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-rw-r--r--drivers/dma/at_xdmac.c2162
1 files changed, 2162 insertions, 0 deletions
diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
new file mode 100644
index 000000000..861be862a
--- /dev/null
+++ b/drivers/dma/at_xdmac.c
@@ -0,0 +1,2162 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for the Atmel Extensible DMA Controller (aka XDMAC on AT91 systems)
+ *
+ * Copyright (C) 2014 Atmel Corporation
+ *
+ * Author: Ludovic Desroches <ludovic.desroches@atmel.com>
+ */
+
+#include <asm/barrier.h>
+#include <dt-bindings/dma/at91.h>
+#include <linux/clk.h>
+#include <linux/dmaengine.h>
+#include <linux/dmapool.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of_dma.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+
+#include "dmaengine.h"
+
+/* Global registers */
+#define AT_XDMAC_GTYPE 0x00 /* Global Type Register */
+#define AT_XDMAC_NB_CH(i) (((i) & 0x1F) + 1) /* Number of Channels Minus One */
+#define AT_XDMAC_FIFO_SZ(i) (((i) >> 5) & 0x7FF) /* Number of Bytes */
+#define AT_XDMAC_NB_REQ(i) ((((i) >> 16) & 0x3F) + 1) /* Number of Peripheral Requests Minus One */
+#define AT_XDMAC_GCFG 0x04 /* Global Configuration Register */
+#define AT_XDMAC_GWAC 0x08 /* Global Weighted Arbiter Configuration Register */
+#define AT_XDMAC_GIE 0x0C /* Global Interrupt Enable Register */
+#define AT_XDMAC_GID 0x10 /* Global Interrupt Disable Register */
+#define AT_XDMAC_GIM 0x14 /* Global Interrupt Mask Register */
+#define AT_XDMAC_GIS 0x18 /* Global Interrupt Status Register */
+#define AT_XDMAC_GE 0x1C /* Global Channel Enable Register */
+#define AT_XDMAC_GD 0x20 /* Global Channel Disable Register */
+#define AT_XDMAC_GS 0x24 /* Global Channel Status Register */
+#define AT_XDMAC_GRS 0x28 /* Global Channel Read Suspend Register */
+#define AT_XDMAC_GWS 0x2C /* Global Write Suspend Register */
+#define AT_XDMAC_GRWS 0x30 /* Global Channel Read Write Suspend Register */
+#define AT_XDMAC_GRWR 0x34 /* Global Channel Read Write Resume Register */
+#define AT_XDMAC_GSWR 0x38 /* Global Channel Software Request Register */
+#define AT_XDMAC_GSWS 0x3C /* Global channel Software Request Status Register */
+#define AT_XDMAC_GSWF 0x40 /* Global Channel Software Flush Request Register */
+#define AT_XDMAC_VERSION 0xFFC /* XDMAC Version Register */
+
+/* Channel relative registers offsets */
+#define AT_XDMAC_CIE 0x00 /* Channel Interrupt Enable Register */
+#define AT_XDMAC_CIE_BIE BIT(0) /* End of Block Interrupt Enable Bit */
+#define AT_XDMAC_CIE_LIE BIT(1) /* End of Linked List Interrupt Enable Bit */
+#define AT_XDMAC_CIE_DIE BIT(2) /* End of Disable Interrupt Enable Bit */
+#define AT_XDMAC_CIE_FIE BIT(3) /* End of Flush Interrupt Enable Bit */
+#define AT_XDMAC_CIE_RBEIE BIT(4) /* Read Bus Error Interrupt Enable Bit */
+#define AT_XDMAC_CIE_WBEIE BIT(5) /* Write Bus Error Interrupt Enable Bit */
+#define AT_XDMAC_CIE_ROIE BIT(6) /* Request Overflow Interrupt Enable Bit */
+#define AT_XDMAC_CID 0x04 /* Channel Interrupt Disable Register */
+#define AT_XDMAC_CID_BID BIT(0) /* End of Block Interrupt Disable Bit */
+#define AT_XDMAC_CID_LID BIT(1) /* End of Linked List Interrupt Disable Bit */
+#define AT_XDMAC_CID_DID BIT(2) /* End of Disable Interrupt Disable Bit */
+#define AT_XDMAC_CID_FID BIT(3) /* End of Flush Interrupt Disable Bit */
+#define AT_XDMAC_CID_RBEID BIT(4) /* Read Bus Error Interrupt Disable Bit */
+#define AT_XDMAC_CID_WBEID BIT(5) /* Write Bus Error Interrupt Disable Bit */
+#define AT_XDMAC_CID_ROID BIT(6) /* Request Overflow Interrupt Disable Bit */
+#define AT_XDMAC_CIM 0x08 /* Channel Interrupt Mask Register */
+#define AT_XDMAC_CIM_BIM BIT(0) /* End of Block Interrupt Mask Bit */
+#define AT_XDMAC_CIM_LIM BIT(1) /* End of Linked List Interrupt Mask Bit */
+#define AT_XDMAC_CIM_DIM BIT(2) /* End of Disable Interrupt Mask Bit */
+#define AT_XDMAC_CIM_FIM BIT(3) /* End of Flush Interrupt Mask Bit */
+#define AT_XDMAC_CIM_RBEIM BIT(4) /* Read Bus Error Interrupt Mask Bit */
+#define AT_XDMAC_CIM_WBEIM BIT(5) /* Write Bus Error Interrupt Mask Bit */
+#define AT_XDMAC_CIM_ROIM BIT(6) /* Request Overflow Interrupt Mask Bit */
+#define AT_XDMAC_CIS 0x0C /* Channel Interrupt Status Register */
+#define AT_XDMAC_CIS_BIS BIT(0) /* End of Block Interrupt Status Bit */
+#define AT_XDMAC_CIS_LIS BIT(1) /* End of Linked List Interrupt Status Bit */
+#define AT_XDMAC_CIS_DIS BIT(2) /* End of Disable Interrupt Status Bit */
+#define AT_XDMAC_CIS_FIS BIT(3) /* End of Flush Interrupt Status Bit */
+#define AT_XDMAC_CIS_RBEIS BIT(4) /* Read Bus Error Interrupt Status Bit */
+#define AT_XDMAC_CIS_WBEIS BIT(5) /* Write Bus Error Interrupt Status Bit */
+#define AT_XDMAC_CIS_ROIS BIT(6) /* Request Overflow Interrupt Status Bit */
+#define AT_XDMAC_CSA 0x10 /* Channel Source Address Register */
+#define AT_XDMAC_CDA 0x14 /* Channel Destination Address Register */
+#define AT_XDMAC_CNDA 0x18 /* Channel Next Descriptor Address Register */
+#define AT_XDMAC_CNDA_NDAIF(i) ((i) & 0x1) /* Channel x Next Descriptor Interface */
+#define AT_XDMAC_CNDA_NDA(i) ((i) & 0xfffffffc) /* Channel x Next Descriptor Address */
+#define AT_XDMAC_CNDC 0x1C /* Channel Next Descriptor Control Register */
+#define AT_XDMAC_CNDC_NDE (0x1 << 0) /* Channel x Next Descriptor Enable */
+#define AT_XDMAC_CNDC_NDSUP (0x1 << 1) /* Channel x Next Descriptor Source Update */
+#define AT_XDMAC_CNDC_NDDUP (0x1 << 2) /* Channel x Next Descriptor Destination Update */
+#define AT_XDMAC_CNDC_NDVIEW_MASK GENMASK(28, 27)
+#define AT_XDMAC_CNDC_NDVIEW_NDV0 (0x0 << 3) /* Channel x Next Descriptor View 0 */
+#define AT_XDMAC_CNDC_NDVIEW_NDV1 (0x1 << 3) /* Channel x Next Descriptor View 1 */
+#define AT_XDMAC_CNDC_NDVIEW_NDV2 (0x2 << 3) /* Channel x Next Descriptor View 2 */
+#define AT_XDMAC_CNDC_NDVIEW_NDV3 (0x3 << 3) /* Channel x Next Descriptor View 3 */
+#define AT_XDMAC_CUBC 0x20 /* Channel Microblock Control Register */
+#define AT_XDMAC_CBC 0x24 /* Channel Block Control Register */
+#define AT_XDMAC_CC 0x28 /* Channel Configuration Register */
+#define AT_XDMAC_CC_TYPE (0x1 << 0) /* Channel Transfer Type */
+#define AT_XDMAC_CC_TYPE_MEM_TRAN (0x0 << 0) /* Memory to Memory Transfer */
+#define AT_XDMAC_CC_TYPE_PER_TRAN (0x1 << 0) /* Peripheral to Memory or Memory to Peripheral Transfer */
+#define AT_XDMAC_CC_MBSIZE_MASK (0x3 << 1)
+#define AT_XDMAC_CC_MBSIZE_SINGLE (0x0 << 1)
+#define AT_XDMAC_CC_MBSIZE_FOUR (0x1 << 1)
+#define AT_XDMAC_CC_MBSIZE_EIGHT (0x2 << 1)
+#define AT_XDMAC_CC_MBSIZE_SIXTEEN (0x3 << 1)
+#define AT_XDMAC_CC_DSYNC (0x1 << 4) /* Channel Synchronization */
+#define AT_XDMAC_CC_DSYNC_PER2MEM (0x0 << 4)
+#define AT_XDMAC_CC_DSYNC_MEM2PER (0x1 << 4)
+#define AT_XDMAC_CC_PROT (0x1 << 5) /* Channel Protection */
+#define AT_XDMAC_CC_PROT_SEC (0x0 << 5)
+#define AT_XDMAC_CC_PROT_UNSEC (0x1 << 5)
+#define AT_XDMAC_CC_SWREQ (0x1 << 6) /* Channel Software Request Trigger */
+#define AT_XDMAC_CC_SWREQ_HWR_CONNECTED (0x0 << 6)
+#define AT_XDMAC_CC_SWREQ_SWR_CONNECTED (0x1 << 6)
+#define AT_XDMAC_CC_MEMSET (0x1 << 7) /* Channel Fill Block of memory */
+#define AT_XDMAC_CC_MEMSET_NORMAL_MODE (0x0 << 7)
+#define AT_XDMAC_CC_MEMSET_HW_MODE (0x1 << 7)
+#define AT_XDMAC_CC_CSIZE(i) ((0x7 & (i)) << 8) /* Channel Chunk Size */
+#define AT_XDMAC_CC_DWIDTH_OFFSET 11
+#define AT_XDMAC_CC_DWIDTH_MASK (0x3 << AT_XDMAC_CC_DWIDTH_OFFSET)
+#define AT_XDMAC_CC_DWIDTH(i) ((0x3 & (i)) << AT_XDMAC_CC_DWIDTH_OFFSET) /* Channel Data Width */
+#define AT_XDMAC_CC_DWIDTH_BYTE 0x0
+#define AT_XDMAC_CC_DWIDTH_HALFWORD 0x1
+#define AT_XDMAC_CC_DWIDTH_WORD 0x2
+#define AT_XDMAC_CC_DWIDTH_DWORD 0x3
+#define AT_XDMAC_CC_SIF(i) ((0x1 & (i)) << 13) /* Channel Source Interface Identifier */
+#define AT_XDMAC_CC_DIF(i) ((0x1 & (i)) << 14) /* Channel Destination Interface Identifier */
+#define AT_XDMAC_CC_SAM_MASK (0x3 << 16) /* Channel Source Addressing Mode */
+#define AT_XDMAC_CC_SAM_FIXED_AM (0x0 << 16)
+#define AT_XDMAC_CC_SAM_INCREMENTED_AM (0x1 << 16)
+#define AT_XDMAC_CC_SAM_UBS_AM (0x2 << 16)
+#define AT_XDMAC_CC_SAM_UBS_DS_AM (0x3 << 16)
+#define AT_XDMAC_CC_DAM_MASK (0x3 << 18) /* Channel Source Addressing Mode */
+#define AT_XDMAC_CC_DAM_FIXED_AM (0x0 << 18)
+#define AT_XDMAC_CC_DAM_INCREMENTED_AM (0x1 << 18)
+#define AT_XDMAC_CC_DAM_UBS_AM (0x2 << 18)
+#define AT_XDMAC_CC_DAM_UBS_DS_AM (0x3 << 18)
+#define AT_XDMAC_CC_INITD (0x1 << 21) /* Channel Initialization Terminated (read only) */
+#define AT_XDMAC_CC_INITD_TERMINATED (0x0 << 21)
+#define AT_XDMAC_CC_INITD_IN_PROGRESS (0x1 << 21)
+#define AT_XDMAC_CC_RDIP (0x1 << 22) /* Read in Progress (read only) */
+#define AT_XDMAC_CC_RDIP_DONE (0x0 << 22)
+#define AT_XDMAC_CC_RDIP_IN_PROGRESS (0x1 << 22)
+#define AT_XDMAC_CC_WRIP (0x1 << 23) /* Write in Progress (read only) */
+#define AT_XDMAC_CC_WRIP_DONE (0x0 << 23)
+#define AT_XDMAC_CC_WRIP_IN_PROGRESS (0x1 << 23)
+#define AT_XDMAC_CC_PERID(i) ((0x7f & (i)) << 24) /* Channel Peripheral Identifier */
+#define AT_XDMAC_CDS_MSP 0x2C /* Channel Data Stride Memory Set Pattern */
+#define AT_XDMAC_CSUS 0x30 /* Channel Source Microblock Stride */
+#define AT_XDMAC_CDUS 0x34 /* Channel Destination Microblock Stride */
+
+#define AT_XDMAC_CHAN_REG_BASE 0x50 /* Channel registers base address */
+
+/* Microblock control members */
+#define AT_XDMAC_MBR_UBC_UBLEN_MAX 0xFFFFFFUL /* Maximum Microblock Length */
+#define AT_XDMAC_MBR_UBC_NDE (0x1 << 24) /* Next Descriptor Enable */
+#define AT_XDMAC_MBR_UBC_NSEN (0x1 << 25) /* Next Descriptor Source Update */
+#define AT_XDMAC_MBR_UBC_NDEN (0x1 << 26) /* Next Descriptor Destination Update */
+#define AT_XDMAC_MBR_UBC_NDV0 (0x0 << 27) /* Next Descriptor View 0 */
+#define AT_XDMAC_MBR_UBC_NDV1 (0x1 << 27) /* Next Descriptor View 1 */
+#define AT_XDMAC_MBR_UBC_NDV2 (0x2 << 27) /* Next Descriptor View 2 */
+#define AT_XDMAC_MBR_UBC_NDV3 (0x3 << 27) /* Next Descriptor View 3 */
+
+#define AT_XDMAC_MAX_CHAN 0x20
+#define AT_XDMAC_MAX_CSIZE 16 /* 16 data */
+#define AT_XDMAC_MAX_DWIDTH 8 /* 64 bits */
+#define AT_XDMAC_RESIDUE_MAX_RETRIES 5
+
+#define AT_XDMAC_DMA_BUSWIDTHS\
+ (BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) |\
+ BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |\
+ BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |\
+ BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |\
+ BIT(DMA_SLAVE_BUSWIDTH_8_BYTES))
+
+enum atc_status {
+ AT_XDMAC_CHAN_IS_CYCLIC = 0,
+ AT_XDMAC_CHAN_IS_PAUSED,
+};
+
+/* ----- Channels ----- */
+struct at_xdmac_chan {
+ struct dma_chan chan;
+ void __iomem *ch_regs;
+ u32 mask; /* Channel Mask */
+ u32 cfg; /* Channel Configuration Register */
+ u8 perid; /* Peripheral ID */
+ u8 perif; /* Peripheral Interface */
+ u8 memif; /* Memory Interface */
+ u32 save_cc;
+ u32 save_cim;
+ u32 save_cnda;
+ u32 save_cndc;
+ u32 irq_status;
+ unsigned long status;
+ struct tasklet_struct tasklet;
+ struct dma_slave_config sconfig;
+
+ spinlock_t lock;
+
+ struct list_head xfers_list;
+ struct list_head free_descs_list;
+};
+
+
+/* ----- Controller ----- */
+struct at_xdmac {
+ struct dma_device dma;
+ void __iomem *regs;
+ int irq;
+ struct clk *clk;
+ u32 save_gim;
+ u32 save_gs;
+ struct dma_pool *at_xdmac_desc_pool;
+ struct at_xdmac_chan chan[];
+};
+
+
+/* ----- Descriptors ----- */
+
+/* Linked List Descriptor */
+struct at_xdmac_lld {
+ u32 mbr_nda; /* Next Descriptor Member */
+ u32 mbr_ubc; /* Microblock Control Member */
+ u32 mbr_sa; /* Source Address Member */
+ u32 mbr_da; /* Destination Address Member */
+ u32 mbr_cfg; /* Configuration Register */
+ u32 mbr_bc; /* Block Control Register */
+ u32 mbr_ds; /* Data Stride Register */
+ u32 mbr_sus; /* Source Microblock Stride Register */
+ u32 mbr_dus; /* Destination Microblock Stride Register */
+};
+
+/* 64-bit alignment needed to update CNDA and CUBC registers in an atomic way. */
+struct at_xdmac_desc {
+ struct at_xdmac_lld lld;
+ enum dma_transfer_direction direction;
+ struct dma_async_tx_descriptor tx_dma_desc;
+ struct list_head desc_node;
+ /* Following members are only used by the first descriptor */
+ bool active_xfer;
+ unsigned int xfer_size;
+ struct list_head descs_list;
+ struct list_head xfer_node;
+} __aligned(sizeof(u64));
+
+static inline void __iomem *at_xdmac_chan_reg_base(struct at_xdmac *atxdmac, unsigned int chan_nb)
+{
+ return atxdmac->regs + (AT_XDMAC_CHAN_REG_BASE + chan_nb * 0x40);
+}
+
+#define at_xdmac_read(atxdmac, reg) readl_relaxed((atxdmac)->regs + (reg))
+#define at_xdmac_write(atxdmac, reg, value) \
+ writel_relaxed((value), (atxdmac)->regs + (reg))
+
+#define at_xdmac_chan_read(atchan, reg) readl_relaxed((atchan)->ch_regs + (reg))
+#define at_xdmac_chan_write(atchan, reg, value) writel_relaxed((value), (atchan)->ch_regs + (reg))
+
+static inline struct at_xdmac_chan *to_at_xdmac_chan(struct dma_chan *dchan)
+{
+ return container_of(dchan, struct at_xdmac_chan, chan);
+}
+
+static struct device *chan2dev(struct dma_chan *chan)
+{
+ return &chan->dev->device;
+}
+
+static inline struct at_xdmac *to_at_xdmac(struct dma_device *ddev)
+{
+ return container_of(ddev, struct at_xdmac, dma);
+}
+
+static inline struct at_xdmac_desc *txd_to_at_desc(struct dma_async_tx_descriptor *txd)
+{
+ return container_of(txd, struct at_xdmac_desc, tx_dma_desc);
+}
+
+static inline int at_xdmac_chan_is_cyclic(struct at_xdmac_chan *atchan)
+{
+ return test_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status);
+}
+
+static inline int at_xdmac_chan_is_paused(struct at_xdmac_chan *atchan)
+{
+ return test_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
+}
+
+static inline int at_xdmac_csize(u32 maxburst)
+{
+ int csize;
+
+ csize = ffs(maxburst) - 1;
+ if (csize > 4)
+ csize = -EINVAL;
+
+ return csize;
+};
+
+static inline bool at_xdmac_chan_is_peripheral_xfer(u32 cfg)
+{
+ return cfg & AT_XDMAC_CC_TYPE_PER_TRAN;
+}
+
+static inline u8 at_xdmac_get_dwidth(u32 cfg)
+{
+ return (cfg & AT_XDMAC_CC_DWIDTH_MASK) >> AT_XDMAC_CC_DWIDTH_OFFSET;
+};
+
+static unsigned int init_nr_desc_per_channel = 64;
+module_param(init_nr_desc_per_channel, uint, 0644);
+MODULE_PARM_DESC(init_nr_desc_per_channel,
+ "initial descriptors per channel (default: 64)");
+
+
+static bool at_xdmac_chan_is_enabled(struct at_xdmac_chan *atchan)
+{
+ return at_xdmac_chan_read(atchan, AT_XDMAC_GS) & atchan->mask;
+}
+
+static void at_xdmac_off(struct at_xdmac *atxdmac)
+{
+ at_xdmac_write(atxdmac, AT_XDMAC_GD, -1L);
+
+ /* Wait that all chans are disabled. */
+ while (at_xdmac_read(atxdmac, AT_XDMAC_GS))
+ cpu_relax();
+
+ at_xdmac_write(atxdmac, AT_XDMAC_GID, -1L);
+}
+
+/* Call with lock hold. */
+static void at_xdmac_start_xfer(struct at_xdmac_chan *atchan,
+ struct at_xdmac_desc *first)
+{
+ struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
+ u32 reg;
+
+ dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, first);
+
+ /* Set transfer as active to not try to start it again. */
+ first->active_xfer = true;
+
+ /* Tell xdmac where to get the first descriptor. */
+ reg = AT_XDMAC_CNDA_NDA(first->tx_dma_desc.phys)
+ | AT_XDMAC_CNDA_NDAIF(atchan->memif);
+ at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, reg);
+
+ /*
+ * When doing non cyclic transfer we need to use the next
+ * descriptor view 2 since some fields of the configuration register
+ * depend on transfer size and src/dest addresses.
+ */
+ if (at_xdmac_chan_is_cyclic(atchan))
+ reg = AT_XDMAC_CNDC_NDVIEW_NDV1;
+ else if ((first->lld.mbr_ubc &
+ AT_XDMAC_CNDC_NDVIEW_MASK) == AT_XDMAC_MBR_UBC_NDV3)
+ reg = AT_XDMAC_CNDC_NDVIEW_NDV3;
+ else
+ reg = AT_XDMAC_CNDC_NDVIEW_NDV2;
+ /*
+ * Even if the register will be updated from the configuration in the
+ * descriptor when using view 2 or higher, the PROT bit won't be set
+ * properly. This bit can be modified only by using the channel
+ * configuration register.
+ */
+ at_xdmac_chan_write(atchan, AT_XDMAC_CC, first->lld.mbr_cfg);
+
+ reg |= AT_XDMAC_CNDC_NDDUP
+ | AT_XDMAC_CNDC_NDSUP
+ | AT_XDMAC_CNDC_NDE;
+ at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, reg);
+
+ dev_vdbg(chan2dev(&atchan->chan),
+ "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
+ __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
+
+ at_xdmac_chan_write(atchan, AT_XDMAC_CID, 0xffffffff);
+ reg = AT_XDMAC_CIE_RBEIE | AT_XDMAC_CIE_WBEIE;
+ /*
+ * Request Overflow Error is only for peripheral synchronized transfers
+ */
+ if (at_xdmac_chan_is_peripheral_xfer(first->lld.mbr_cfg))
+ reg |= AT_XDMAC_CIE_ROIE;
+
+ /*
+ * There is no end of list when doing cyclic dma, we need to get
+ * an interrupt after each periods.
+ */
+ if (at_xdmac_chan_is_cyclic(atchan))
+ at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
+ reg | AT_XDMAC_CIE_BIE);
+ else
+ at_xdmac_chan_write(atchan, AT_XDMAC_CIE,
+ reg | AT_XDMAC_CIE_LIE);
+ at_xdmac_write(atxdmac, AT_XDMAC_GIE, atchan->mask);
+ dev_vdbg(chan2dev(&atchan->chan),
+ "%s: enable channel (0x%08x)\n", __func__, atchan->mask);
+ wmb();
+ at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
+
+ dev_vdbg(chan2dev(&atchan->chan),
+ "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
+ __func__, at_xdmac_chan_read(atchan, AT_XDMAC_CC),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
+
+}
+
+static dma_cookie_t at_xdmac_tx_submit(struct dma_async_tx_descriptor *tx)
+{
+ struct at_xdmac_desc *desc = txd_to_at_desc(tx);
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(tx->chan);
+ dma_cookie_t cookie;
+ unsigned long irqflags;
+
+ spin_lock_irqsave(&atchan->lock, irqflags);
+ cookie = dma_cookie_assign(tx);
+
+ list_add_tail(&desc->xfer_node, &atchan->xfers_list);
+ spin_unlock_irqrestore(&atchan->lock, irqflags);
+
+ dev_vdbg(chan2dev(tx->chan), "%s: atchan 0x%p, add desc 0x%p to xfers_list\n",
+ __func__, atchan, desc);
+
+ return cookie;
+}
+
+static struct at_xdmac_desc *at_xdmac_alloc_desc(struct dma_chan *chan,
+ gfp_t gfp_flags)
+{
+ struct at_xdmac_desc *desc;
+ struct at_xdmac *atxdmac = to_at_xdmac(chan->device);
+ dma_addr_t phys;
+
+ desc = dma_pool_zalloc(atxdmac->at_xdmac_desc_pool, gfp_flags, &phys);
+ if (desc) {
+ INIT_LIST_HEAD(&desc->descs_list);
+ dma_async_tx_descriptor_init(&desc->tx_dma_desc, chan);
+ desc->tx_dma_desc.tx_submit = at_xdmac_tx_submit;
+ desc->tx_dma_desc.phys = phys;
+ }
+
+ return desc;
+}
+
+static void at_xdmac_init_used_desc(struct at_xdmac_desc *desc)
+{
+ memset(&desc->lld, 0, sizeof(desc->lld));
+ INIT_LIST_HEAD(&desc->descs_list);
+ desc->direction = DMA_TRANS_NONE;
+ desc->xfer_size = 0;
+ desc->active_xfer = false;
+}
+
+/* Call must be protected by lock. */
+static struct at_xdmac_desc *at_xdmac_get_desc(struct at_xdmac_chan *atchan)
+{
+ struct at_xdmac_desc *desc;
+
+ if (list_empty(&atchan->free_descs_list)) {
+ desc = at_xdmac_alloc_desc(&atchan->chan, GFP_NOWAIT);
+ } else {
+ desc = list_first_entry(&atchan->free_descs_list,
+ struct at_xdmac_desc, desc_node);
+ list_del(&desc->desc_node);
+ at_xdmac_init_used_desc(desc);
+ }
+
+ return desc;
+}
+
+static void at_xdmac_queue_desc(struct dma_chan *chan,
+ struct at_xdmac_desc *prev,
+ struct at_xdmac_desc *desc)
+{
+ if (!prev || !desc)
+ return;
+
+ prev->lld.mbr_nda = desc->tx_dma_desc.phys;
+ prev->lld.mbr_ubc |= AT_XDMAC_MBR_UBC_NDE;
+
+ dev_dbg(chan2dev(chan), "%s: chain lld: prev=0x%p, mbr_nda=%pad\n",
+ __func__, prev, &prev->lld.mbr_nda);
+}
+
+static inline void at_xdmac_increment_block_count(struct dma_chan *chan,
+ struct at_xdmac_desc *desc)
+{
+ if (!desc)
+ return;
+
+ desc->lld.mbr_bc++;
+
+ dev_dbg(chan2dev(chan),
+ "%s: incrementing the block count of the desc 0x%p\n",
+ __func__, desc);
+}
+
+static struct dma_chan *at_xdmac_xlate(struct of_phandle_args *dma_spec,
+ struct of_dma *of_dma)
+{
+ struct at_xdmac *atxdmac = of_dma->of_dma_data;
+ struct at_xdmac_chan *atchan;
+ struct dma_chan *chan;
+ struct device *dev = atxdmac->dma.dev;
+
+ if (dma_spec->args_count != 1) {
+ dev_err(dev, "dma phandler args: bad number of args\n");
+ return NULL;
+ }
+
+ chan = dma_get_any_slave_channel(&atxdmac->dma);
+ if (!chan) {
+ dev_err(dev, "can't get a dma channel\n");
+ return NULL;
+ }
+
+ atchan = to_at_xdmac_chan(chan);
+ atchan->memif = AT91_XDMAC_DT_GET_MEM_IF(dma_spec->args[0]);
+ atchan->perif = AT91_XDMAC_DT_GET_PER_IF(dma_spec->args[0]);
+ atchan->perid = AT91_XDMAC_DT_GET_PERID(dma_spec->args[0]);
+ dev_dbg(dev, "chan dt cfg: memif=%u perif=%u perid=%u\n",
+ atchan->memif, atchan->perif, atchan->perid);
+
+ return chan;
+}
+
+static int at_xdmac_compute_chan_conf(struct dma_chan *chan,
+ enum dma_transfer_direction direction)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ int csize, dwidth;
+
+ if (direction == DMA_DEV_TO_MEM) {
+ atchan->cfg =
+ AT91_XDMAC_DT_PERID(atchan->perid)
+ | AT_XDMAC_CC_DAM_INCREMENTED_AM
+ | AT_XDMAC_CC_SAM_FIXED_AM
+ | AT_XDMAC_CC_DIF(atchan->memif)
+ | AT_XDMAC_CC_SIF(atchan->perif)
+ | AT_XDMAC_CC_SWREQ_HWR_CONNECTED
+ | AT_XDMAC_CC_DSYNC_PER2MEM
+ | AT_XDMAC_CC_MBSIZE_SIXTEEN
+ | AT_XDMAC_CC_TYPE_PER_TRAN;
+ csize = ffs(atchan->sconfig.src_maxburst) - 1;
+ if (csize < 0) {
+ dev_err(chan2dev(chan), "invalid src maxburst value\n");
+ return -EINVAL;
+ }
+ atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
+ dwidth = ffs(atchan->sconfig.src_addr_width) - 1;
+ if (dwidth < 0) {
+ dev_err(chan2dev(chan), "invalid src addr width value\n");
+ return -EINVAL;
+ }
+ atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
+ } else if (direction == DMA_MEM_TO_DEV) {
+ atchan->cfg =
+ AT91_XDMAC_DT_PERID(atchan->perid)
+ | AT_XDMAC_CC_DAM_FIXED_AM
+ | AT_XDMAC_CC_SAM_INCREMENTED_AM
+ | AT_XDMAC_CC_DIF(atchan->perif)
+ | AT_XDMAC_CC_SIF(atchan->memif)
+ | AT_XDMAC_CC_SWREQ_HWR_CONNECTED
+ | AT_XDMAC_CC_DSYNC_MEM2PER
+ | AT_XDMAC_CC_MBSIZE_SIXTEEN
+ | AT_XDMAC_CC_TYPE_PER_TRAN;
+ csize = ffs(atchan->sconfig.dst_maxburst) - 1;
+ if (csize < 0) {
+ dev_err(chan2dev(chan), "invalid src maxburst value\n");
+ return -EINVAL;
+ }
+ atchan->cfg |= AT_XDMAC_CC_CSIZE(csize);
+ dwidth = ffs(atchan->sconfig.dst_addr_width) - 1;
+ if (dwidth < 0) {
+ dev_err(chan2dev(chan), "invalid dst addr width value\n");
+ return -EINVAL;
+ }
+ atchan->cfg |= AT_XDMAC_CC_DWIDTH(dwidth);
+ }
+
+ dev_dbg(chan2dev(chan), "%s: cfg=0x%08x\n", __func__, atchan->cfg);
+
+ return 0;
+}
+
+/*
+ * Only check that maxburst and addr width values are supported by the
+ * the controller but not that the configuration is good to perform the
+ * transfer since we don't know the direction at this stage.
+ */
+static int at_xdmac_check_slave_config(struct dma_slave_config *sconfig)
+{
+ if ((sconfig->src_maxburst > AT_XDMAC_MAX_CSIZE)
+ || (sconfig->dst_maxburst > AT_XDMAC_MAX_CSIZE))
+ return -EINVAL;
+
+ if ((sconfig->src_addr_width > AT_XDMAC_MAX_DWIDTH)
+ || (sconfig->dst_addr_width > AT_XDMAC_MAX_DWIDTH))
+ return -EINVAL;
+
+ return 0;
+}
+
+static int at_xdmac_set_slave_config(struct dma_chan *chan,
+ struct dma_slave_config *sconfig)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+
+ if (at_xdmac_check_slave_config(sconfig)) {
+ dev_err(chan2dev(chan), "invalid slave configuration\n");
+ return -EINVAL;
+ }
+
+ memcpy(&atchan->sconfig, sconfig, sizeof(atchan->sconfig));
+
+ return 0;
+}
+
+static struct dma_async_tx_descriptor *
+at_xdmac_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 at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ struct at_xdmac_desc *first = NULL, *prev = NULL;
+ struct scatterlist *sg;
+ int i;
+ unsigned int xfer_size = 0;
+ unsigned long irqflags;
+ struct dma_async_tx_descriptor *ret = NULL;
+
+ if (!sgl)
+ return NULL;
+
+ if (!is_slave_direction(direction)) {
+ dev_err(chan2dev(chan), "invalid DMA direction\n");
+ return NULL;
+ }
+
+ dev_dbg(chan2dev(chan), "%s: sg_len=%d, dir=%s, flags=0x%lx\n",
+ __func__, sg_len,
+ direction == DMA_MEM_TO_DEV ? "to device" : "from device",
+ flags);
+
+ /* Protect dma_sconfig field that can be modified by set_slave_conf. */
+ spin_lock_irqsave(&atchan->lock, irqflags);
+
+ if (at_xdmac_compute_chan_conf(chan, direction))
+ goto spin_unlock;
+
+ /* Prepare descriptors. */
+ for_each_sg(sgl, sg, sg_len, i) {
+ struct at_xdmac_desc *desc = NULL;
+ u32 len, mem, dwidth, fixed_dwidth;
+
+ len = sg_dma_len(sg);
+ mem = sg_dma_address(sg);
+ if (unlikely(!len)) {
+ dev_err(chan2dev(chan), "sg data length is zero\n");
+ goto spin_unlock;
+ }
+ dev_dbg(chan2dev(chan), "%s: * sg%d len=%u, mem=0x%08x\n",
+ __func__, i, len, mem);
+
+ desc = at_xdmac_get_desc(atchan);
+ if (!desc) {
+ dev_err(chan2dev(chan), "can't get descriptor\n");
+ if (first)
+ list_splice_tail_init(&first->descs_list,
+ &atchan->free_descs_list);
+ goto spin_unlock;
+ }
+
+ /* Linked list descriptor setup. */
+ if (direction == DMA_DEV_TO_MEM) {
+ desc->lld.mbr_sa = atchan->sconfig.src_addr;
+ desc->lld.mbr_da = mem;
+ } else {
+ desc->lld.mbr_sa = mem;
+ desc->lld.mbr_da = atchan->sconfig.dst_addr;
+ }
+ dwidth = at_xdmac_get_dwidth(atchan->cfg);
+ fixed_dwidth = IS_ALIGNED(len, 1 << dwidth)
+ ? dwidth
+ : AT_XDMAC_CC_DWIDTH_BYTE;
+ desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2 /* next descriptor view */
+ | AT_XDMAC_MBR_UBC_NDEN /* next descriptor dst parameter update */
+ | AT_XDMAC_MBR_UBC_NSEN /* next descriptor src parameter update */
+ | (len >> fixed_dwidth); /* microblock length */
+ desc->lld.mbr_cfg = (atchan->cfg & ~AT_XDMAC_CC_DWIDTH_MASK) |
+ AT_XDMAC_CC_DWIDTH(fixed_dwidth);
+ dev_dbg(chan2dev(chan),
+ "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
+ __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
+
+ /* Chain lld. */
+ if (prev)
+ at_xdmac_queue_desc(chan, prev, desc);
+
+ prev = desc;
+ if (!first)
+ first = desc;
+
+ dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
+ __func__, desc, first);
+ list_add_tail(&desc->desc_node, &first->descs_list);
+ xfer_size += len;
+ }
+
+
+ first->tx_dma_desc.flags = flags;
+ first->xfer_size = xfer_size;
+ first->direction = direction;
+ ret = &first->tx_dma_desc;
+
+spin_unlock:
+ spin_unlock_irqrestore(&atchan->lock, irqflags);
+ return ret;
+}
+
+static struct dma_async_tx_descriptor *
+at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr,
+ size_t buf_len, size_t period_len,
+ enum dma_transfer_direction direction,
+ unsigned long flags)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ struct at_xdmac_desc *first = NULL, *prev = NULL;
+ unsigned int periods = buf_len / period_len;
+ int i;
+ unsigned long irqflags;
+
+ dev_dbg(chan2dev(chan), "%s: buf_addr=%pad, buf_len=%zd, period_len=%zd, dir=%s, flags=0x%lx\n",
+ __func__, &buf_addr, buf_len, period_len,
+ direction == DMA_MEM_TO_DEV ? "mem2per" : "per2mem", flags);
+
+ if (!is_slave_direction(direction)) {
+ dev_err(chan2dev(chan), "invalid DMA direction\n");
+ return NULL;
+ }
+
+ if (test_and_set_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status)) {
+ dev_err(chan2dev(chan), "channel currently used\n");
+ return NULL;
+ }
+
+ if (at_xdmac_compute_chan_conf(chan, direction))
+ return NULL;
+
+ for (i = 0; i < periods; i++) {
+ struct at_xdmac_desc *desc = NULL;
+
+ spin_lock_irqsave(&atchan->lock, irqflags);
+ desc = at_xdmac_get_desc(atchan);
+ if (!desc) {
+ dev_err(chan2dev(chan), "can't get descriptor\n");
+ if (first)
+ list_splice_tail_init(&first->descs_list,
+ &atchan->free_descs_list);
+ spin_unlock_irqrestore(&atchan->lock, irqflags);
+ return NULL;
+ }
+ spin_unlock_irqrestore(&atchan->lock, irqflags);
+ dev_dbg(chan2dev(chan),
+ "%s: desc=0x%p, tx_dma_desc.phys=%pad\n",
+ __func__, desc, &desc->tx_dma_desc.phys);
+
+ if (direction == DMA_DEV_TO_MEM) {
+ desc->lld.mbr_sa = atchan->sconfig.src_addr;
+ desc->lld.mbr_da = buf_addr + i * period_len;
+ } else {
+ desc->lld.mbr_sa = buf_addr + i * period_len;
+ desc->lld.mbr_da = atchan->sconfig.dst_addr;
+ }
+ desc->lld.mbr_cfg = atchan->cfg;
+ desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV1
+ | AT_XDMAC_MBR_UBC_NDEN
+ | AT_XDMAC_MBR_UBC_NSEN
+ | period_len >> at_xdmac_get_dwidth(desc->lld.mbr_cfg);
+
+ dev_dbg(chan2dev(chan),
+ "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
+ __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
+
+ /* Chain lld. */
+ if (prev)
+ at_xdmac_queue_desc(chan, prev, desc);
+
+ prev = desc;
+ if (!first)
+ first = desc;
+
+ dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
+ __func__, desc, first);
+ list_add_tail(&desc->desc_node, &first->descs_list);
+ }
+
+ at_xdmac_queue_desc(chan, prev, first);
+ first->tx_dma_desc.flags = flags;
+ first->xfer_size = buf_len;
+ first->direction = direction;
+
+ return &first->tx_dma_desc;
+}
+
+static inline u32 at_xdmac_align_width(struct dma_chan *chan, dma_addr_t addr)
+{
+ u32 width;
+
+ /*
+ * Check address alignment to select the greater data width we
+ * can use.
+ *
+ * Some XDMAC implementations don't provide dword transfer, in
+ * this case selecting dword has the same behavior as
+ * selecting word transfers.
+ */
+ if (!(addr & 7)) {
+ width = AT_XDMAC_CC_DWIDTH_DWORD;
+ dev_dbg(chan2dev(chan), "%s: dwidth: double word\n", __func__);
+ } else if (!(addr & 3)) {
+ width = AT_XDMAC_CC_DWIDTH_WORD;
+ dev_dbg(chan2dev(chan), "%s: dwidth: word\n", __func__);
+ } else if (!(addr & 1)) {
+ width = AT_XDMAC_CC_DWIDTH_HALFWORD;
+ dev_dbg(chan2dev(chan), "%s: dwidth: half word\n", __func__);
+ } else {
+ width = AT_XDMAC_CC_DWIDTH_BYTE;
+ dev_dbg(chan2dev(chan), "%s: dwidth: byte\n", __func__);
+ }
+
+ return width;
+}
+
+static struct at_xdmac_desc *
+at_xdmac_interleaved_queue_desc(struct dma_chan *chan,
+ struct at_xdmac_chan *atchan,
+ struct at_xdmac_desc *prev,
+ dma_addr_t src, dma_addr_t dst,
+ struct dma_interleaved_template *xt,
+ struct data_chunk *chunk)
+{
+ struct at_xdmac_desc *desc;
+ u32 dwidth;
+ unsigned long flags;
+ size_t ublen;
+ /*
+ * WARNING: The channel configuration is set here since there is no
+ * dmaengine_slave_config call in this case. Moreover we don't know the
+ * direction, it involves we can't dynamically set the source and dest
+ * interface so we have to use the same one. Only interface 0 allows EBI
+ * access. Hopefully we can access DDR through both ports (at least on
+ * SAMA5D4x), so we can use the same interface for source and dest,
+ * that solves the fact we don't know the direction.
+ * ERRATA: Even if useless for memory transfers, the PERID has to not
+ * match the one of another channel. If not, it could lead to spurious
+ * flag status.
+ */
+ u32 chan_cc = AT_XDMAC_CC_PERID(0x3f)
+ | AT_XDMAC_CC_DIF(0)
+ | AT_XDMAC_CC_SIF(0)
+ | AT_XDMAC_CC_MBSIZE_SIXTEEN
+ | AT_XDMAC_CC_TYPE_MEM_TRAN;
+
+ dwidth = at_xdmac_align_width(chan, src | dst | chunk->size);
+ if (chunk->size >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
+ dev_dbg(chan2dev(chan),
+ "%s: chunk too big (%zu, max size %lu)...\n",
+ __func__, chunk->size,
+ AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth);
+ return NULL;
+ }
+
+ if (prev)
+ dev_dbg(chan2dev(chan),
+ "Adding items at the end of desc 0x%p\n", prev);
+
+ if (xt->src_inc) {
+ if (xt->src_sgl)
+ chan_cc |= AT_XDMAC_CC_SAM_UBS_AM;
+ else
+ chan_cc |= AT_XDMAC_CC_SAM_INCREMENTED_AM;
+ }
+
+ if (xt->dst_inc) {
+ if (xt->dst_sgl)
+ chan_cc |= AT_XDMAC_CC_DAM_UBS_AM;
+ else
+ chan_cc |= AT_XDMAC_CC_DAM_INCREMENTED_AM;
+ }
+
+ spin_lock_irqsave(&atchan->lock, flags);
+ desc = at_xdmac_get_desc(atchan);
+ spin_unlock_irqrestore(&atchan->lock, flags);
+ if (!desc) {
+ dev_err(chan2dev(chan), "can't get descriptor\n");
+ return NULL;
+ }
+
+ chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
+
+ ublen = chunk->size >> dwidth;
+
+ desc->lld.mbr_sa = src;
+ desc->lld.mbr_da = dst;
+ desc->lld.mbr_sus = dmaengine_get_src_icg(xt, chunk);
+ desc->lld.mbr_dus = dmaengine_get_dst_icg(xt, chunk);
+
+ desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
+ | AT_XDMAC_MBR_UBC_NDEN
+ | AT_XDMAC_MBR_UBC_NSEN
+ | ublen;
+ desc->lld.mbr_cfg = chan_cc;
+
+ dev_dbg(chan2dev(chan),
+ "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
+ __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da,
+ desc->lld.mbr_ubc, desc->lld.mbr_cfg);
+
+ /* Chain lld. */
+ if (prev)
+ at_xdmac_queue_desc(chan, prev, desc);
+
+ return desc;
+}
+
+static struct dma_async_tx_descriptor *
+at_xdmac_prep_interleaved(struct dma_chan *chan,
+ struct dma_interleaved_template *xt,
+ unsigned long flags)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ struct at_xdmac_desc *prev = NULL, *first = NULL;
+ dma_addr_t dst_addr, src_addr;
+ size_t src_skip = 0, dst_skip = 0, len = 0;
+ struct data_chunk *chunk;
+ int i;
+
+ if (!xt || !xt->numf || (xt->dir != DMA_MEM_TO_MEM))
+ return NULL;
+
+ /*
+ * TODO: Handle the case where we have to repeat a chain of
+ * descriptors...
+ */
+ if ((xt->numf > 1) && (xt->frame_size > 1))
+ return NULL;
+
+ dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, numf=%zu, frame_size=%zu, flags=0x%lx\n",
+ __func__, &xt->src_start, &xt->dst_start, xt->numf,
+ xt->frame_size, flags);
+
+ src_addr = xt->src_start;
+ dst_addr = xt->dst_start;
+
+ if (xt->numf > 1) {
+ first = at_xdmac_interleaved_queue_desc(chan, atchan,
+ NULL,
+ src_addr, dst_addr,
+ xt, xt->sgl);
+ if (!first)
+ return NULL;
+
+ /* Length of the block is (BLEN+1) microblocks. */
+ for (i = 0; i < xt->numf - 1; i++)
+ at_xdmac_increment_block_count(chan, first);
+
+ dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
+ __func__, first, first);
+ list_add_tail(&first->desc_node, &first->descs_list);
+ } else {
+ for (i = 0; i < xt->frame_size; i++) {
+ size_t src_icg = 0, dst_icg = 0;
+ struct at_xdmac_desc *desc;
+
+ chunk = xt->sgl + i;
+
+ dst_icg = dmaengine_get_dst_icg(xt, chunk);
+ src_icg = dmaengine_get_src_icg(xt, chunk);
+
+ src_skip = chunk->size + src_icg;
+ dst_skip = chunk->size + dst_icg;
+
+ dev_dbg(chan2dev(chan),
+ "%s: chunk size=%zu, src icg=%zu, dst icg=%zu\n",
+ __func__, chunk->size, src_icg, dst_icg);
+
+ desc = at_xdmac_interleaved_queue_desc(chan, atchan,
+ prev,
+ src_addr, dst_addr,
+ xt, chunk);
+ if (!desc) {
+ if (first)
+ list_splice_tail_init(&first->descs_list,
+ &atchan->free_descs_list);
+ return NULL;
+ }
+
+ if (!first)
+ first = desc;
+
+ dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
+ __func__, desc, first);
+ list_add_tail(&desc->desc_node, &first->descs_list);
+
+ if (xt->src_sgl)
+ src_addr += src_skip;
+
+ if (xt->dst_sgl)
+ dst_addr += dst_skip;
+
+ len += chunk->size;
+ prev = desc;
+ }
+ }
+
+ first->tx_dma_desc.cookie = -EBUSY;
+ first->tx_dma_desc.flags = flags;
+ first->xfer_size = len;
+
+ return &first->tx_dma_desc;
+}
+
+static struct dma_async_tx_descriptor *
+at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
+ size_t len, unsigned long flags)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ struct at_xdmac_desc *first = NULL, *prev = NULL;
+ size_t remaining_size = len, xfer_size = 0, ublen;
+ dma_addr_t src_addr = src, dst_addr = dest;
+ u32 dwidth;
+ /*
+ * WARNING: We don't know the direction, it involves we can't
+ * dynamically set the source and dest interface so we have to use the
+ * same one. Only interface 0 allows EBI access. Hopefully we can
+ * access DDR through both ports (at least on SAMA5D4x), so we can use
+ * the same interface for source and dest, that solves the fact we
+ * don't know the direction.
+ * ERRATA: Even if useless for memory transfers, the PERID has to not
+ * match the one of another channel. If not, it could lead to spurious
+ * flag status.
+ */
+ u32 chan_cc = AT_XDMAC_CC_PERID(0x3f)
+ | AT_XDMAC_CC_DAM_INCREMENTED_AM
+ | AT_XDMAC_CC_SAM_INCREMENTED_AM
+ | AT_XDMAC_CC_DIF(0)
+ | AT_XDMAC_CC_SIF(0)
+ | AT_XDMAC_CC_MBSIZE_SIXTEEN
+ | AT_XDMAC_CC_TYPE_MEM_TRAN;
+ unsigned long irqflags;
+
+ dev_dbg(chan2dev(chan), "%s: src=%pad, dest=%pad, len=%zd, flags=0x%lx\n",
+ __func__, &src, &dest, len, flags);
+
+ if (unlikely(!len))
+ return NULL;
+
+ dwidth = at_xdmac_align_width(chan, src_addr | dst_addr);
+
+ /* Prepare descriptors. */
+ while (remaining_size) {
+ struct at_xdmac_desc *desc = NULL;
+
+ dev_dbg(chan2dev(chan), "%s: remaining_size=%zu\n", __func__, remaining_size);
+
+ spin_lock_irqsave(&atchan->lock, irqflags);
+ desc = at_xdmac_get_desc(atchan);
+ spin_unlock_irqrestore(&atchan->lock, irqflags);
+ if (!desc) {
+ dev_err(chan2dev(chan), "can't get descriptor\n");
+ if (first)
+ list_splice_tail_init(&first->descs_list,
+ &atchan->free_descs_list);
+ return NULL;
+ }
+
+ /* Update src and dest addresses. */
+ src_addr += xfer_size;
+ dst_addr += xfer_size;
+
+ if (remaining_size >= AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)
+ xfer_size = AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth;
+ else
+ xfer_size = remaining_size;
+
+ dev_dbg(chan2dev(chan), "%s: xfer_size=%zu\n", __func__, xfer_size);
+
+ /* Check remaining length and change data width if needed. */
+ dwidth = at_xdmac_align_width(chan,
+ src_addr | dst_addr | xfer_size);
+ chan_cc &= ~AT_XDMAC_CC_DWIDTH_MASK;
+ chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
+
+ ublen = xfer_size >> dwidth;
+ remaining_size -= xfer_size;
+
+ desc->lld.mbr_sa = src_addr;
+ desc->lld.mbr_da = dst_addr;
+ desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2
+ | AT_XDMAC_MBR_UBC_NDEN
+ | AT_XDMAC_MBR_UBC_NSEN
+ | ublen;
+ desc->lld.mbr_cfg = chan_cc;
+
+ dev_dbg(chan2dev(chan),
+ "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
+ __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc, desc->lld.mbr_cfg);
+
+ /* Chain lld. */
+ if (prev)
+ at_xdmac_queue_desc(chan, prev, desc);
+
+ prev = desc;
+ if (!first)
+ first = desc;
+
+ dev_dbg(chan2dev(chan), "%s: add desc 0x%p to descs_list 0x%p\n",
+ __func__, desc, first);
+ list_add_tail(&desc->desc_node, &first->descs_list);
+ }
+
+ first->tx_dma_desc.flags = flags;
+ first->xfer_size = len;
+
+ return &first->tx_dma_desc;
+}
+
+static struct at_xdmac_desc *at_xdmac_memset_create_desc(struct dma_chan *chan,
+ struct at_xdmac_chan *atchan,
+ dma_addr_t dst_addr,
+ size_t len,
+ int value)
+{
+ struct at_xdmac_desc *desc;
+ unsigned long flags;
+ size_t ublen;
+ u32 dwidth;
+ /*
+ * WARNING: The channel configuration is set here since there is no
+ * dmaengine_slave_config call in this case. Moreover we don't know the
+ * direction, it involves we can't dynamically set the source and dest
+ * interface so we have to use the same one. Only interface 0 allows EBI
+ * access. Hopefully we can access DDR through both ports (at least on
+ * SAMA5D4x), so we can use the same interface for source and dest,
+ * that solves the fact we don't know the direction.
+ * ERRATA: Even if useless for memory transfers, the PERID has to not
+ * match the one of another channel. If not, it could lead to spurious
+ * flag status.
+ */
+ u32 chan_cc = AT_XDMAC_CC_PERID(0x3f)
+ | AT_XDMAC_CC_DAM_UBS_AM
+ | AT_XDMAC_CC_SAM_INCREMENTED_AM
+ | AT_XDMAC_CC_DIF(0)
+ | AT_XDMAC_CC_SIF(0)
+ | AT_XDMAC_CC_MBSIZE_SIXTEEN
+ | AT_XDMAC_CC_MEMSET_HW_MODE
+ | AT_XDMAC_CC_TYPE_MEM_TRAN;
+
+ dwidth = at_xdmac_align_width(chan, dst_addr);
+
+ if (len >= (AT_XDMAC_MBR_UBC_UBLEN_MAX << dwidth)) {
+ dev_err(chan2dev(chan),
+ "%s: Transfer too large, aborting...\n",
+ __func__);
+ return NULL;
+ }
+
+ spin_lock_irqsave(&atchan->lock, flags);
+ desc = at_xdmac_get_desc(atchan);
+ spin_unlock_irqrestore(&atchan->lock, flags);
+ if (!desc) {
+ dev_err(chan2dev(chan), "can't get descriptor\n");
+ return NULL;
+ }
+
+ chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth);
+
+ ublen = len >> dwidth;
+
+ desc->lld.mbr_da = dst_addr;
+ desc->lld.mbr_ds = value;
+ desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV3
+ | AT_XDMAC_MBR_UBC_NDEN
+ | AT_XDMAC_MBR_UBC_NSEN
+ | ublen;
+ desc->lld.mbr_cfg = chan_cc;
+
+ dev_dbg(chan2dev(chan),
+ "%s: lld: mbr_da=%pad, mbr_ds=0x%08x, mbr_ubc=0x%08x, mbr_cfg=0x%08x\n",
+ __func__, &desc->lld.mbr_da, desc->lld.mbr_ds, desc->lld.mbr_ubc,
+ desc->lld.mbr_cfg);
+
+ return desc;
+}
+
+static struct dma_async_tx_descriptor *
+at_xdmac_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value,
+ size_t len, unsigned long flags)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ struct at_xdmac_desc *desc;
+
+ dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%zu, pattern=0x%x, flags=0x%lx\n",
+ __func__, &dest, len, value, flags);
+
+ if (unlikely(!len))
+ return NULL;
+
+ desc = at_xdmac_memset_create_desc(chan, atchan, dest, len, value);
+ list_add_tail(&desc->desc_node, &desc->descs_list);
+
+ desc->tx_dma_desc.cookie = -EBUSY;
+ desc->tx_dma_desc.flags = flags;
+ desc->xfer_size = len;
+
+ return &desc->tx_dma_desc;
+}
+
+static struct dma_async_tx_descriptor *
+at_xdmac_prep_dma_memset_sg(struct dma_chan *chan, struct scatterlist *sgl,
+ unsigned int sg_len, int value,
+ unsigned long flags)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ struct at_xdmac_desc *desc, *pdesc = NULL,
+ *ppdesc = NULL, *first = NULL;
+ struct scatterlist *sg, *psg = NULL, *ppsg = NULL;
+ size_t stride = 0, pstride = 0, len = 0;
+ int i;
+
+ if (!sgl)
+ return NULL;
+
+ dev_dbg(chan2dev(chan), "%s: sg_len=%d, value=0x%x, flags=0x%lx\n",
+ __func__, sg_len, value, flags);
+
+ /* Prepare descriptors. */
+ for_each_sg(sgl, sg, sg_len, i) {
+ dev_dbg(chan2dev(chan), "%s: dest=%pad, len=%d, pattern=0x%x, flags=0x%lx\n",
+ __func__, &sg_dma_address(sg), sg_dma_len(sg),
+ value, flags);
+ desc = at_xdmac_memset_create_desc(chan, atchan,
+ sg_dma_address(sg),
+ sg_dma_len(sg),
+ value);
+ if (!desc && first)
+ list_splice_tail_init(&first->descs_list,
+ &atchan->free_descs_list);
+
+ if (!first)
+ first = desc;
+
+ /* Update our strides */
+ pstride = stride;
+ if (psg)
+ stride = sg_dma_address(sg) -
+ (sg_dma_address(psg) + sg_dma_len(psg));
+
+ /*
+ * The scatterlist API gives us only the address and
+ * length of each elements.
+ *
+ * Unfortunately, we don't have the stride, which we
+ * will need to compute.
+ *
+ * That make us end up in a situation like this one:
+ * len stride len stride len
+ * +-------+ +-------+ +-------+
+ * | N-2 | | N-1 | | N |
+ * +-------+ +-------+ +-------+
+ *
+ * We need all these three elements (N-2, N-1 and N)
+ * to actually take the decision on whether we need to
+ * queue N-1 or reuse N-2.
+ *
+ * We will only consider N if it is the last element.
+ */
+ if (ppdesc && pdesc) {
+ if ((stride == pstride) &&
+ (sg_dma_len(ppsg) == sg_dma_len(psg))) {
+ dev_dbg(chan2dev(chan),
+ "%s: desc 0x%p can be merged with desc 0x%p\n",
+ __func__, pdesc, ppdesc);
+
+ /*
+ * Increment the block count of the
+ * N-2 descriptor
+ */
+ at_xdmac_increment_block_count(chan, ppdesc);
+ ppdesc->lld.mbr_dus = stride;
+
+ /*
+ * Put back the N-1 descriptor in the
+ * free descriptor list
+ */
+ list_add_tail(&pdesc->desc_node,
+ &atchan->free_descs_list);
+
+ /*
+ * Make our N-1 descriptor pointer
+ * point to the N-2 since they were
+ * actually merged.
+ */
+ pdesc = ppdesc;
+
+ /*
+ * Rule out the case where we don't have
+ * pstride computed yet (our second sg
+ * element)
+ *
+ * We also want to catch the case where there
+ * would be a negative stride,
+ */
+ } else if (pstride ||
+ sg_dma_address(sg) < sg_dma_address(psg)) {
+ /*
+ * Queue the N-1 descriptor after the
+ * N-2
+ */
+ at_xdmac_queue_desc(chan, ppdesc, pdesc);
+
+ /*
+ * Add the N-1 descriptor to the list
+ * of the descriptors used for this
+ * transfer
+ */
+ list_add_tail(&desc->desc_node,
+ &first->descs_list);
+ dev_dbg(chan2dev(chan),
+ "%s: add desc 0x%p to descs_list 0x%p\n",
+ __func__, desc, first);
+ }
+ }
+
+ /*
+ * If we are the last element, just see if we have the
+ * same size than the previous element.
+ *
+ * If so, we can merge it with the previous descriptor
+ * since we don't care about the stride anymore.
+ */
+ if ((i == (sg_len - 1)) &&
+ sg_dma_len(psg) == sg_dma_len(sg)) {
+ dev_dbg(chan2dev(chan),
+ "%s: desc 0x%p can be merged with desc 0x%p\n",
+ __func__, desc, pdesc);
+
+ /*
+ * Increment the block count of the N-1
+ * descriptor
+ */
+ at_xdmac_increment_block_count(chan, pdesc);
+ pdesc->lld.mbr_dus = stride;
+
+ /*
+ * Put back the N descriptor in the free
+ * descriptor list
+ */
+ list_add_tail(&desc->desc_node,
+ &atchan->free_descs_list);
+ }
+
+ /* Update our descriptors */
+ ppdesc = pdesc;
+ pdesc = desc;
+
+ /* Update our scatter pointers */
+ ppsg = psg;
+ psg = sg;
+
+ len += sg_dma_len(sg);
+ }
+
+ first->tx_dma_desc.cookie = -EBUSY;
+ first->tx_dma_desc.flags = flags;
+ first->xfer_size = len;
+
+ return &first->tx_dma_desc;
+}
+
+static enum dma_status
+at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
+ struct at_xdmac_desc *desc, *_desc, *iter;
+ struct list_head *descs_list;
+ enum dma_status ret;
+ int residue, retry;
+ u32 cur_nda, check_nda, cur_ubc, mask, value;
+ u8 dwidth = 0;
+ unsigned long flags;
+ bool initd;
+
+ ret = dma_cookie_status(chan, cookie, txstate);
+ if (ret == DMA_COMPLETE)
+ return ret;
+
+ if (!txstate)
+ return ret;
+
+ spin_lock_irqsave(&atchan->lock, flags);
+
+ desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node);
+
+ /*
+ * If the transfer has not been started yet, don't need to compute the
+ * residue, it's the transfer length.
+ */
+ if (!desc->active_xfer) {
+ dma_set_residue(txstate, desc->xfer_size);
+ goto spin_unlock;
+ }
+
+ residue = desc->xfer_size;
+ /*
+ * Flush FIFO: only relevant when the transfer is source peripheral
+ * synchronized. Flush is needed before reading CUBC because data in
+ * the FIFO are not reported by CUBC. Reporting a residue of the
+ * transfer length while we have data in FIFO can cause issue.
+ * Usecase: atmel USART has a timeout which means I have received
+ * characters but there is no more character received for a while. On
+ * timeout, it requests the residue. If the data are in the DMA FIFO,
+ * we will return a residue of the transfer length. It means no data
+ * received. If an application is waiting for these data, it will hang
+ * since we won't have another USART timeout without receiving new
+ * data.
+ */
+ mask = AT_XDMAC_CC_TYPE | AT_XDMAC_CC_DSYNC;
+ value = AT_XDMAC_CC_TYPE_PER_TRAN | AT_XDMAC_CC_DSYNC_PER2MEM;
+ if ((desc->lld.mbr_cfg & mask) == value) {
+ at_xdmac_write(atxdmac, AT_XDMAC_GSWF, atchan->mask);
+ while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS))
+ cpu_relax();
+ }
+
+ /*
+ * The easiest way to compute the residue should be to pause the DMA
+ * but doing this can lead to miss some data as some devices don't
+ * have FIFO.
+ * We need to read several registers because:
+ * - DMA is running therefore a descriptor change is possible while
+ * reading these registers
+ * - When the block transfer is done, the value of the CUBC register
+ * is set to its initial value until the fetch of the next descriptor.
+ * This value will corrupt the residue calculation so we have to skip
+ * it.
+ *
+ * INITD -------- ------------
+ * |____________________|
+ * _______________________ _______________
+ * NDA @desc2 \/ @desc3
+ * _______________________/\_______________
+ * __________ ___________ _______________
+ * CUBC 0 \/ MAX desc1 \/ MAX desc2
+ * __________/\___________/\_______________
+ *
+ * Since descriptors are aligned on 64 bits, we can assume that
+ * the update of NDA and CUBC is atomic.
+ * Memory barriers are used to ensure the read order of the registers.
+ * A max number of retries is set because unlikely it could never ends.
+ */
+ for (retry = 0; retry < AT_XDMAC_RESIDUE_MAX_RETRIES; retry++) {
+ check_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
+ rmb();
+ cur_ubc = at_xdmac_chan_read(atchan, AT_XDMAC_CUBC);
+ rmb();
+ initd = !!(at_xdmac_chan_read(atchan, AT_XDMAC_CC) & AT_XDMAC_CC_INITD);
+ rmb();
+ cur_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc;
+ rmb();
+
+ if ((check_nda == cur_nda) && initd)
+ break;
+ }
+
+ if (unlikely(retry >= AT_XDMAC_RESIDUE_MAX_RETRIES)) {
+ ret = DMA_ERROR;
+ goto spin_unlock;
+ }
+
+ /*
+ * Flush FIFO: only relevant when the transfer is source peripheral
+ * synchronized. Another flush is needed here because CUBC is updated
+ * when the controller sends the data write command. It can lead to
+ * report data that are not written in the memory or the device. The
+ * FIFO flush ensures that data are really written.
+ */
+ if ((desc->lld.mbr_cfg & mask) == value) {
+ at_xdmac_write(atxdmac, AT_XDMAC_GSWF, atchan->mask);
+ while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS))
+ cpu_relax();
+ }
+
+ /*
+ * Remove size of all microblocks already transferred and the current
+ * one. Then add the remaining size to transfer of the current
+ * microblock.
+ */
+ descs_list = &desc->descs_list;
+ list_for_each_entry_safe(iter, _desc, descs_list, desc_node) {
+ dwidth = at_xdmac_get_dwidth(iter->lld.mbr_cfg);
+ residue -= (iter->lld.mbr_ubc & 0xffffff) << dwidth;
+ if ((iter->lld.mbr_nda & 0xfffffffc) == cur_nda) {
+ desc = iter;
+ break;
+ }
+ }
+ residue += cur_ubc << dwidth;
+
+ dma_set_residue(txstate, residue);
+
+ dev_dbg(chan2dev(chan),
+ "%s: desc=0x%p, tx_dma_desc.phys=%pad, tx_status=%d, cookie=%d, residue=%d\n",
+ __func__, desc, &desc->tx_dma_desc.phys, ret, cookie, residue);
+
+spin_unlock:
+ spin_unlock_irqrestore(&atchan->lock, flags);
+ return ret;
+}
+
+static void at_xdmac_advance_work(struct at_xdmac_chan *atchan)
+{
+ struct at_xdmac_desc *desc;
+
+ /*
+ * If channel is enabled, do nothing, advance_work will be triggered
+ * after the interruption.
+ */
+ if (!at_xdmac_chan_is_enabled(atchan) && !list_empty(&atchan->xfers_list)) {
+ desc = list_first_entry(&atchan->xfers_list,
+ struct at_xdmac_desc,
+ xfer_node);
+ dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
+ if (!desc->active_xfer)
+ at_xdmac_start_xfer(atchan, desc);
+ }
+}
+
+static void at_xdmac_handle_cyclic(struct at_xdmac_chan *atchan)
+{
+ struct at_xdmac_desc *desc;
+ struct dma_async_tx_descriptor *txd;
+
+ spin_lock_irq(&atchan->lock);
+ if (list_empty(&atchan->xfers_list)) {
+ spin_unlock_irq(&atchan->lock);
+ return;
+ }
+ desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc,
+ xfer_node);
+ spin_unlock_irq(&atchan->lock);
+ txd = &desc->tx_dma_desc;
+ if (txd->flags & DMA_PREP_INTERRUPT)
+ dmaengine_desc_get_callback_invoke(txd, NULL);
+}
+
+static void at_xdmac_handle_error(struct at_xdmac_chan *atchan)
+{
+ struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
+ struct at_xdmac_desc *bad_desc;
+
+ /*
+ * The descriptor currently at the head of the active list is
+ * broken. Since we don't have any way to report errors, we'll
+ * just have to scream loudly and try to continue with other
+ * descriptors queued (if any).
+ */
+ if (atchan->irq_status & AT_XDMAC_CIS_RBEIS)
+ dev_err(chan2dev(&atchan->chan), "read bus error!!!");
+ if (atchan->irq_status & AT_XDMAC_CIS_WBEIS)
+ dev_err(chan2dev(&atchan->chan), "write bus error!!!");
+ if (atchan->irq_status & AT_XDMAC_CIS_ROIS)
+ dev_err(chan2dev(&atchan->chan), "request overflow error!!!");
+
+ spin_lock_irq(&atchan->lock);
+
+ /* Channel must be disabled first as it's not done automatically */
+ at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
+ while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
+ cpu_relax();
+
+ bad_desc = list_first_entry(&atchan->xfers_list,
+ struct at_xdmac_desc,
+ xfer_node);
+
+ spin_unlock_irq(&atchan->lock);
+
+ /* Print bad descriptor's details if needed */
+ dev_dbg(chan2dev(&atchan->chan),
+ "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
+ __func__, &bad_desc->lld.mbr_sa, &bad_desc->lld.mbr_da,
+ bad_desc->lld.mbr_ubc);
+
+ /* Then continue with usual descriptor management */
+}
+
+static void at_xdmac_tasklet(struct tasklet_struct *t)
+{
+ struct at_xdmac_chan *atchan = from_tasklet(atchan, t, tasklet);
+ struct at_xdmac_desc *desc;
+ u32 error_mask;
+
+ dev_dbg(chan2dev(&atchan->chan), "%s: status=0x%08x\n",
+ __func__, atchan->irq_status);
+
+ error_mask = AT_XDMAC_CIS_RBEIS
+ | AT_XDMAC_CIS_WBEIS
+ | AT_XDMAC_CIS_ROIS;
+
+ if (at_xdmac_chan_is_cyclic(atchan)) {
+ at_xdmac_handle_cyclic(atchan);
+ } else if ((atchan->irq_status & AT_XDMAC_CIS_LIS)
+ || (atchan->irq_status & error_mask)) {
+ struct dma_async_tx_descriptor *txd;
+
+ if (atchan->irq_status & error_mask)
+ at_xdmac_handle_error(atchan);
+
+ spin_lock_irq(&atchan->lock);
+ desc = list_first_entry(&atchan->xfers_list,
+ struct at_xdmac_desc,
+ xfer_node);
+ dev_vdbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc);
+ if (!desc->active_xfer) {
+ dev_err(chan2dev(&atchan->chan), "Xfer not active: exiting");
+ spin_unlock_irq(&atchan->lock);
+ return;
+ }
+
+ txd = &desc->tx_dma_desc;
+ dma_cookie_complete(txd);
+ /* Remove the transfer from the transfer list. */
+ list_del(&desc->xfer_node);
+ spin_unlock_irq(&atchan->lock);
+
+ if (txd->flags & DMA_PREP_INTERRUPT)
+ dmaengine_desc_get_callback_invoke(txd, NULL);
+
+ dma_run_dependencies(txd);
+
+ spin_lock_irq(&atchan->lock);
+ /* Move the xfer descriptors into the free descriptors list. */
+ list_splice_tail_init(&desc->descs_list,
+ &atchan->free_descs_list);
+ at_xdmac_advance_work(atchan);
+ spin_unlock_irq(&atchan->lock);
+ }
+}
+
+static irqreturn_t at_xdmac_interrupt(int irq, void *dev_id)
+{
+ struct at_xdmac *atxdmac = (struct at_xdmac *)dev_id;
+ struct at_xdmac_chan *atchan;
+ u32 imr, status, pending;
+ u32 chan_imr, chan_status;
+ int i, ret = IRQ_NONE;
+
+ do {
+ imr = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
+ status = at_xdmac_read(atxdmac, AT_XDMAC_GIS);
+ pending = status & imr;
+
+ dev_vdbg(atxdmac->dma.dev,
+ "%s: status=0x%08x, imr=0x%08x, pending=0x%08x\n",
+ __func__, status, imr, pending);
+
+ if (!pending)
+ break;
+
+ /* We have to find which channel has generated the interrupt. */
+ for (i = 0; i < atxdmac->dma.chancnt; i++) {
+ if (!((1 << i) & pending))
+ continue;
+
+ atchan = &atxdmac->chan[i];
+ chan_imr = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
+ chan_status = at_xdmac_chan_read(atchan, AT_XDMAC_CIS);
+ atchan->irq_status = chan_status & chan_imr;
+ dev_vdbg(atxdmac->dma.dev,
+ "%s: chan%d: imr=0x%x, status=0x%x\n",
+ __func__, i, chan_imr, chan_status);
+ dev_vdbg(chan2dev(&atchan->chan),
+ "%s: CC=0x%08x CNDA=0x%08x, CNDC=0x%08x, CSA=0x%08x, CDA=0x%08x, CUBC=0x%08x\n",
+ __func__,
+ at_xdmac_chan_read(atchan, AT_XDMAC_CC),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CNDA),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CNDC),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CSA),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CDA),
+ at_xdmac_chan_read(atchan, AT_XDMAC_CUBC));
+
+ if (atchan->irq_status & (AT_XDMAC_CIS_RBEIS | AT_XDMAC_CIS_WBEIS))
+ at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
+
+ tasklet_schedule(&atchan->tasklet);
+ ret = IRQ_HANDLED;
+ }
+
+ } while (pending);
+
+ return ret;
+}
+
+static void at_xdmac_issue_pending(struct dma_chan *chan)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ unsigned long flags;
+
+ dev_dbg(chan2dev(&atchan->chan), "%s\n", __func__);
+
+ spin_lock_irqsave(&atchan->lock, flags);
+ at_xdmac_advance_work(atchan);
+ spin_unlock_irqrestore(&atchan->lock, flags);
+
+ return;
+}
+
+static int at_xdmac_device_config(struct dma_chan *chan,
+ struct dma_slave_config *config)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ int ret;
+ unsigned long flags;
+
+ dev_dbg(chan2dev(chan), "%s\n", __func__);
+
+ spin_lock_irqsave(&atchan->lock, flags);
+ ret = at_xdmac_set_slave_config(chan, config);
+ spin_unlock_irqrestore(&atchan->lock, flags);
+
+ return ret;
+}
+
+static int at_xdmac_device_pause(struct dma_chan *chan)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
+ unsigned long flags;
+
+ dev_dbg(chan2dev(chan), "%s\n", __func__);
+
+ if (test_and_set_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status))
+ return 0;
+
+ spin_lock_irqsave(&atchan->lock, flags);
+ at_xdmac_write(atxdmac, AT_XDMAC_GRWS, atchan->mask);
+ while (at_xdmac_chan_read(atchan, AT_XDMAC_CC)
+ & (AT_XDMAC_CC_WRIP | AT_XDMAC_CC_RDIP))
+ cpu_relax();
+ spin_unlock_irqrestore(&atchan->lock, flags);
+
+ return 0;
+}
+
+static int at_xdmac_device_resume(struct dma_chan *chan)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
+ unsigned long flags;
+
+ dev_dbg(chan2dev(chan), "%s\n", __func__);
+
+ spin_lock_irqsave(&atchan->lock, flags);
+ if (!at_xdmac_chan_is_paused(atchan)) {
+ spin_unlock_irqrestore(&atchan->lock, flags);
+ return 0;
+ }
+
+ at_xdmac_write(atxdmac, AT_XDMAC_GRWR, atchan->mask);
+ clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
+ spin_unlock_irqrestore(&atchan->lock, flags);
+
+ return 0;
+}
+
+static int at_xdmac_device_terminate_all(struct dma_chan *chan)
+{
+ struct at_xdmac_desc *desc, *_desc;
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ struct at_xdmac *atxdmac = to_at_xdmac(atchan->chan.device);
+ unsigned long flags;
+
+ dev_dbg(chan2dev(chan), "%s\n", __func__);
+
+ spin_lock_irqsave(&atchan->lock, flags);
+ at_xdmac_write(atxdmac, AT_XDMAC_GD, atchan->mask);
+ while (at_xdmac_read(atxdmac, AT_XDMAC_GS) & atchan->mask)
+ cpu_relax();
+
+ /* Cancel all pending transfers. */
+ list_for_each_entry_safe(desc, _desc, &atchan->xfers_list, xfer_node) {
+ list_del(&desc->xfer_node);
+ list_splice_tail_init(&desc->descs_list,
+ &atchan->free_descs_list);
+ }
+
+ clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status);
+ clear_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status);
+ spin_unlock_irqrestore(&atchan->lock, flags);
+
+ return 0;
+}
+
+static int at_xdmac_alloc_chan_resources(struct dma_chan *chan)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ struct at_xdmac_desc *desc;
+ int i;
+
+ if (at_xdmac_chan_is_enabled(atchan)) {
+ dev_err(chan2dev(chan),
+ "can't allocate channel resources (channel enabled)\n");
+ return -EIO;
+ }
+
+ if (!list_empty(&atchan->free_descs_list)) {
+ dev_err(chan2dev(chan),
+ "can't allocate channel resources (channel not free from a previous use)\n");
+ return -EIO;
+ }
+
+ for (i = 0; i < init_nr_desc_per_channel; i++) {
+ desc = at_xdmac_alloc_desc(chan, GFP_KERNEL);
+ if (!desc) {
+ if (i == 0) {
+ dev_warn(chan2dev(chan),
+ "can't allocate any descriptors\n");
+ return -EIO;
+ }
+ dev_warn(chan2dev(chan),
+ "only %d descriptors have been allocated\n", i);
+ break;
+ }
+ list_add_tail(&desc->desc_node, &atchan->free_descs_list);
+ }
+
+ dma_cookie_init(chan);
+
+ dev_dbg(chan2dev(chan), "%s: allocated %d descriptors\n", __func__, i);
+
+ return i;
+}
+
+static void at_xdmac_free_chan_resources(struct dma_chan *chan)
+{
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+ struct at_xdmac *atxdmac = to_at_xdmac(chan->device);
+ struct at_xdmac_desc *desc, *_desc;
+
+ list_for_each_entry_safe(desc, _desc, &atchan->free_descs_list, desc_node) {
+ dev_dbg(chan2dev(chan), "%s: freeing descriptor %p\n", __func__, desc);
+ list_del(&desc->desc_node);
+ dma_pool_free(atxdmac->at_xdmac_desc_pool, desc, desc->tx_dma_desc.phys);
+ }
+
+ return;
+}
+
+#ifdef CONFIG_PM
+static int atmel_xdmac_prepare(struct device *dev)
+{
+ struct at_xdmac *atxdmac = dev_get_drvdata(dev);
+ struct dma_chan *chan, *_chan;
+
+ list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+
+ /* Wait for transfer completion, except in cyclic case. */
+ if (at_xdmac_chan_is_enabled(atchan) && !at_xdmac_chan_is_cyclic(atchan))
+ return -EAGAIN;
+ }
+ return 0;
+}
+#else
+# define atmel_xdmac_prepare NULL
+#endif
+
+#ifdef CONFIG_PM_SLEEP
+static int atmel_xdmac_suspend(struct device *dev)
+{
+ struct at_xdmac *atxdmac = dev_get_drvdata(dev);
+ struct dma_chan *chan, *_chan;
+
+ list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
+ struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
+
+ atchan->save_cc = at_xdmac_chan_read(atchan, AT_XDMAC_CC);
+ if (at_xdmac_chan_is_cyclic(atchan)) {
+ if (!at_xdmac_chan_is_paused(atchan))
+ at_xdmac_device_pause(chan);
+ atchan->save_cim = at_xdmac_chan_read(atchan, AT_XDMAC_CIM);
+ atchan->save_cnda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA);
+ atchan->save_cndc = at_xdmac_chan_read(atchan, AT_XDMAC_CNDC);
+ }
+ }
+ atxdmac->save_gim = at_xdmac_read(atxdmac, AT_XDMAC_GIM);
+ atxdmac->save_gs = at_xdmac_read(atxdmac, AT_XDMAC_GS);
+
+ at_xdmac_off(atxdmac);
+ clk_disable_unprepare(atxdmac->clk);
+ return 0;
+}
+
+static int atmel_xdmac_resume(struct device *dev)
+{
+ struct at_xdmac *atxdmac = dev_get_drvdata(dev);
+ struct at_xdmac_chan *atchan;
+ struct dma_chan *chan, *_chan;
+ int i;
+ int ret;
+
+ ret = clk_prepare_enable(atxdmac->clk);
+ if (ret)
+ return ret;
+
+ /* Clear pending interrupts. */
+ for (i = 0; i < atxdmac->dma.chancnt; i++) {
+ atchan = &atxdmac->chan[i];
+ while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
+ cpu_relax();
+ }
+
+ at_xdmac_write(atxdmac, AT_XDMAC_GIE, atxdmac->save_gim);
+ list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
+ atchan = to_at_xdmac_chan(chan);
+ at_xdmac_chan_write(atchan, AT_XDMAC_CC, atchan->save_cc);
+ if (at_xdmac_chan_is_cyclic(atchan)) {
+ if (at_xdmac_chan_is_paused(atchan))
+ at_xdmac_device_resume(chan);
+ at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, atchan->save_cnda);
+ at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, atchan->save_cndc);
+ at_xdmac_chan_write(atchan, AT_XDMAC_CIE, atchan->save_cim);
+ wmb();
+ if (atxdmac->save_gs & atchan->mask)
+ at_xdmac_write(atxdmac, AT_XDMAC_GE, atchan->mask);
+ }
+ }
+ return 0;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static int at_xdmac_probe(struct platform_device *pdev)
+{
+ struct at_xdmac *atxdmac;
+ int irq, size, nr_channels, i, ret;
+ void __iomem *base;
+ u32 reg;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ /*
+ * Read number of xdmac channels, read helper function can't be used
+ * since atxdmac is not yet allocated and we need to know the number
+ * of channels to do the allocation.
+ */
+ reg = readl_relaxed(base + AT_XDMAC_GTYPE);
+ nr_channels = AT_XDMAC_NB_CH(reg);
+ if (nr_channels > AT_XDMAC_MAX_CHAN) {
+ dev_err(&pdev->dev, "invalid number of channels (%u)\n",
+ nr_channels);
+ return -EINVAL;
+ }
+
+ size = sizeof(*atxdmac);
+ size += nr_channels * sizeof(struct at_xdmac_chan);
+ atxdmac = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
+ if (!atxdmac) {
+ dev_err(&pdev->dev, "can't allocate at_xdmac structure\n");
+ return -ENOMEM;
+ }
+
+ atxdmac->regs = base;
+ atxdmac->irq = irq;
+
+ atxdmac->clk = devm_clk_get(&pdev->dev, "dma_clk");
+ if (IS_ERR(atxdmac->clk)) {
+ dev_err(&pdev->dev, "can't get dma_clk\n");
+ return PTR_ERR(atxdmac->clk);
+ }
+
+ /* Do not use dev res to prevent races with tasklet */
+ ret = request_irq(atxdmac->irq, at_xdmac_interrupt, 0, "at_xdmac", atxdmac);
+ if (ret) {
+ dev_err(&pdev->dev, "can't request irq\n");
+ return ret;
+ }
+
+ ret = clk_prepare_enable(atxdmac->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "can't prepare or enable clock\n");
+ goto err_free_irq;
+ }
+
+ atxdmac->at_xdmac_desc_pool =
+ dmam_pool_create(dev_name(&pdev->dev), &pdev->dev,
+ sizeof(struct at_xdmac_desc), 4, 0);
+ if (!atxdmac->at_xdmac_desc_pool) {
+ dev_err(&pdev->dev, "no memory for descriptors dma pool\n");
+ ret = -ENOMEM;
+ goto err_clk_disable;
+ }
+
+ dma_cap_set(DMA_CYCLIC, atxdmac->dma.cap_mask);
+ dma_cap_set(DMA_INTERLEAVE, atxdmac->dma.cap_mask);
+ dma_cap_set(DMA_MEMCPY, atxdmac->dma.cap_mask);
+ dma_cap_set(DMA_MEMSET, atxdmac->dma.cap_mask);
+ dma_cap_set(DMA_MEMSET_SG, atxdmac->dma.cap_mask);
+ dma_cap_set(DMA_SLAVE, atxdmac->dma.cap_mask);
+ /*
+ * Without DMA_PRIVATE the driver is not able to allocate more than
+ * one channel, second allocation fails in private_candidate.
+ */
+ dma_cap_set(DMA_PRIVATE, atxdmac->dma.cap_mask);
+ atxdmac->dma.dev = &pdev->dev;
+ atxdmac->dma.device_alloc_chan_resources = at_xdmac_alloc_chan_resources;
+ atxdmac->dma.device_free_chan_resources = at_xdmac_free_chan_resources;
+ atxdmac->dma.device_tx_status = at_xdmac_tx_status;
+ atxdmac->dma.device_issue_pending = at_xdmac_issue_pending;
+ atxdmac->dma.device_prep_dma_cyclic = at_xdmac_prep_dma_cyclic;
+ atxdmac->dma.device_prep_interleaved_dma = at_xdmac_prep_interleaved;
+ atxdmac->dma.device_prep_dma_memcpy = at_xdmac_prep_dma_memcpy;
+ atxdmac->dma.device_prep_dma_memset = at_xdmac_prep_dma_memset;
+ atxdmac->dma.device_prep_dma_memset_sg = at_xdmac_prep_dma_memset_sg;
+ atxdmac->dma.device_prep_slave_sg = at_xdmac_prep_slave_sg;
+ atxdmac->dma.device_config = at_xdmac_device_config;
+ atxdmac->dma.device_pause = at_xdmac_device_pause;
+ atxdmac->dma.device_resume = at_xdmac_device_resume;
+ atxdmac->dma.device_terminate_all = at_xdmac_device_terminate_all;
+ atxdmac->dma.src_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
+ atxdmac->dma.dst_addr_widths = AT_XDMAC_DMA_BUSWIDTHS;
+ atxdmac->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
+ atxdmac->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
+
+ /* Disable all chans and interrupts. */
+ at_xdmac_off(atxdmac);
+
+ /* Init channels. */
+ INIT_LIST_HEAD(&atxdmac->dma.channels);
+ for (i = 0; i < nr_channels; i++) {
+ struct at_xdmac_chan *atchan = &atxdmac->chan[i];
+
+ atchan->chan.device = &atxdmac->dma;
+ list_add_tail(&atchan->chan.device_node,
+ &atxdmac->dma.channels);
+
+ atchan->ch_regs = at_xdmac_chan_reg_base(atxdmac, i);
+ atchan->mask = 1 << i;
+
+ spin_lock_init(&atchan->lock);
+ INIT_LIST_HEAD(&atchan->xfers_list);
+ INIT_LIST_HEAD(&atchan->free_descs_list);
+ tasklet_setup(&atchan->tasklet, at_xdmac_tasklet);
+
+ /* Clear pending interrupts. */
+ while (at_xdmac_chan_read(atchan, AT_XDMAC_CIS))
+ cpu_relax();
+ }
+ platform_set_drvdata(pdev, atxdmac);
+
+ ret = dma_async_device_register(&atxdmac->dma);
+ if (ret) {
+ dev_err(&pdev->dev, "fail to register DMA engine device\n");
+ goto err_clk_disable;
+ }
+
+ ret = of_dma_controller_register(pdev->dev.of_node,
+ at_xdmac_xlate, atxdmac);
+ if (ret) {
+ dev_err(&pdev->dev, "could not register of dma controller\n");
+ goto err_dma_unregister;
+ }
+
+ dev_info(&pdev->dev, "%d channels, mapped at 0x%p\n",
+ nr_channels, atxdmac->regs);
+
+ return 0;
+
+err_dma_unregister:
+ dma_async_device_unregister(&atxdmac->dma);
+err_clk_disable:
+ clk_disable_unprepare(atxdmac->clk);
+err_free_irq:
+ free_irq(atxdmac->irq, atxdmac);
+ return ret;
+}
+
+static int at_xdmac_remove(struct platform_device *pdev)
+{
+ struct at_xdmac *atxdmac = (struct at_xdmac *)platform_get_drvdata(pdev);
+ int i;
+
+ at_xdmac_off(atxdmac);
+ of_dma_controller_free(pdev->dev.of_node);
+ dma_async_device_unregister(&atxdmac->dma);
+ clk_disable_unprepare(atxdmac->clk);
+
+ free_irq(atxdmac->irq, atxdmac);
+
+ for (i = 0; i < atxdmac->dma.chancnt; i++) {
+ struct at_xdmac_chan *atchan = &atxdmac->chan[i];
+
+ tasklet_kill(&atchan->tasklet);
+ at_xdmac_free_chan_resources(&atchan->chan);
+ }
+
+ return 0;
+}
+
+static const struct dev_pm_ops atmel_xdmac_dev_pm_ops = {
+ .prepare = atmel_xdmac_prepare,
+ SET_LATE_SYSTEM_SLEEP_PM_OPS(atmel_xdmac_suspend, atmel_xdmac_resume)
+};
+
+static const struct of_device_id atmel_xdmac_dt_ids[] = {
+ {
+ .compatible = "atmel,sama5d4-dma",
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(of, atmel_xdmac_dt_ids);
+
+static struct platform_driver at_xdmac_driver = {
+ .probe = at_xdmac_probe,
+ .remove = at_xdmac_remove,
+ .driver = {
+ .name = "at_xdmac",
+ .of_match_table = of_match_ptr(atmel_xdmac_dt_ids),
+ .pm = &atmel_xdmac_dev_pm_ops,
+ }
+};
+
+static int __init at_xdmac_init(void)
+{
+ return platform_driver_probe(&at_xdmac_driver, at_xdmac_probe);
+}
+subsys_initcall(at_xdmac_init);
+
+MODULE_DESCRIPTION("Atmel Extended DMA Controller driver");
+MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>");
+MODULE_LICENSE("GPL");