/* * Driver for the Atmel Extensible DMA Controller (aka XDMAC on AT91 systems) * * Copyright (C) 2014 Atmel Corporation * * Author: Ludovic Desroches * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published by * the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along with * this program. If not, see . */ #include #include #include #include #include #include #include #include #include #include #include #include #include #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_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 & (h) << 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 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[3]; /* Channel Configuration Register */ #define AT_XDMAC_CUR_CFG 0 /* Current channel conf */ #define AT_XDMAC_DEV_TO_MEM_CFG 1 /* Predifined dev to mem channel conf */ #define AT_XDMAC_MEM_TO_DEV_CFG 2 /* Predifined mem to dev channel conf */ u8 perid; /* Peripheral ID */ u8 perif; /* Peripheral Interface */ u8 memif; /* Memory Interface */ u32 per_src_addr; u32 per_dst_addr; u32 save_cim; u32 save_cnda; u32 save_cndc; unsigned long status; struct tasklet_struct tasklet; 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[0]; }; /* ----- Descriptors ----- */ /* Linked List Descriptor */ struct at_xdmac_lld { dma_addr_t mbr_nda; /* Next Descriptor Member */ u32 mbr_ubc; /* Microblock Control Member */ dma_addr_t mbr_sa; /* Source Address Member */ dma_addr_t mbr_da; /* Destination Address Member */ u32 mbr_cfg; /* Configuration Register */ }; 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; }; 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 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); if (at_xdmac_chan_is_enabled(atchan)) return; /* 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 memory to memory 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 (is_slave_direction(first->direction)) { reg = AT_XDMAC_CNDC_NDVIEW_NDV1; if (first->direction == DMA_MEM_TO_DEV) atchan->cfg[AT_XDMAC_CUR_CFG] = atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG]; else atchan->cfg[AT_XDMAC_CUR_CFG] = atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG]; at_xdmac_chan_write(atchan, AT_XDMAC_CC, atchan->cfg[AT_XDMAC_CUR_CFG]); } else { /* * No need to write AT_XDMAC_CC reg, it will be done when the * descriptor is fecthed. */ reg = AT_XDMAC_CNDC_NDVIEW_NDV2; } 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 | 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; spin_lock_bh(&atchan->lock); cookie = dma_cookie_assign(tx); dev_vdbg(chan2dev(tx->chan), "%s: atchan 0x%p, add desc 0x%p to xfers_list\n", __func__, atchan, desc); list_add_tail(&desc->xfer_node, &atchan->xfers_list); if (list_is_singular(&atchan->xfers_list)) at_xdmac_start_xfer(atchan, desc); spin_unlock_bh(&atchan->lock); 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_alloc(atxdmac->at_xdmac_desc_pool, gfp_flags, &phys); if (desc) { memset(desc, 0, sizeof(*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; } /* 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); desc->active_xfer = false; } return 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_set_slave_config(struct dma_chan *chan, struct dma_slave_config *sconfig) { struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); u8 dwidth; int csize; atchan->cfg[AT_XDMAC_DEV_TO_MEM_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 = at_xdmac_csize(sconfig->src_maxburst); if (csize < 0) { dev_err(chan2dev(chan), "invalid src maxburst value\n"); return -EINVAL; } atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG] |= AT_XDMAC_CC_CSIZE(csize); dwidth = ffs(sconfig->src_addr_width) - 1; atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG] |= AT_XDMAC_CC_DWIDTH(dwidth); atchan->cfg[AT_XDMAC_MEM_TO_DEV_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 = at_xdmac_csize(sconfig->dst_maxburst); if (csize < 0) { dev_err(chan2dev(chan), "invalid src maxburst value\n"); return -EINVAL; } atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG] |= AT_XDMAC_CC_CSIZE(csize); dwidth = ffs(sconfig->dst_addr_width) - 1; atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG] |= AT_XDMAC_CC_DWIDTH(dwidth); /* Src and dst addr are needed to configure the link list descriptor. */ atchan->per_src_addr = sconfig->src_addr; atchan->per_dst_addr = sconfig->dst_addr; dev_dbg(chan2dev(chan), "%s: cfg[dev2mem]=0x%08x, cfg[mem2dev]=0x%08x, per_src_addr=0x%08x, per_dst_addr=0x%08x\n", __func__, atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG], atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG], atchan->per_src_addr, atchan->per_dst_addr); 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; u32 cfg; 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_bh(&atchan->lock); /* Prepare descriptors. */ for_each_sg(sgl, sg, sg_len, i) { struct at_xdmac_desc *desc = NULL; u32 len, mem; len = sg_dma_len(sg); mem = sg_dma_address(sg); if (unlikely(!len)) { dev_err(chan2dev(chan), "sg data length is zero\n"); spin_unlock_bh(&atchan->lock); return NULL; } 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_init(&first->descs_list, &atchan->free_descs_list); spin_unlock_bh(&atchan->lock); return NULL; } /* Linked list descriptor setup. */ if (direction == DMA_DEV_TO_MEM) { desc->lld.mbr_sa = atchan->per_src_addr; desc->lld.mbr_da = mem; cfg = atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG]; } else { desc->lld.mbr_sa = mem; desc->lld.mbr_da = atchan->per_dst_addr; cfg = atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG]; } desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV1 /* next descriptor view */ | AT_XDMAC_MBR_UBC_NDEN /* next descriptor dst parameter update */ | AT_XDMAC_MBR_UBC_NSEN /* next descriptor src parameter update */ | (i == sg_len - 1 ? 0 : AT_XDMAC_MBR_UBC_NDE) /* descriptor fetch */ | len / (1 << at_xdmac_get_dwidth(cfg)); /* microblock length */ dev_dbg(chan2dev(chan), "%s: lld: mbr_sa=0x%08x, mbr_da=0x%08x, mbr_ubc=0x%08x\n", __func__, desc->lld.mbr_sa, desc->lld.mbr_da, desc->lld.mbr_ubc); /* Chain lld. */ if (prev) { prev->lld.mbr_nda = desc->tx_dma_desc.phys; dev_dbg(chan2dev(chan), "%s: chain lld: prev=0x%p, mbr_nda=0x%08x\n", __func__, prev, prev->lld.mbr_nda); } 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); } spin_unlock_bh(&atchan->lock); first->tx_dma_desc.flags = flags; first->xfer_size = sg_len; first->direction = direction; return &first->tx_dma_desc; } 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; u32 cfg; dev_dbg(chan2dev(chan), "%s: buf_addr=0x%08x, buf_len=%d, period_len=%d, 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; } for (i = 0; i < periods; i++) { struct at_xdmac_desc *desc = NULL; spin_lock_bh(&atchan->lock); desc = at_xdmac_get_desc(atchan); if (!desc) { dev_err(chan2dev(chan), "can't get descriptor\n"); if (first) list_splice_init(&first->descs_list, &atchan->free_descs_list); spin_unlock_bh(&atchan->lock); return NULL; } spin_unlock_bh(&atchan->lock); dev_dbg(chan2dev(chan), "%s: desc=0x%p, tx_dma_desc.phys=0x%08x\n", __func__, desc, desc->tx_dma_desc.phys); if (direction == DMA_DEV_TO_MEM) { desc->lld.mbr_sa = atchan->per_src_addr; desc->lld.mbr_da = buf_addr + i * period_len; cfg = atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG]; } else { desc->lld.mbr_sa = buf_addr + i * period_len; desc->lld.mbr_da = atchan->per_dst_addr; cfg = atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG]; }; desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV1 | AT_XDMAC_MBR_UBC_NDEN | AT_XDMAC_MBR_UBC_NSEN | AT_XDMAC_MBR_UBC_NDE | period_len >> at_xdmac_get_dwidth(cfg); dev_dbg(chan2dev(chan), "%s: lld: mbr_sa=0x%08x, mbr_da=0x%08x, mbr_ubc=0x%08x\n", __func__, desc->lld.mbr_sa, desc->lld.mbr_da, desc->lld.mbr_ubc); /* Chain lld. */ if (prev) { prev->lld.mbr_nda = desc->tx_dma_desc.phys; dev_dbg(chan2dev(chan), "%s: chain lld: prev=0x%p, mbr_nda=0x%08x\n", __func__, prev, prev->lld.mbr_nda); } 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); } prev->lld.mbr_nda = first->tx_dma_desc.phys; dev_dbg(chan2dev(chan), "%s: chain lld: prev=0x%p, mbr_nda=0x%08x\n", __func__, prev, prev->lld.mbr_nda); first->tx_dma_desc.flags = flags; first->xfer_size = buf_len; first->direction = direction; 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. */ u32 chan_cc = 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; dev_dbg(chan2dev(chan), "%s: src=0x%08x, dest=0x%08x, len=%d, flags=0x%lx\n", __func__, src, dest, len, flags); if (unlikely(!len)) return NULL; /* * 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 (!((src_addr | dst_addr) & 7)) { dwidth = AT_XDMAC_CC_DWIDTH_DWORD; dev_dbg(chan2dev(chan), "%s: dwidth: double word\n", __func__); } else if (!((src_addr | dst_addr) & 3)) { dwidth = AT_XDMAC_CC_DWIDTH_WORD; dev_dbg(chan2dev(chan), "%s: dwidth: word\n", __func__); } else if (!((src_addr | dst_addr) & 1)) { dwidth = AT_XDMAC_CC_DWIDTH_HALFWORD; dev_dbg(chan2dev(chan), "%s: dwidth: half word\n", __func__); } else { dwidth = AT_XDMAC_CC_DWIDTH_BYTE; dev_dbg(chan2dev(chan), "%s: dwidth: byte\n", __func__); } /* Prepare descriptors. */ while (remaining_size) { struct at_xdmac_desc *desc = NULL; dev_dbg(chan2dev(chan), "%s: remaining_size=%u\n", __func__, remaining_size); spin_lock_bh(&atchan->lock); desc = at_xdmac_get_desc(atchan); spin_unlock_bh(&atchan->lock); if (!desc) { dev_err(chan2dev(chan), "can't get descriptor\n"); if (first) list_splice_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=%u\n", __func__, xfer_size); /* Check remaining length and change data width if needed. */ if (!((src_addr | dst_addr | xfer_size) & 7)) { dwidth = AT_XDMAC_CC_DWIDTH_DWORD; dev_dbg(chan2dev(chan), "%s: dwidth: double word\n", __func__); } else if (!((src_addr | dst_addr | xfer_size) & 3)) { dwidth = AT_XDMAC_CC_DWIDTH_WORD; dev_dbg(chan2dev(chan), "%s: dwidth: word\n", __func__); } else if (!((src_addr | dst_addr | xfer_size) & 1)) { dwidth = AT_XDMAC_CC_DWIDTH_HALFWORD; dev_dbg(chan2dev(chan), "%s: dwidth: half word\n", __func__); } else if ((src_addr | dst_addr | xfer_size) & 1) { dwidth = AT_XDMAC_CC_DWIDTH_BYTE; dev_dbg(chan2dev(chan), "%s: dwidth: byte\n", __func__); } 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 | (remaining_size ? AT_XDMAC_MBR_UBC_NDE : 0) | ublen; desc->lld.mbr_cfg = chan_cc; dev_dbg(chan2dev(chan), "%s: lld: mbr_sa=0x%08x, mbr_da=0x%08x, 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) { prev->lld.mbr_nda = desc->tx_dma_desc.phys; dev_dbg(chan2dev(chan), "%s: chain lld: prev=0x%p, mbr_nda=0x%08x\n", __func__, prev, prev->lld.mbr_nda); } 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 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; struct list_head *descs_list; enum dma_status ret; int residue; u32 cur_nda; u8 dwidth = at_xdmac_get_dwidth(atchan->cfg[AT_XDMAC_CUR_CFG]); ret = dma_cookie_status(chan, cookie, txstate); if (ret == DMA_COMPLETE) return ret; if (!txstate) return ret; spin_lock_bh(&atchan->lock); 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); return ret; } residue = desc->xfer_size; /* Flush FIFO. */ at_xdmac_write(atxdmac, AT_XDMAC_GSWF, atchan->mask); while (!(at_xdmac_chan_read(atchan, AT_XDMAC_CIS) & AT_XDMAC_CIS_FIS)) cpu_relax(); cur_nda = at_xdmac_chan_read(atchan, AT_XDMAC_CNDA) & 0xfffffffc; /* * 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(desc, _desc, descs_list, desc_node) { residue -= (desc->lld.mbr_ubc & 0xffffff) << dwidth; if ((desc->lld.mbr_nda & 0xfffffffc) == cur_nda) break; } residue += at_xdmac_chan_read(atchan, AT_XDMAC_CUBC) << dwidth; spin_unlock_bh(&atchan->lock); dma_set_residue(txstate, residue); dev_dbg(chan2dev(chan), "%s: desc=0x%p, tx_dma_desc.phys=0x%08x, tx_status=%d, cookie=%d, residue=%d\n", __func__, desc, desc->tx_dma_desc.phys, ret, cookie, residue); return ret; } /* Call must be protected by lock. */ static void at_xdmac_remove_xfer(struct at_xdmac_chan *atchan, struct at_xdmac_desc *desc) { dev_dbg(chan2dev(&atchan->chan), "%s: desc 0x%p\n", __func__, desc); /* * Remove the transfer from the transfer list then move the transfer * descriptors into the free descriptors list. */ list_del(&desc->xfer_node); list_splice_init(&desc->descs_list, &atchan->free_descs_list); } static void at_xdmac_advance_work(struct at_xdmac_chan *atchan) { struct at_xdmac_desc *desc; spin_lock_bh(&atchan->lock); /* * 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); } spin_unlock_bh(&atchan->lock); } static void at_xdmac_handle_cyclic(struct at_xdmac_chan *atchan) { struct at_xdmac_desc *desc; struct dma_async_tx_descriptor *txd; desc = list_first_entry(&atchan->xfers_list, struct at_xdmac_desc, xfer_node); txd = &desc->tx_dma_desc; if (txd->callback && (txd->flags & DMA_PREP_INTERRUPT)) txd->callback(txd->callback_param); } static void at_xdmac_tasklet(unsigned long data) { struct at_xdmac_chan *atchan = (struct at_xdmac_chan *)data; struct at_xdmac_desc *desc; u32 error_mask; dev_dbg(chan2dev(&atchan->chan), "%s: status=0x%08lx\n", __func__, atchan->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->status & AT_XDMAC_CIS_LIS) || (atchan->status & error_mask)) { struct dma_async_tx_descriptor *txd; if (atchan->status & AT_XDMAC_CIS_RBEIS) dev_err(chan2dev(&atchan->chan), "read bus error!!!"); if (atchan->status & AT_XDMAC_CIS_WBEIS) dev_err(chan2dev(&atchan->chan), "write bus error!!!"); if (atchan->status & AT_XDMAC_CIS_ROIS) dev_err(chan2dev(&atchan->chan), "request overflow error!!!"); spin_lock_bh(&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); BUG_ON(!desc->active_xfer); txd = &desc->tx_dma_desc; at_xdmac_remove_xfer(atchan, desc); spin_unlock_bh(&atchan->lock); if (!at_xdmac_chan_is_cyclic(atchan)) { dma_cookie_complete(txd); if (txd->callback && (txd->flags & DMA_PREP_INTERRUPT)) txd->callback(txd->callback_param); } dma_run_dependencies(txd); at_xdmac_advance_work(atchan); } } 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->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->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); dev_dbg(chan2dev(&atchan->chan), "%s\n", __func__); if (!at_xdmac_chan_is_cyclic(atchan)) at_xdmac_advance_work(atchan); return; } static int at_xdmac_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned long arg) { 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); int ret = 0; dev_dbg(chan2dev(chan), "%s: cmd=%d\n", __func__, cmd); spin_lock_bh(&atchan->lock); switch (cmd) { case DMA_PAUSE: at_xdmac_write(atxdmac, AT_XDMAC_GRWS, atchan->mask); set_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status); break; case DMA_RESUME: if (!at_xdmac_chan_is_paused(atchan)) break; at_xdmac_write(atxdmac, AT_XDMAC_GRWR, atchan->mask); clear_bit(AT_XDMAC_CHAN_IS_PAUSED, &atchan->status); break; case DMA_TERMINATE_ALL: 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) at_xdmac_remove_xfer(atchan, desc); clear_bit(AT_XDMAC_CHAN_IS_CYCLIC, &atchan->status); break; case DMA_SLAVE_CONFIG: ret = at_xdmac_set_slave_config(chan, (struct dma_slave_config *)arg); break; default: dev_err(chan2dev(chan), "unmanaged or unknown dma control cmd: %d\n", cmd); ret = -ENXIO; } spin_unlock_bh(&atchan->lock); return ret; } 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; spin_lock_bh(&atchan->lock); if (at_xdmac_chan_is_enabled(atchan)) { dev_err(chan2dev(chan), "can't allocate channel resources (channel enabled)\n"); i = -EIO; goto spin_unlock; } if (!list_empty(&atchan->free_descs_list)) { dev_err(chan2dev(chan), "can't allocate channel resources (channel not free from a previous use)\n"); i = -EIO; goto spin_unlock; } for (i = 0; i < init_nr_desc_per_channel; i++) { desc = at_xdmac_alloc_desc(chan, GFP_ATOMIC); if (!desc) { 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); spin_unlock: spin_unlock_bh(&atchan->lock); 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; } #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)) static int at_xdmac_device_slave_caps(struct dma_chan *dchan, struct dma_slave_caps *caps) { caps->src_addr_widths = AT_XDMAC_DMA_BUSWIDTHS; caps->dstn_addr_widths = AT_XDMAC_DMA_BUSWIDTHS; caps->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); caps->cmd_pause = true; caps->cmd_terminate = true; caps->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; return 0; } #ifdef CONFIG_PM static int atmel_xdmac_prepare(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct at_xdmac *atxdmac = platform_get_drvdata(pdev); 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 platform_device *pdev = to_platform_device(dev); struct at_xdmac *atxdmac = platform_get_drvdata(pdev); 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); if (at_xdmac_chan_is_cyclic(atchan)) { if (!at_xdmac_chan_is_paused(atchan)) at_xdmac_control(chan, DMA_PAUSE, 0); 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); at_xdmac_off(atxdmac); clk_disable_unprepare(atxdmac->clk); return 0; } static int atmel_xdmac_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct at_xdmac *atxdmac = platform_get_drvdata(pdev); struct at_xdmac_chan *atchan; struct dma_chan *chan, *_chan; int i; u32 cfg; clk_prepare_enable(atxdmac->clk); /* 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); at_xdmac_write(atxdmac, AT_XDMAC_GE, atxdmac->save_gs); list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) { atchan = to_at_xdmac_chan(chan); cfg = atchan->cfg[AT_XDMAC_CUR_CFG]; at_xdmac_chan_write(atchan, AT_XDMAC_CC, cfg); if (at_xdmac_chan_is_cyclic(atchan)) { 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(); 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 resource *res; struct at_xdmac *atxdmac; int irq, size, nr_channels, i, ret; void __iomem *base; u32 reg; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) return -EINVAL; irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; base = devm_ioremap_resource(&pdev->dev, res); 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_MEMCPY, atxdmac->dma.cap_mask); dma_cap_set(DMA_SLAVE, 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_dma_memcpy = at_xdmac_prep_dma_memcpy; atxdmac->dma.device_prep_slave_sg = at_xdmac_prep_slave_sg; atxdmac->dma.device_control = at_xdmac_control; atxdmac->dma.chancnt = nr_channels; atxdmac->dma.device_slave_caps = at_xdmac_device_slave_caps; /* 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_init(&atchan->tasklet, at_xdmac_tasklet, (unsigned long)atchan); /* 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->dma.dev); 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); synchronize_irq(atxdmac->irq); free_irq(atxdmac->irq, atxdmac->dma.dev); 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", .owner = THIS_MODULE, .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 "); MODULE_LICENSE("GPL");