diff options
Diffstat (limited to 'drivers/dma/at_xdmac.c')
| -rw-r--r-- | drivers/dma/at_xdmac.c | 1582 |
1 files changed, 1582 insertions, 0 deletions
diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c new file mode 100644 index 000000000..7992164ea --- /dev/null +++ b/drivers/dma/at_xdmac.c @@ -0,0 +1,1582 @@ +/* + * Driver for the Atmel Extensible DMA Controller (aka XDMAC on AT91 systems) + * + * Copyright (C) 2014 Atmel Corporation + * + * Author: Ludovic Desroches <ludovic.desroches@atmel.com> + * + * 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 <http://www.gnu.org/licenses/>. + */ + +#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_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 +#define AT_XDMAC_MAX_CSIZE 16 /* 16 data */ +#define AT_XDMAC_MAX_DWIDTH 8 /* 64 bits */ + +#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; + 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[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 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; + at_xdmac_chan_write(atchan, AT_XDMAC_CC, first->lld.mbr_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; + unsigned long irqflags; + + spin_lock_irqsave(&atchan->lock, irqflags); + 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_irqrestore(&atchan->lock, irqflags); + 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_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_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; + } + desc->lld.mbr_cfg = atchan->cfg; + dwidth = at_xdmac_get_dwidth(desc->lld.mbr_cfg); + fixed_dwidth = IS_ALIGNED(len, 1 << dwidth) + ? at_xdmac_get_dwidth(desc->lld.mbr_cfg) + : 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 */ + | (i == sg_len - 1 ? 0 : AT_XDMAC_MBR_UBC_NDE) /* descriptor fetch */ + | (len >> fixed_dwidth); /* microblock length */ + 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) { + prev->lld.mbr_nda = desc->tx_dma_desc.phys; + dev_dbg(chan2dev(chan), + "%s: chain lld: prev=0x%p, mbr_nda=%pad\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); + 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_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 + | AT_XDMAC_MBR_UBC_NDE + | 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) { + prev->lld.mbr_nda = desc->tx_dma_desc.phys; + dev_dbg(chan2dev(chan), + "%s: chain lld: prev=0x%p, mbr_nda=%pad\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=%pad\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; + 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; + + /* + * 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=%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_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. */ + 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=%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) { + 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, mask, value; + u8 dwidth = 0; + unsigned long flags; + + 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. + */ + 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(); + } + + 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) { + dwidth = at_xdmac_get_dwidth(desc->lld.mbr_cfg); + 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; + + 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; +} + +/* 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; + unsigned long flags; + + spin_lock_irqsave(&atchan->lock, flags); + + /* + * 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_irqrestore(&atchan->lock, flags); +} + +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_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) + at_xdmac_remove_xfer(atchan, desc); + + 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; + unsigned long flags; + + spin_lock_irqsave(&atchan->lock, flags); + + 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_irqrestore(&atchan->lock, flags); + 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 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); + + 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); + + 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; + + 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); + at_xdmac_chan_write(atchan, AT_XDMAC_CC, atchan->save_cc); + 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); + /* + * 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_dma_memcpy = at_xdmac_prep_dma_memcpy; + 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_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", + .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"); |