From a2f673d1aa39752608e5f4838ed9656b38cbc4b9 Mon Sep 17 00:00:00 2001 From: Phil Elwell Date: Thu, 4 Apr 2019 13:33:47 +0100 Subject: [PATCH] bcm2835-dma: Add proper 40-bit DMA support BCM2711 has 4 DMA channels with a 40-bit address range, allowing them to access the full 4GB of memory on a Pi 4. Signed-off-by: Phil Elwell --- drivers/dma/bcm2835-dma.c | 485 ++++++++++++++++++++++++++++++++------ 1 file changed, 412 insertions(+), 73 deletions(-) --- a/drivers/dma/bcm2835-dma.c +++ b/drivers/dma/bcm2835-dma.c @@ -38,6 +38,11 @@ #define BCM2835_DMA_MAX_DMA_CHAN_SUPPORTED 14 #define BCM2835_DMA_CHAN_NAME_SIZE 8 #define BCM2835_DMA_BULK_MASK BIT(0) +#define BCM2711_DMA_MEMCPY_CHAN 14 + +struct bcm2835_dma_cfg_data { + u32 chan_40bit_mask; +}; /** * struct bcm2835_dmadev - BCM2835 DMA controller @@ -52,6 +57,7 @@ struct bcm2835_dmadev { void __iomem *base; struct device_dma_parameters dma_parms; dma_addr_t zero_page; + const struct bcm2835_dma_cfg_data *cfg_data; }; struct bcm2835_dma_cb { @@ -64,6 +70,17 @@ struct bcm2835_dma_cb { uint32_t pad[2]; }; +struct bcm2711_dma40_scb { + uint32_t ti; + uint32_t src; + uint32_t srci; + uint32_t dst; + uint32_t dsti; + uint32_t len; + uint32_t next_cb; + uint32_t rsvd; +}; + struct bcm2835_cb_entry { struct bcm2835_dma_cb *cb; dma_addr_t paddr; @@ -84,6 +101,7 @@ struct bcm2835_chan { unsigned int irq_flags; bool is_lite_channel; + bool is_40bit_channel; }; struct bcm2835_desc { @@ -173,13 +191,118 @@ struct bcm2835_desc { #define BCM2835_DMA_DATA_TYPE_S128 16 /* Valid only for channels 0 - 14, 15 has its own base address */ -#define BCM2835_DMA_CHAN(n) ((n) << 8) /* Base address */ +#define BCM2835_DMA_CHAN_SIZE 0x100 +#define BCM2835_DMA_CHAN(n) ((n) * BCM2835_DMA_CHAN_SIZE) /* Base address */ #define BCM2835_DMA_CHANIO(base, n) ((base) + BCM2835_DMA_CHAN(n)) /* the max dma length for different channels */ #define MAX_DMA_LEN SZ_1G #define MAX_LITE_DMA_LEN (SZ_64K - 4) +/* 40-bit DMA support */ +#define BCM2711_DMA40_CS 0x00 +#define BCM2711_DMA40_CB 0x04 +#define BCM2711_DMA40_DEBUG 0x0c +#define BCM2711_DMA40_TI 0x10 +#define BCM2711_DMA40_SRC 0x14 +#define BCM2711_DMA40_SRCI 0x18 +#define BCM2711_DMA40_DEST 0x1c +#define BCM2711_DMA40_DESTI 0x20 +#define BCM2711_DMA40_LEN 0x24 +#define BCM2711_DMA40_NEXT_CB 0x28 +#define BCM2711_DMA40_DEBUG2 0x2c + +#define BCM2711_DMA40_ACTIVE BIT(0) +#define BCM2711_DMA40_END BIT(1) +#define BCM2711_DMA40_INT BIT(2) +#define BCM2711_DMA40_DREQ BIT(3) /* DREQ state */ +#define BCM2711_DMA40_RD_PAUSED BIT(4) /* Reading is paused */ +#define BCM2711_DMA40_WR_PAUSED BIT(5) /* Writing is paused */ +#define BCM2711_DMA40_DREQ_PAUSED BIT(6) /* Is paused by DREQ flow control */ +#define BCM2711_DMA40_WAITING_FOR_WRITES BIT(7) /* Waiting for last write */ +#define BCM2711_DMA40_ERR BIT(10) +#define BCM2711_DMA40_QOS(x) (((x) & 0x1f) << 16) +#define BCM2711_DMA40_PANIC_QOS(x) (((x) & 0x1f) << 20) +#define BCM2711_DMA40_WAIT_FOR_WRITES BIT(28) +#define BCM2711_DMA40_DISDEBUG BIT(29) +#define BCM2711_DMA40_ABORT BIT(30) +#define BCM2711_DMA40_HALT BIT(31) +#define BCM2711_DMA40_CS_FLAGS(x) (x & (BCM2711_DMA40_QOS(15) | \ + BCM2711_DMA40_PANIC_QOS(15) | \ + BCM2711_DMA40_WAIT_FOR_WRITES | \ + BCM2711_DMA40_DISDEBUG)) + +/* Transfer information bits */ +#define BCM2711_DMA40_INTEN BIT(0) +#define BCM2711_DMA40_TDMODE BIT(1) /* 2D-Mode */ +#define BCM2711_DMA40_WAIT_RESP BIT(2) /* wait for AXI write to be acked */ +#define BCM2711_DMA40_WAIT_RD_RESP BIT(3) /* wait for AXI read to complete */ +#define BCM2711_DMA40_PER_MAP(x) ((x & 31) << 9) /* REQ source */ +#define BCM2711_DMA40_S_DREQ BIT(14) /* enable SREQ for source */ +#define BCM2711_DMA40_D_DREQ BIT(15) /* enable DREQ for destination */ +#define BCM2711_DMA40_S_WAIT(x) ((x & 0xff) << 16) /* add DMA read-wait cycles */ +#define BCM2711_DMA40_D_WAIT(x) ((x & 0xff) << 24) /* add DMA write-wait cycles */ + +/* debug register bits */ +#define BCM2711_DMA40_DEBUG_WRITE_ERR BIT(0) +#define BCM2711_DMA40_DEBUG_FIFO_ERR BIT(1) +#define BCM2711_DMA40_DEBUG_READ_ERR BIT(2) +#define BCM2711_DMA40_DEBUG_READ_CB_ERR BIT(3) +#define BCM2711_DMA40_DEBUG_IN_ON_ERR BIT(8) +#define BCM2711_DMA40_DEBUG_ABORT_ON_ERR BIT(9) +#define BCM2711_DMA40_DEBUG_HALT_ON_ERR BIT(10) +#define BCM2711_DMA40_DEBUG_DISABLE_CLK_GATE BIT(11) +#define BCM2711_DMA40_DEBUG_RSTATE_SHIFT 14 +#define BCM2711_DMA40_DEBUG_RSTATE_BITS 4 +#define BCM2711_DMA40_DEBUG_WSTATE_SHIFT 18 +#define BCM2711_DMA40_DEBUG_WSTATE_BITS 4 +#define BCM2711_DMA40_DEBUG_RESET BIT(23) +#define BCM2711_DMA40_DEBUG_ID_SHIFT 24 +#define BCM2711_DMA40_DEBUG_ID_BITS 4 +#define BCM2711_DMA40_DEBUG_VERSION_SHIFT 28 +#define BCM2711_DMA40_DEBUG_VERSION_BITS 4 + +/* Valid only for channels 0 - 3 (11 - 14) */ +#define BCM2711_DMA40_CHAN(n) (((n) + 11) << 8) /* Base address */ +#define BCM2711_DMA40_CHANIO(base, n) ((base) + BCM2711_DMA_CHAN(n)) + +/* the max dma length for different channels */ +#define MAX_DMA40_LEN SZ_1G + +#define BCM2711_DMA40_BURST_LEN(x) ((min(x,16) - 1) << 8) +#define BCM2711_DMA40_INC BIT(12) +#define BCM2711_DMA40_SIZE_32 (0 << 13) +#define BCM2711_DMA40_SIZE_64 (1 << 13) +#define BCM2711_DMA40_SIZE_128 (2 << 13) +#define BCM2711_DMA40_SIZE_256 (3 << 13) +#define BCM2711_DMA40_IGNORE BIT(15) +#define BCM2711_DMA40_STRIDE(x) ((x) << 16) /* For 2D mode */ + +#define BCM2711_DMA40_MEMCPY_FLAGS \ + (BCM2711_DMA40_QOS(0) | \ + BCM2711_DMA40_PANIC_QOS(0) | \ + BCM2711_DMA40_WAIT_FOR_WRITES | \ + BCM2711_DMA40_DISDEBUG) + +#define BCM2711_DMA40_MEMCPY_XFER_INFO \ + (BCM2711_DMA40_SIZE_128 | \ + BCM2711_DMA40_INC | \ + BCM2711_DMA40_BURST_LEN(16)) + +struct bcm2835_dmadev *memcpy_parent; +static void __iomem *memcpy_chan; +static struct bcm2711_dma40_scb *memcpy_scb; +static dma_addr_t memcpy_scb_dma; +DEFINE_SPINLOCK(memcpy_lock); + +static const struct bcm2835_dma_cfg_data bcm2835_dma_cfg = { + .chan_40bit_mask = 0, +}; + +static const struct bcm2835_dma_cfg_data bcm2711_dma_cfg = { + .chan_40bit_mask = BIT(11) | BIT(12) | BIT(13) | BIT(14), +}; + static inline size_t bcm2835_dma_max_frame_length(struct bcm2835_chan *c) { /* lite and normal channels have different max frame length */ @@ -209,6 +332,32 @@ static inline struct bcm2835_desc *to_bc return container_of(t, struct bcm2835_desc, vd.tx); } +static inline uint32_t to_bcm2711_ti(uint32_t info) +{ + return ((info & BCM2835_DMA_INT_EN) ? BCM2711_DMA40_INTEN : 0) | + ((info & BCM2835_DMA_WAIT_RESP) ? BCM2711_DMA40_WAIT_RESP : 0) | + ((info & BCM2835_DMA_S_DREQ) ? + (BCM2711_DMA40_S_DREQ | BCM2711_DMA40_WAIT_RD_RESP) : 0) | + ((info & BCM2835_DMA_D_DREQ) ? BCM2711_DMA40_D_DREQ : 0) | + BCM2711_DMA40_PER_MAP((info >> 16) & 0x1f); +} + +static inline uint32_t to_bcm2711_srci(uint32_t info) +{ + return ((info & BCM2835_DMA_S_INC) ? BCM2711_DMA40_INC : 0); +} + +static inline uint32_t to_bcm2711_dsti(uint32_t info) +{ + return ((info & BCM2835_DMA_D_INC) ? BCM2711_DMA40_INC : 0); +} + +static inline uint32_t to_bcm2711_cbaddr(dma_addr_t addr) +{ + BUG_ON(addr & 0x1f); + return (addr >> 5); +} + static void bcm2835_dma_free_cb_chain(struct bcm2835_desc *desc) { size_t i; @@ -227,45 +376,53 @@ static void bcm2835_dma_desc_free(struct } static void bcm2835_dma_create_cb_set_length( - struct bcm2835_chan *chan, + struct bcm2835_chan *c, struct bcm2835_dma_cb *control_block, size_t len, size_t period_len, size_t *total_len, u32 finalextrainfo) { - size_t max_len = bcm2835_dma_max_frame_length(chan); + size_t max_len = bcm2835_dma_max_frame_length(c); + uint32_t cb_len; /* set the length taking lite-channel limitations into account */ - control_block->length = min_t(u32, len, max_len); + cb_len = min_t(u32, len, max_len); - /* finished if we have no period_length */ - if (!period_len) - return; + if (period_len) { + /* + * period_len means: that we need to generate + * transfers that are terminating at every + * multiple of period_len - this is typically + * used to set the interrupt flag in info + * which is required during cyclic transfers + */ - /* - * period_len means: that we need to generate - * transfers that are terminating at every - * multiple of period_len - this is typically - * used to set the interrupt flag in info - * which is required during cyclic transfers - */ + /* have we filled in period_length yet? */ + if (*total_len + cb_len < period_len) { + /* update number of bytes in this period so far */ + *total_len += cb_len; + } else { + /* calculate the length that remains to reach period_len */ + cb_len = period_len - *total_len; - /* have we filled in period_length yet? */ - if (*total_len + control_block->length < period_len) { - /* update number of bytes in this period so far */ - *total_len += control_block->length; - return; + /* reset total_length for next period */ + *total_len = 0; + } } - /* calculate the length that remains to reach period_length */ - control_block->length = period_len - *total_len; - - /* reset total_length for next period */ - *total_len = 0; - - /* add extrainfo bits in info */ - control_block->info |= finalextrainfo; + if (c->is_40bit_channel) { + struct bcm2711_dma40_scb *scb = + (struct bcm2711_dma40_scb *)control_block; + + scb->len = cb_len; + /* add extrainfo bits to ti */ + scb->ti |= to_bcm2711_ti(finalextrainfo); + } else { + control_block->length = cb_len; + /* add extrainfo bits to info */ + control_block->info |= finalextrainfo; + } } static inline size_t bcm2835_dma_count_frames_for_sg( @@ -288,7 +445,7 @@ static inline size_t bcm2835_dma_count_f /** * bcm2835_dma_create_cb_chain - create a control block and fills data in * - * @chan: the @dma_chan for which we run this + * @c: the @bcm2835_chan for which we run this * @direction: the direction in which we transfer * @cyclic: it is a cyclic transfer * @info: the default info bits to apply per controlblock @@ -306,12 +463,11 @@ static inline size_t bcm2835_dma_count_f * @gfp: the GFP flag to use for allocation */ static struct bcm2835_desc *bcm2835_dma_create_cb_chain( - struct dma_chan *chan, enum dma_transfer_direction direction, + struct bcm2835_chan *c, enum dma_transfer_direction direction, bool cyclic, u32 info, u32 finalextrainfo, size_t frames, dma_addr_t src, dma_addr_t dst, size_t buf_len, size_t period_len, gfp_t gfp) { - struct bcm2835_chan *c = to_bcm2835_dma_chan(chan); size_t len = buf_len, total_len; size_t frame; struct bcm2835_desc *d; @@ -343,11 +499,23 @@ static struct bcm2835_desc *bcm2835_dma_ /* fill in the control block */ control_block = cb_entry->cb; - control_block->info = info; - control_block->src = src; - control_block->dst = dst; - control_block->stride = 0; - control_block->next = 0; + if (c->is_40bit_channel) { + struct bcm2711_dma40_scb *scb = + (struct bcm2711_dma40_scb *)control_block; + scb->ti = to_bcm2711_ti(info); + scb->src = lower_32_bits(src); + scb->srci= upper_32_bits(src) | to_bcm2711_srci(info); + scb->dst = lower_32_bits(dst); + scb->dsti = upper_32_bits(dst) | to_bcm2711_dsti(info); + scb->next_cb = 0; + } else { + control_block->info = info; + control_block->src = src; + control_block->dst = dst; + control_block->stride = 0; + control_block->next = 0; + } + /* set up length in control_block if requested */ if (buf_len) { /* calculate length honoring period_length */ @@ -361,7 +529,11 @@ static struct bcm2835_desc *bcm2835_dma_ } /* link this the last controlblock */ - if (frame) + if (frame && c->is_40bit_channel) + ((struct bcm2711_dma40_scb *) + d->cb_list[frame - 1].cb)->next_cb = + to_bcm2711_cbaddr(cb_entry->paddr); + if (frame && !c->is_40bit_channel) d->cb_list[frame - 1].cb->next = cb_entry->paddr; /* update src and dst and length */ @@ -371,11 +543,21 @@ static struct bcm2835_desc *bcm2835_dma_ dst += control_block->length; /* Length of total transfer */ - d->size += control_block->length; + if (c->is_40bit_channel) + d->size += ((struct bcm2711_dma40_scb *)control_block)->len; + else + d->size += control_block->length; } /* the last frame requires extra flags */ - d->cb_list[d->frames - 1].cb->info |= finalextrainfo; + if (c->is_40bit_channel) { + struct bcm2711_dma40_scb *scb = + (struct bcm2711_dma40_scb *)d->cb_list[d->frames-1].cb; + + scb->ti |= to_bcm2711_ti(finalextrainfo); + } else { + d->cb_list[d->frames - 1].cb->info |= finalextrainfo; + } /* detect a size missmatch */ if (buf_len && (d->size != buf_len)) @@ -389,13 +571,12 @@ error_cb: } static void bcm2835_dma_fill_cb_chain_with_sg( - struct dma_chan *chan, + struct bcm2835_chan *c, enum dma_transfer_direction direction, struct bcm2835_cb_entry *cb, struct scatterlist *sgl, unsigned int sg_len) { - struct bcm2835_chan *c = to_bcm2835_dma_chan(chan); size_t len, max_len; unsigned int i; dma_addr_t addr; @@ -403,14 +584,35 @@ static void bcm2835_dma_fill_cb_chain_wi max_len = bcm2835_dma_max_frame_length(c); for_each_sg(sgl, sgent, sg_len, i) { - for (addr = sg_dma_address(sgent), len = sg_dma_len(sgent); - len > 0; - addr += cb->cb->length, len -= cb->cb->length, cb++) { - if (direction == DMA_DEV_TO_MEM) - cb->cb->dst = addr; - else - cb->cb->src = addr; - cb->cb->length = min(len, max_len); + if (c->is_40bit_channel) { + struct bcm2711_dma40_scb *scb; + + for (addr = sg_dma_address(sgent), + len = sg_dma_len(sgent); + len > 0; + addr += scb->len, len -= scb->len, cb++) { + scb = (struct bcm2711_dma40_scb *)cb->cb; + if (direction == DMA_DEV_TO_MEM) { + scb->dst = lower_32_bits(addr); + scb->dsti = upper_32_bits(addr) | BCM2711_DMA40_INC; + } else { + scb->src = lower_32_bits(addr); + scb->srci = upper_32_bits(addr) | BCM2711_DMA40_INC; + } + scb->len = min(len, max_len); + } + } else { + for (addr = sg_dma_address(sgent), + len = sg_dma_len(sgent); + len > 0; + addr += cb->cb->length, len -= cb->cb->length, + cb++) { + if (direction == DMA_DEV_TO_MEM) + cb->cb->dst = addr; + else + cb->cb->src = addr; + cb->cb->length = min(len, max_len); + } } } } @@ -419,6 +621,10 @@ static void bcm2835_dma_abort(struct bcm { void __iomem *chan_base = c->chan_base; long int timeout = 10000; + u32 wait_mask = BCM2835_DMA_WAITING_FOR_WRITES; + + if (c->is_40bit_channel) + wait_mask = BCM2711_DMA40_WAITING_FOR_WRITES; /* * A zero control block address means the channel is idle. @@ -431,8 +637,7 @@ static void bcm2835_dma_abort(struct bcm writel(0, chan_base + BCM2835_DMA_CS); /* Wait for any current AXI transfer to complete */ - while ((readl(chan_base + BCM2835_DMA_CS) & - BCM2835_DMA_WAITING_FOR_WRITES) && --timeout) + while ((readl(chan_base + BCM2835_DMA_CS) & wait_mask) && --timeout) cpu_relax(); /* Peripheral might be stuck and fail to signal AXI write responses */ @@ -457,9 +662,16 @@ static void bcm2835_dma_start_desc(struc c->desc = d = to_bcm2835_dma_desc(&vd->tx); - writel(d->cb_list[0].paddr, c->chan_base + BCM2835_DMA_ADDR); - writel(BCM2835_DMA_ACTIVE | BCM2835_DMA_CS_FLAGS(c->dreq), - c->chan_base + BCM2835_DMA_CS); + if (c->is_40bit_channel) { + writel(to_bcm2711_cbaddr(d->cb_list[0].paddr), + c->chan_base + BCM2711_DMA40_CB); + writel(BCM2711_DMA40_ACTIVE | BCM2711_DMA40_CS_FLAGS(c->dreq), + c->chan_base + BCM2711_DMA40_CS); + } else { + writel(d->cb_list[0].paddr, c->chan_base + BCM2835_DMA_ADDR); + writel(BCM2835_DMA_ACTIVE | BCM2835_DMA_CS_FLAGS(c->dreq), + c->chan_base + BCM2835_DMA_CS); + } } static irqreturn_t bcm2835_dma_callback(int irq, void *data) @@ -486,8 +698,7 @@ static irqreturn_t bcm2835_dma_callback( * if this IRQ handler is threaded.) If the channel is finished, it * will remain idle despite the ACTIVE flag being set. */ - writel(BCM2835_DMA_INT | BCM2835_DMA_ACTIVE | - BCM2835_DMA_CS_FLAGS(c->dreq), + writel(BCM2835_DMA_INT | BCM2835_DMA_ACTIVE, c->chan_base + BCM2835_DMA_CS); d = c->desc; @@ -590,9 +801,17 @@ static enum dma_status bcm2835_dma_tx_st struct bcm2835_desc *d = c->desc; dma_addr_t pos; - if (d->dir == DMA_MEM_TO_DEV) + if (d->dir == DMA_MEM_TO_DEV && c->is_40bit_channel) + pos = readl(c->chan_base + BCM2711_DMA40_SRC) + + ((readl(c->chan_base + BCM2711_DMA40_SRCI) & + 0xff) << 8); + else if (d->dir == DMA_MEM_TO_DEV && !c->is_40bit_channel) pos = readl(c->chan_base + BCM2835_DMA_SOURCE_AD); - else if (d->dir == DMA_DEV_TO_MEM) + else if (d->dir == DMA_DEV_TO_MEM && c->is_40bit_channel) + pos = readl(c->chan_base + BCM2711_DMA40_DEST) + + ((readl(c->chan_base + BCM2711_DMA40_DESTI) & + 0xff) << 8); + else if (d->dir == DMA_DEV_TO_MEM && !c->is_40bit_channel) pos = readl(c->chan_base + BCM2835_DMA_DEST_AD); else pos = 0; @@ -638,7 +857,7 @@ static struct dma_async_tx_descriptor *b frames = bcm2835_dma_frames_for_length(len, max_len); /* allocate the CB chain - this also fills in the pointers */ - d = bcm2835_dma_create_cb_chain(chan, DMA_MEM_TO_MEM, false, + d = bcm2835_dma_create_cb_chain(c, DMA_MEM_TO_MEM, false, info, extra, frames, src, dst, len, 0, GFP_KERNEL); if (!d) @@ -673,11 +892,21 @@ static struct dma_async_tx_descriptor *b if (c->cfg.src_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) return NULL; src = c->cfg.src_addr; + /* + * One would think it ought to be possible to get the physical + * to dma address mapping information from the dma-ranges DT + * property, but I've not found a way yet that doesn't involve + * open-coding the whole thing. + */ + if (c->is_40bit_channel) + src |= 0x400000000ull; info |= BCM2835_DMA_S_DREQ | BCM2835_DMA_D_INC; } else { if (c->cfg.dst_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) return NULL; dst = c->cfg.dst_addr; + if (c->is_40bit_channel) + dst |= 0x400000000ull; info |= BCM2835_DMA_D_DREQ | BCM2835_DMA_S_INC; } @@ -685,7 +914,7 @@ static struct dma_async_tx_descriptor *b frames = bcm2835_dma_count_frames_for_sg(c, sgl, sg_len); /* allocate the CB chain */ - d = bcm2835_dma_create_cb_chain(chan, direction, false, + d = bcm2835_dma_create_cb_chain(c, direction, false, info, extra, frames, src, dst, 0, 0, GFP_NOWAIT); @@ -693,7 +922,7 @@ static struct dma_async_tx_descriptor *b return NULL; /* fill in frames with scatterlist pointers */ - bcm2835_dma_fill_cb_chain_with_sg(chan, direction, d->cb_list, + bcm2835_dma_fill_cb_chain_with_sg(c, direction, d->cb_list, sgl, sg_len); return vchan_tx_prep(&c->vc, &d->vd, flags); @@ -747,12 +976,16 @@ static struct dma_async_tx_descriptor *b if (c->cfg.src_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) return NULL; src = c->cfg.src_addr; + if (c->is_40bit_channel) + src |= 0x400000000ull; dst = buf_addr; info |= BCM2835_DMA_S_DREQ | BCM2835_DMA_D_INC; } else { if (c->cfg.dst_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES) return NULL; dst = c->cfg.dst_addr; + if (c->is_40bit_channel) + dst |= 0x400000000ull; src = buf_addr; info |= BCM2835_DMA_D_DREQ | BCM2835_DMA_S_INC; @@ -772,7 +1005,7 @@ static struct dma_async_tx_descriptor *b * note that we need to use GFP_NOWAIT, as the ALSA i2s dmaengine * implementation calls prep_dma_cyclic with interrupts disabled. */ - d = bcm2835_dma_create_cb_chain(chan, direction, true, + d = bcm2835_dma_create_cb_chain(c, direction, true, info, extra, frames, src, dst, buf_len, period_len, GFP_NOWAIT); @@ -780,7 +1013,12 @@ static struct dma_async_tx_descriptor *b return NULL; /* wrap around into a loop */ - d->cb_list[d->frames - 1].cb->next = d->cb_list[0].paddr; + if (c->is_40bit_channel) + ((struct bcm2711_dma40_scb *) + d->cb_list[frames - 1].cb)->next_cb = + to_bcm2711_cbaddr(d->cb_list[0].paddr); + else + d->cb_list[d->frames - 1].cb->next = d->cb_list[0].paddr; return vchan_tx_prep(&c->vc, &d->vd, flags); } @@ -844,9 +1082,11 @@ static int bcm2835_dma_chan_init(struct c->irq_number = irq; c->irq_flags = irq_flags; - /* check in DEBUG register if this is a LITE channel */ - if (readl(c->chan_base + BCM2835_DMA_DEBUG) & - BCM2835_DMA_DEBUG_LITE) + /* check for 40bit and lite channels */ + if (d->cfg_data->chan_40bit_mask & BIT(chan_id)) + c->is_40bit_channel = true; + else if (readl(c->chan_base + BCM2835_DMA_DEBUG) & + BCM2835_DMA_DEBUG_LITE) c->is_lite_channel = true; return 0; @@ -866,8 +1106,58 @@ static void bcm2835_dma_free(struct bcm2 DMA_TO_DEVICE, DMA_ATTR_SKIP_CPU_SYNC); } +int bcm2711_dma40_memcpy_init(void) +{ + if (!memcpy_parent) + return -EPROBE_DEFER; + + if (!memcpy_chan) + return -EINVAL; + + if (!memcpy_scb) + return -ENOMEM; + + return 0; +} +EXPORT_SYMBOL(bcm2711_dma40_memcpy_init); + +void bcm2711_dma40_memcpy(dma_addr_t dst, dma_addr_t src, size_t size) +{ + struct bcm2711_dma40_scb *scb = memcpy_scb; + unsigned long flags; + + if (!scb) { + pr_err("bcm2711_dma40_memcpy not initialised!\n"); + return; + } + + spin_lock_irqsave(&memcpy_lock, flags); + + scb->ti = 0; + scb->src = lower_32_bits(src); + scb->srci = upper_32_bits(src) | BCM2711_DMA40_MEMCPY_XFER_INFO; + scb->dst = lower_32_bits(dst); + scb->dsti = upper_32_bits(dst) | BCM2711_DMA40_MEMCPY_XFER_INFO; + scb->len = size; + scb->next_cb = 0; + + writel((u32)(memcpy_scb_dma >> 5), memcpy_chan + BCM2711_DMA40_CB); + writel(BCM2711_DMA40_MEMCPY_FLAGS + BCM2711_DMA40_ACTIVE, + memcpy_chan + BCM2711_DMA40_CS); + + /* Poll for completion */ + while (!(readl(memcpy_chan + BCM2711_DMA40_CS) & BCM2711_DMA40_END)) + cpu_relax(); + + writel(BCM2711_DMA40_END, memcpy_chan + BCM2711_DMA40_CS); + + spin_unlock_irqrestore(&memcpy_lock, flags); +} +EXPORT_SYMBOL(bcm2711_dma40_memcpy); + static const struct of_device_id bcm2835_dma_of_match[] = { - { .compatible = "brcm,bcm2835-dma", }, + { .compatible = "brcm,bcm2835-dma", .data = &bcm2835_dma_cfg }, + { .compatible = "brcm,bcm2711-dma", .data = &bcm2711_dma_cfg }, {}, }; MODULE_DEVICE_TABLE(of, bcm2835_dma_of_match); @@ -899,6 +1189,8 @@ static int bcm2835_dma_probe(struct plat int irq_flags; uint32_t chans_available; char chan_name[BCM2835_DMA_CHAN_NAME_SIZE]; + const struct of_device_id *of_id; + int chan_count, chan_start, chan_end; if (!pdev->dev.dma_mask) pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask; @@ -920,9 +1212,13 @@ static int bcm2835_dma_probe(struct plat base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(base)) return PTR_ERR(base); - rc = bcm_dmaman_probe(pdev, base, BCM2835_DMA_BULK_MASK); - if (rc) - dev_err(&pdev->dev, "Failed to initialize the legacy API\n"); + + /* The set of channels can be split across multiple instances. */ + chan_start = ((u32)(uintptr_t)base / BCM2835_DMA_CHAN_SIZE) & 0xf; + base -= BCM2835_DMA_CHAN(chan_start); + chan_count = resource_size(res) / BCM2835_DMA_CHAN_SIZE; + chan_end = min(chan_start + chan_count, + BCM2835_DMA_MAX_DMA_CHAN_SUPPORTED + 1); od->base = base; @@ -959,6 +1255,14 @@ static int bcm2835_dma_probe(struct plat return -ENOMEM; } + of_id = of_match_node(bcm2835_dma_of_match, pdev->dev.of_node); + if (!of_id) { + dev_err(&pdev->dev, "Failed to match compatible string\n"); + return -EINVAL; + } + + od->cfg_data = of_id->data; + /* Request DMA channel mask from device tree */ if (of_property_read_u32(pdev->dev.of_node, "brcm,dma-channel-mask", @@ -968,11 +1272,34 @@ static int bcm2835_dma_probe(struct plat goto err_no_dma; } - /* Channel 0 is used by the legacy API */ - chans_available &= ~BCM2835_DMA_BULK_MASK; + /* One channel is reserved for the legacy API */ + if (chans_available & BCM2835_DMA_BULK_MASK) { + rc = bcm_dmaman_probe(pdev, base, + chans_available & BCM2835_DMA_BULK_MASK); + if (rc) + dev_err(&pdev->dev, + "Failed to initialize the legacy API\n"); + + chans_available &= ~BCM2835_DMA_BULK_MASK; + } + + /* And possibly one for the 40-bit DMA memcpy API */ + if (chans_available & od->cfg_data->chan_40bit_mask & + BIT(BCM2711_DMA_MEMCPY_CHAN)) { + memcpy_parent = od; + memcpy_chan = BCM2835_DMA_CHANIO(base, BCM2711_DMA_MEMCPY_CHAN); + memcpy_scb = dma_alloc_coherent(memcpy_parent->ddev.dev, + sizeof(*memcpy_scb), + &memcpy_scb_dma, GFP_KERNEL); + if (!memcpy_scb) + dev_warn(&pdev->dev, + "Failed to allocated memcpy scb\n"); + + chans_available &= ~BIT(BCM2711_DMA_MEMCPY_CHAN); + } /* get irqs for each channel that we support */ - for (i = 0; i <= BCM2835_DMA_MAX_DMA_CHAN_SUPPORTED; i++) { + for (i = chan_start; i < chan_end; i++) { /* skip masked out channels */ if (!(chans_available & (1 << i))) { irq[i] = -1; @@ -995,13 +1322,17 @@ static int bcm2835_dma_probe(struct plat irq[i] = platform_get_irq(pdev, i < 11 ? i : 11); } + chan_count = 0; + /* get irqs for each channel */ - for (i = 0; i <= BCM2835_DMA_MAX_DMA_CHAN_SUPPORTED; i++) { + for (i = chan_start; i < chan_end; i++) { /* skip channels without irq */ if (irq[i] < 0) continue; /* check if there are other channels that also use this irq */ + /* FIXME: This will fail if interrupts are shared across + instances */ irq_flags = 0; for (j = 0; j <= BCM2835_DMA_MAX_DMA_CHAN_SUPPORTED; j++) if ((i != j) && (irq[j] == irq[i])) { @@ -1013,9 +1344,10 @@ static int bcm2835_dma_probe(struct plat rc = bcm2835_dma_chan_init(od, i, irq[i], irq_flags); if (rc) goto err_no_dma; + chan_count++; } - dev_dbg(&pdev->dev, "Initialized %i DMA channels\n", i); + dev_dbg(&pdev->dev, "Initialized %i DMA channels\n", chan_count); /* Device-tree DMA controller registration */ rc = of_dma_controller_register(pdev->dev.of_node, @@ -1047,6 +1379,13 @@ static int bcm2835_dma_remove(struct pla bcm_dmaman_remove(pdev); dma_async_device_unregister(&od->ddev); + if (memcpy_parent == od) { + dma_free_coherent(&pdev->dev, sizeof(*memcpy_scb), memcpy_scb, + memcpy_scb_dma); + memcpy_parent = NULL; + memcpy_scb = NULL; + memcpy_chan = NULL; + } bcm2835_dma_free(od); return 0;