d\n", pchan->id);
+
+ vchan->pchan = pchan;
+ owl_dma_start_next_txd(vchan);
+}
+
+static void owl_dma_issue_pending(struct dma_chan *chan)
+{
+ struct owl_dma_vchan *vchan = to_owl_vchan(chan);
+ unsigned long flags;
+
+ spin_lock_irqsave(&vchan->vc.lock, flags);
+ if (vchan_issue_pending(&vchan->vc)) {
+ if (!vchan->pchan)
+ owl_dma_phy_alloc_and_start(vchan);
+ }
+ spin_unlock_irqrestore(&vchan->vc.lock, flags);
+}
+
+static struct dma_async_tx_descriptor
+ *owl_dma_prep_memcpy(struct dma_chan *chan,
+ dma_addr_t dst, dma_addr_t src,
+ size_t len, unsigned long flags)
+{
+ struct owl_dma *od = to_owl_dma(chan->device);
+ struct owl_dma_vchan *vchan = to_owl_vchan(chan);
+ struct owl_dma_txd *txd;
+ struct owl_dma_lli *lli, *prev = NULL;
+ size_t offset, bytes;
+ int ret;
+
+ if (!len)
+ return NULL;
+
+ txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
+ if (!txd)
+ return NULL;
+
+ INIT_LIST_HEAD(&txd->lli_list);
+
+ /* Process the transfer as frame by frame */
+ for (offset = 0; offset < len; offset += bytes) {
+ lli = owl_dma_alloc_lli(od);
+ if (!lli) {
+ dev_warn(chan2dev(chan), "failed to allocate lli\n");
+ goto err_txd_free;
+ }
+
+ bytes = min_t(size_t, (len - offset), OWL_DMA_FRAME_MAX_LENGTH);
+
+ ret = owl_dma_cfg_lli(vchan, lli, src + offset, dst + offset,
+ bytes, DMA_MEM_TO_MEM);
+ if (ret) {
+ dev_warn(chan2dev(chan), "failed to config lli\n");
+ goto err_txd_free;
+ }
+
+ prev = owl_dma_add_lli(txd, prev, lli);
+ }
+
+ return vchan_tx_prep(&vchan->vc, &txd->vd, flags);
+
+err_txd_free:
+ owl_dma_free_txd(od, txd);
+ return NULL;
+}
+
+static void owl_dma_free_chan_resources(struct dma_chan *chan)
+{
+ struct owl_dma_vchan *vchan = to_owl_vchan(chan);
+
+ /* Ensure all queued descriptors are freed */
+ vchan_free_chan_resources(&vchan->vc);
+}
+
+static inline void owl_dma_free(struct owl_dma *od)
+{
+ struct owl_dma_vchan *vchan = NULL;
+ struct owl_dma_vchan *next;
+
+ list_for_each_entry_safe(vchan,
+ next, &od->dma.channels, vc.chan.device_node) {
+ list_del(&vchan->vc.chan.device_node);
+ tasklet_kill(&vchan->vc.task);
+ }
+}
+
+static int owl_dma_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct owl_dma *od;
+ struct resource *res;
+ int ret, i, nr_channels, nr_requests;
+
+ od = devm_kzalloc(&pdev->dev, sizeof(*od), GFP_KERNEL);
+ if (!od)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -EINVAL;
+
+ od->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(od->base))
+ return PTR_ERR(od->base);
+
+ ret = of_property_read_u32(np, "dma-channels", &nr_channels);
+ if (ret) {
+ dev_err(&pdev->dev, "can't get dma-channels\n");
+ return ret;
+ }
+
+ ret = of_property_read_u32(np, "dma-requests", &nr_requests);
+ if (ret) {
+ dev_err(&pdev->dev, "can't get dma-requests\n");
+ return ret;
+ }
+
+ dev_info(&pdev->dev, "dma-channels %d, dma-requests %d\n",
+ nr_channels, nr_requests);
+
+ od->nr_pchans = nr_channels;
+ od->nr_vchans = nr_requests;
+
+ pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+
+ platform_set_drvdata(pdev, od);
+ spin_lock_init(&od->lock);
+
+ dma_cap_set(DMA_MEMCPY, od->dma.cap_mask);
+
+ od->dma.dev = &pdev->dev;
+ od->dma.device_free_chan_resources = owl_dma_free_chan_resources;
+ od->dma.device_tx_status = owl_dma_tx_status;
+ od->dma.device_issue_pending = owl_dma_issue_pending;
+ od->dma.device_prep_dma_memcpy = owl_dma_prep_memcpy;
+ od->dma.device_terminate_all = owl_dma_terminate_all;
+ od->dma.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
+ od->dma.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
+ od->dma.directions = BIT(DMA_MEM_TO_MEM);
+ od->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
+
+ INIT_LIST_HEAD(&od->dma.channels);
+
+ od->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(od->clk)) {
+ dev_err(&pdev->dev, "unable to get clock\n");
+ return PTR_ERR(od->clk);
+ }
+
+ /*
+ * Eventhough the DMA controller is capable of generating 4
+ * IRQ's for DMA priority feature, we only use 1 IRQ for
+ * simplification.
+ */
+ od->irq = platform_get_irq(pdev, 0);
+ ret = devm_request_irq(&pdev->dev, od->irq, owl_dma_interrupt, 0,
+ dev_name(&pdev->dev), od);
+ if (ret) {
+ dev_err(&pdev->dev, "unable to request IRQ\n");
+ return ret;
+ }
+
+ /* Init physical channel */
+ od->pchans = devm_kcalloc(&pdev->dev, od->nr_pchans,
+ sizeof(struct owl_dma_pchan), GFP_KERNEL);
+ if (!od->pchans)
+ return -ENOMEM;
+
+ for (i = 0; i < od->nr_pchans; i++) {
+ struct owl_dma_pchan *pchan = &od->pchans[i];
+
+ pchan->id = i;
+ pchan->base = od->base + OWL_DMA_CHAN_BASE(i);
+ }
+
+ /* Init virtual channel */
+ od->vchans = devm_kcalloc(&pdev->dev, od->nr_vchans,
+ sizeof(struct owl_dma_vchan), GFP_KERNEL);
+ if (!od->vchans)
+ return -ENOMEM;
+
+ for (i = 0; i < od->nr_vchans; i++) {
+ struct owl_dma_vchan *vchan = &od->vchans[i];
+
+ vchan->vc.desc_free = owl_dma_desc_free;
+ vchan_init(&vchan->vc, &od->dma);
+ }
+
+ /* Create a pool of consistent memory blocks for hardware descriptors */
+ od->lli_pool = dma_pool_create(dev_name(od->dma.dev), od->dma.dev,
+ sizeof(struct owl_dma_lli),
+ __alignof__(struct owl_dma_lli),
+ 0);
+ if (!od->lli_pool) {
+ dev_err(&pdev->dev, "unable to allocate DMA descriptor pool\n");
+ return -ENOMEM;
+ }
+
+ clk_prepare_enable(od->clk);
+
+ ret = dma_async_device_register(&od->dma);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to register DMA engine device\n");
+ goto err_pool_free;
+ }
+
+ return 0;
+
+err_pool_free:
+ clk_disable_unprepare(od->clk);
+ dma_pool_destroy(od->lli_pool);
+
+ return ret;
+}
+
+static int owl_dma_remove(struct platform_device *pdev)
+{
+ struct owl_dma *od = platform_get_drvdata(pdev);
+
+ dma_async_device_unregister(&od->dma);
+
+ /* Mask all interrupts for this execution environment */
+ dma_writel(od, OWL_DMA_IRQ_EN0, 0x0);
+
+ /* Make sure we won't have any further interrupts */
+ devm_free_irq(od->dma.dev, od->irq, od);
+
+ owl_dma_free(od);
+
+ clk_disable_unprepare(od->clk);
+
+ return 0;
+}
+
+static const struct of_device_id owl_dma_match[] = {
+ { .compatible = "actions,s900-dma", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, owl_dma_match);
+
+static struct platform_driver owl_dma_driver = {
+ .probe = owl_dma_probe,
+ .remove = owl_dma_remove,
+ .driver = {
+ .name = "dma-owl",
+ .of_match_table = of_match_ptr(owl_dma_match),
+ },
+};
+
+static int owl_dma_init(void)
+{
+ return platform_driver_register(&owl_dma_driver);
+}
+subsys_initcall(owl_dma_init);
+
+static void __exit owl_dma_exit(void)
+{
+ platform_driver_unregister(&owl_dma_driver);
+}
+module_exit(owl_dma_exit);
+
+MODULE_AUTHOR("David Liu <liuwei@actions-semi.com>");
+MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
+MODULE_DESCRIPTION("Actions Semi Owl SoCs DMA driver");
+MODULE_LICENSE("GPL");
projects / linux-2.6-microblaze.git / commitdiff