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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/dma/stm32-mdma.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/dma/stm32-mdma.c')
-rw-r--r-- | drivers/dma/stm32-mdma.c | 1834 |
1 files changed, 1834 insertions, 0 deletions
diff --git a/drivers/dma/stm32-mdma.c b/drivers/dma/stm32-mdma.c new file mode 100644 index 000000000..65ef1f5ca --- /dev/null +++ b/drivers/dma/stm32-mdma.c @@ -0,0 +1,1834 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * + * Copyright (C) STMicroelectronics SA 2017 + * Author(s): M'boumba Cedric Madianga <cedric.madianga@gmail.com> + * Pierre-Yves Mordret <pierre-yves.mordret@st.com> + * + * Driver for STM32 MDMA controller + * + * Inspired by stm32-dma.c and dma-jz4780.c + */ + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/dmapool.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/iopoll.h> +#include <linux/jiffies.h> +#include <linux/list.h> +#include <linux/log2.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_dma.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/reset.h> +#include <linux/slab.h> + +#include "virt-dma.h" + +#define STM32_MDMA_GISR0 0x0000 /* MDMA Int Status Reg 1 */ + +/* MDMA Channel x interrupt/status register */ +#define STM32_MDMA_CISR(x) (0x40 + 0x40 * (x)) /* x = 0..62 */ +#define STM32_MDMA_CISR_CRQA BIT(16) +#define STM32_MDMA_CISR_TCIF BIT(4) +#define STM32_MDMA_CISR_BTIF BIT(3) +#define STM32_MDMA_CISR_BRTIF BIT(2) +#define STM32_MDMA_CISR_CTCIF BIT(1) +#define STM32_MDMA_CISR_TEIF BIT(0) + +/* MDMA Channel x interrupt flag clear register */ +#define STM32_MDMA_CIFCR(x) (0x44 + 0x40 * (x)) +#define STM32_MDMA_CIFCR_CLTCIF BIT(4) +#define STM32_MDMA_CIFCR_CBTIF BIT(3) +#define STM32_MDMA_CIFCR_CBRTIF BIT(2) +#define STM32_MDMA_CIFCR_CCTCIF BIT(1) +#define STM32_MDMA_CIFCR_CTEIF BIT(0) +#define STM32_MDMA_CIFCR_CLEAR_ALL (STM32_MDMA_CIFCR_CLTCIF \ + | STM32_MDMA_CIFCR_CBTIF \ + | STM32_MDMA_CIFCR_CBRTIF \ + | STM32_MDMA_CIFCR_CCTCIF \ + | STM32_MDMA_CIFCR_CTEIF) + +/* MDMA Channel x error status register */ +#define STM32_MDMA_CESR(x) (0x48 + 0x40 * (x)) +#define STM32_MDMA_CESR_BSE BIT(11) +#define STM32_MDMA_CESR_ASR BIT(10) +#define STM32_MDMA_CESR_TEMD BIT(9) +#define STM32_MDMA_CESR_TELD BIT(8) +#define STM32_MDMA_CESR_TED BIT(7) +#define STM32_MDMA_CESR_TEA_MASK GENMASK(6, 0) + +/* MDMA Channel x control register */ +#define STM32_MDMA_CCR(x) (0x4C + 0x40 * (x)) +#define STM32_MDMA_CCR_SWRQ BIT(16) +#define STM32_MDMA_CCR_WEX BIT(14) +#define STM32_MDMA_CCR_HEX BIT(13) +#define STM32_MDMA_CCR_BEX BIT(12) +#define STM32_MDMA_CCR_SM BIT(8) +#define STM32_MDMA_CCR_PL_MASK GENMASK(7, 6) +#define STM32_MDMA_CCR_PL(n) FIELD_PREP(STM32_MDMA_CCR_PL_MASK, (n)) +#define STM32_MDMA_CCR_TCIE BIT(5) +#define STM32_MDMA_CCR_BTIE BIT(4) +#define STM32_MDMA_CCR_BRTIE BIT(3) +#define STM32_MDMA_CCR_CTCIE BIT(2) +#define STM32_MDMA_CCR_TEIE BIT(1) +#define STM32_MDMA_CCR_EN BIT(0) +#define STM32_MDMA_CCR_IRQ_MASK (STM32_MDMA_CCR_TCIE \ + | STM32_MDMA_CCR_BTIE \ + | STM32_MDMA_CCR_BRTIE \ + | STM32_MDMA_CCR_CTCIE \ + | STM32_MDMA_CCR_TEIE) + +/* MDMA Channel x transfer configuration register */ +#define STM32_MDMA_CTCR(x) (0x50 + 0x40 * (x)) +#define STM32_MDMA_CTCR_BWM BIT(31) +#define STM32_MDMA_CTCR_SWRM BIT(30) +#define STM32_MDMA_CTCR_TRGM_MSK GENMASK(29, 28) +#define STM32_MDMA_CTCR_TRGM(n) FIELD_PREP(STM32_MDMA_CTCR_TRGM_MSK, (n)) +#define STM32_MDMA_CTCR_TRGM_GET(n) FIELD_GET(STM32_MDMA_CTCR_TRGM_MSK, (n)) +#define STM32_MDMA_CTCR_PAM_MASK GENMASK(27, 26) +#define STM32_MDMA_CTCR_PAM(n) FIELD_PREP(STM32_MDMA_CTCR_PAM_MASK, (n)) +#define STM32_MDMA_CTCR_PKE BIT(25) +#define STM32_MDMA_CTCR_TLEN_MSK GENMASK(24, 18) +#define STM32_MDMA_CTCR_TLEN(n) FIELD_PREP(STM32_MDMA_CTCR_TLEN_MSK, (n)) +#define STM32_MDMA_CTCR_TLEN_GET(n) FIELD_GET(STM32_MDMA_CTCR_TLEN_MSK, (n)) +#define STM32_MDMA_CTCR_LEN2_MSK GENMASK(25, 18) +#define STM32_MDMA_CTCR_LEN2(n) FIELD_PREP(STM32_MDMA_CTCR_LEN2_MSK, (n)) +#define STM32_MDMA_CTCR_LEN2_GET(n) FIELD_GET(STM32_MDMA_CTCR_LEN2_MSK, (n)) +#define STM32_MDMA_CTCR_DBURST_MASK GENMASK(17, 15) +#define STM32_MDMA_CTCR_DBURST(n) FIELD_PREP(STM32_MDMA_CTCR_DBURST_MASK, (n)) +#define STM32_MDMA_CTCR_SBURST_MASK GENMASK(14, 12) +#define STM32_MDMA_CTCR_SBURST(n) FIELD_PREP(STM32_MDMA_CTCR_SBURST_MASK, (n)) +#define STM32_MDMA_CTCR_DINCOS_MASK GENMASK(11, 10) +#define STM32_MDMA_CTCR_DINCOS(n) FIELD_PREP(STM32_MDMA_CTCR_DINCOS_MASK, (n)) +#define STM32_MDMA_CTCR_SINCOS_MASK GENMASK(9, 8) +#define STM32_MDMA_CTCR_SINCOS(n) FIELD_PREP(STM32_MDMA_CTCR_SINCOS_MASK, (n)) +#define STM32_MDMA_CTCR_DSIZE_MASK GENMASK(7, 6) +#define STM32_MDMA_CTCR_DSIZE(n) FIELD_PREP(STM32_MDMA_CTCR_DSIZE_MASK, (n)) +#define STM32_MDMA_CTCR_SSIZE_MASK GENMASK(5, 4) +#define STM32_MDMA_CTCR_SSIZE(n) FIELD_PREP(STM32_MDMA_CTCR_SSIZE_MASK, (n)) +#define STM32_MDMA_CTCR_DINC_MASK GENMASK(3, 2) +#define STM32_MDMA_CTCR_DINC(n) FIELD_PREP(STM32_MDMA_CTCR_DINC_MASK, (n)) +#define STM32_MDMA_CTCR_SINC_MASK GENMASK(1, 0) +#define STM32_MDMA_CTCR_SINC(n) FIELD_PREP(STM32_MDMA_CTCR_SINC_MASK, (n)) +#define STM32_MDMA_CTCR_CFG_MASK (STM32_MDMA_CTCR_SINC_MASK \ + | STM32_MDMA_CTCR_DINC_MASK \ + | STM32_MDMA_CTCR_SINCOS_MASK \ + | STM32_MDMA_CTCR_DINCOS_MASK \ + | STM32_MDMA_CTCR_LEN2_MSK \ + | STM32_MDMA_CTCR_TRGM_MSK) + +/* MDMA Channel x block number of data register */ +#define STM32_MDMA_CBNDTR(x) (0x54 + 0x40 * (x)) +#define STM32_MDMA_CBNDTR_BRC_MK GENMASK(31, 20) +#define STM32_MDMA_CBNDTR_BRC(n) FIELD_PREP(STM32_MDMA_CBNDTR_BRC_MK, (n)) +#define STM32_MDMA_CBNDTR_BRC_GET(n) FIELD_GET(STM32_MDMA_CBNDTR_BRC_MK, (n)) + +#define STM32_MDMA_CBNDTR_BRDUM BIT(19) +#define STM32_MDMA_CBNDTR_BRSUM BIT(18) +#define STM32_MDMA_CBNDTR_BNDT_MASK GENMASK(16, 0) +#define STM32_MDMA_CBNDTR_BNDT(n) FIELD_PREP(STM32_MDMA_CBNDTR_BNDT_MASK, (n)) + +/* MDMA Channel x source address register */ +#define STM32_MDMA_CSAR(x) (0x58 + 0x40 * (x)) + +/* MDMA Channel x destination address register */ +#define STM32_MDMA_CDAR(x) (0x5C + 0x40 * (x)) + +/* MDMA Channel x block repeat address update register */ +#define STM32_MDMA_CBRUR(x) (0x60 + 0x40 * (x)) +#define STM32_MDMA_CBRUR_DUV_MASK GENMASK(31, 16) +#define STM32_MDMA_CBRUR_DUV(n) FIELD_PREP(STM32_MDMA_CBRUR_DUV_MASK, (n)) +#define STM32_MDMA_CBRUR_SUV_MASK GENMASK(15, 0) +#define STM32_MDMA_CBRUR_SUV(n) FIELD_PREP(STM32_MDMA_CBRUR_SUV_MASK, (n)) + +/* MDMA Channel x link address register */ +#define STM32_MDMA_CLAR(x) (0x64 + 0x40 * (x)) + +/* MDMA Channel x trigger and bus selection register */ +#define STM32_MDMA_CTBR(x) (0x68 + 0x40 * (x)) +#define STM32_MDMA_CTBR_DBUS BIT(17) +#define STM32_MDMA_CTBR_SBUS BIT(16) +#define STM32_MDMA_CTBR_TSEL_MASK GENMASK(5, 0) +#define STM32_MDMA_CTBR_TSEL(n) FIELD_PREP(STM32_MDMA_CTBR_TSEL_MASK, (n)) + +/* MDMA Channel x mask address register */ +#define STM32_MDMA_CMAR(x) (0x70 + 0x40 * (x)) + +/* MDMA Channel x mask data register */ +#define STM32_MDMA_CMDR(x) (0x74 + 0x40 * (x)) + +#define STM32_MDMA_MAX_BUF_LEN 128 +#define STM32_MDMA_MAX_BLOCK_LEN 65536 +#define STM32_MDMA_MAX_CHANNELS 32 +#define STM32_MDMA_MAX_REQUESTS 256 +#define STM32_MDMA_MAX_BURST 128 +#define STM32_MDMA_VERY_HIGH_PRIORITY 0x3 + +enum stm32_mdma_trigger_mode { + STM32_MDMA_BUFFER, + STM32_MDMA_BLOCK, + STM32_MDMA_BLOCK_REP, + STM32_MDMA_LINKED_LIST, +}; + +enum stm32_mdma_width { + STM32_MDMA_BYTE, + STM32_MDMA_HALF_WORD, + STM32_MDMA_WORD, + STM32_MDMA_DOUBLE_WORD, +}; + +enum stm32_mdma_inc_mode { + STM32_MDMA_FIXED = 0, + STM32_MDMA_INC = 2, + STM32_MDMA_DEC = 3, +}; + +struct stm32_mdma_chan_config { + u32 request; + u32 priority_level; + u32 transfer_config; + u32 mask_addr; + u32 mask_data; + bool m2m_hw; /* True when MDMA is triggered by STM32 DMA */ +}; + +struct stm32_mdma_hwdesc { + u32 ctcr; + u32 cbndtr; + u32 csar; + u32 cdar; + u32 cbrur; + u32 clar; + u32 ctbr; + u32 dummy; + u32 cmar; + u32 cmdr; +} __aligned(64); + +struct stm32_mdma_desc_node { + struct stm32_mdma_hwdesc *hwdesc; + dma_addr_t hwdesc_phys; +}; + +struct stm32_mdma_desc { + struct virt_dma_desc vdesc; + u32 ccr; + bool cyclic; + u32 count; + struct stm32_mdma_desc_node node[]; +}; + +struct stm32_mdma_dma_config { + u32 request; /* STM32 DMA channel stream id, triggering MDMA */ + u32 cmar; /* STM32 DMA interrupt flag clear register address */ + u32 cmdr; /* STM32 DMA Transfer Complete flag */ +}; + +struct stm32_mdma_chan { + struct virt_dma_chan vchan; + struct dma_pool *desc_pool; + u32 id; + struct stm32_mdma_desc *desc; + u32 curr_hwdesc; + struct dma_slave_config dma_config; + struct stm32_mdma_chan_config chan_config; + bool busy; + u32 mem_burst; + u32 mem_width; +}; + +struct stm32_mdma_device { + struct dma_device ddev; + void __iomem *base; + struct clk *clk; + int irq; + u32 nr_channels; + u32 nr_requests; + u32 nr_ahb_addr_masks; + u32 chan_reserved; + struct stm32_mdma_chan chan[STM32_MDMA_MAX_CHANNELS]; + u32 ahb_addr_masks[]; +}; + +static struct stm32_mdma_device *stm32_mdma_get_dev( + struct stm32_mdma_chan *chan) +{ + return container_of(chan->vchan.chan.device, struct stm32_mdma_device, + ddev); +} + +static struct stm32_mdma_chan *to_stm32_mdma_chan(struct dma_chan *c) +{ + return container_of(c, struct stm32_mdma_chan, vchan.chan); +} + +static struct stm32_mdma_desc *to_stm32_mdma_desc(struct virt_dma_desc *vdesc) +{ + return container_of(vdesc, struct stm32_mdma_desc, vdesc); +} + +static struct device *chan2dev(struct stm32_mdma_chan *chan) +{ + return &chan->vchan.chan.dev->device; +} + +static struct device *mdma2dev(struct stm32_mdma_device *mdma_dev) +{ + return mdma_dev->ddev.dev; +} + +static u32 stm32_mdma_read(struct stm32_mdma_device *dmadev, u32 reg) +{ + return readl_relaxed(dmadev->base + reg); +} + +static void stm32_mdma_write(struct stm32_mdma_device *dmadev, u32 reg, u32 val) +{ + writel_relaxed(val, dmadev->base + reg); +} + +static void stm32_mdma_set_bits(struct stm32_mdma_device *dmadev, u32 reg, + u32 mask) +{ + void __iomem *addr = dmadev->base + reg; + + writel_relaxed(readl_relaxed(addr) | mask, addr); +} + +static void stm32_mdma_clr_bits(struct stm32_mdma_device *dmadev, u32 reg, + u32 mask) +{ + void __iomem *addr = dmadev->base + reg; + + writel_relaxed(readl_relaxed(addr) & ~mask, addr); +} + +static struct stm32_mdma_desc *stm32_mdma_alloc_desc( + struct stm32_mdma_chan *chan, u32 count) +{ + struct stm32_mdma_desc *desc; + int i; + + desc = kzalloc(struct_size(desc, node, count), GFP_NOWAIT); + if (!desc) + return NULL; + + for (i = 0; i < count; i++) { + desc->node[i].hwdesc = + dma_pool_alloc(chan->desc_pool, GFP_NOWAIT, + &desc->node[i].hwdesc_phys); + if (!desc->node[i].hwdesc) + goto err; + } + + desc->count = count; + + return desc; + +err: + dev_err(chan2dev(chan), "Failed to allocate descriptor\n"); + while (--i >= 0) + dma_pool_free(chan->desc_pool, desc->node[i].hwdesc, + desc->node[i].hwdesc_phys); + kfree(desc); + return NULL; +} + +static void stm32_mdma_desc_free(struct virt_dma_desc *vdesc) +{ + struct stm32_mdma_desc *desc = to_stm32_mdma_desc(vdesc); + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(vdesc->tx.chan); + int i; + + for (i = 0; i < desc->count; i++) + dma_pool_free(chan->desc_pool, desc->node[i].hwdesc, + desc->node[i].hwdesc_phys); + kfree(desc); +} + +static int stm32_mdma_get_width(struct stm32_mdma_chan *chan, + enum dma_slave_buswidth width) +{ + switch (width) { + case DMA_SLAVE_BUSWIDTH_1_BYTE: + case DMA_SLAVE_BUSWIDTH_2_BYTES: + case DMA_SLAVE_BUSWIDTH_4_BYTES: + case DMA_SLAVE_BUSWIDTH_8_BYTES: + return ffs(width) - 1; + default: + dev_err(chan2dev(chan), "Dma bus width %i not supported\n", + width); + return -EINVAL; + } +} + +static enum dma_slave_buswidth stm32_mdma_get_max_width(dma_addr_t addr, + u32 buf_len, u32 tlen) +{ + enum dma_slave_buswidth max_width = DMA_SLAVE_BUSWIDTH_8_BYTES; + + for (max_width = DMA_SLAVE_BUSWIDTH_8_BYTES; + max_width > DMA_SLAVE_BUSWIDTH_1_BYTE; + max_width >>= 1) { + /* + * Address and buffer length both have to be aligned on + * bus width + */ + if ((((buf_len | addr) & (max_width - 1)) == 0) && + tlen >= max_width) + break; + } + + return max_width; +} + +static u32 stm32_mdma_get_best_burst(u32 buf_len, u32 tlen, u32 max_burst, + enum dma_slave_buswidth width) +{ + u32 best_burst; + + best_burst = min((u32)1 << __ffs(tlen | buf_len), + max_burst * width) / width; + + return (best_burst > 0) ? best_burst : 1; +} + +static int stm32_mdma_disable_chan(struct stm32_mdma_chan *chan) +{ + struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan); + u32 ccr, cisr, id, reg; + int ret; + + id = chan->id; + reg = STM32_MDMA_CCR(id); + + /* Disable interrupts */ + stm32_mdma_clr_bits(dmadev, reg, STM32_MDMA_CCR_IRQ_MASK); + + ccr = stm32_mdma_read(dmadev, reg); + if (ccr & STM32_MDMA_CCR_EN) { + stm32_mdma_clr_bits(dmadev, reg, STM32_MDMA_CCR_EN); + + /* Ensure that any ongoing transfer has been completed */ + ret = readl_relaxed_poll_timeout_atomic( + dmadev->base + STM32_MDMA_CISR(id), cisr, + (cisr & STM32_MDMA_CISR_CTCIF), 10, 1000); + if (ret) { + dev_err(chan2dev(chan), "%s: timeout!\n", __func__); + return -EBUSY; + } + } + + return 0; +} + +static void stm32_mdma_stop(struct stm32_mdma_chan *chan) +{ + struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan); + u32 status; + int ret; + + /* Disable DMA */ + ret = stm32_mdma_disable_chan(chan); + if (ret < 0) + return; + + /* Clear interrupt status if it is there */ + status = stm32_mdma_read(dmadev, STM32_MDMA_CISR(chan->id)); + if (status) { + dev_dbg(chan2dev(chan), "%s(): clearing interrupt: 0x%08x\n", + __func__, status); + stm32_mdma_set_bits(dmadev, STM32_MDMA_CIFCR(chan->id), status); + } + + chan->busy = false; +} + +static void stm32_mdma_set_bus(struct stm32_mdma_device *dmadev, u32 *ctbr, + u32 ctbr_mask, u32 src_addr) +{ + u32 mask; + int i; + + /* Check if memory device is on AHB or AXI */ + *ctbr &= ~ctbr_mask; + mask = src_addr & 0xF0000000; + for (i = 0; i < dmadev->nr_ahb_addr_masks; i++) { + if (mask == dmadev->ahb_addr_masks[i]) { + *ctbr |= ctbr_mask; + break; + } + } +} + +static int stm32_mdma_set_xfer_param(struct stm32_mdma_chan *chan, + enum dma_transfer_direction direction, + u32 *mdma_ccr, u32 *mdma_ctcr, + u32 *mdma_ctbr, dma_addr_t addr, + u32 buf_len) +{ + struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan); + struct stm32_mdma_chan_config *chan_config = &chan->chan_config; + enum dma_slave_buswidth src_addr_width, dst_addr_width; + phys_addr_t src_addr, dst_addr; + int src_bus_width, dst_bus_width; + u32 src_maxburst, dst_maxburst, src_best_burst, dst_best_burst; + u32 ccr, ctcr, ctbr, tlen; + + src_addr_width = chan->dma_config.src_addr_width; + dst_addr_width = chan->dma_config.dst_addr_width; + src_maxburst = chan->dma_config.src_maxburst; + dst_maxburst = chan->dma_config.dst_maxburst; + + ccr = stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id)) & ~STM32_MDMA_CCR_EN; + ctcr = stm32_mdma_read(dmadev, STM32_MDMA_CTCR(chan->id)); + ctbr = stm32_mdma_read(dmadev, STM32_MDMA_CTBR(chan->id)); + + /* Enable HW request mode */ + ctcr &= ~STM32_MDMA_CTCR_SWRM; + + /* Set DINC, SINC, DINCOS, SINCOS, TRGM and TLEN retrieve from DT */ + ctcr &= ~STM32_MDMA_CTCR_CFG_MASK; + ctcr |= chan_config->transfer_config & STM32_MDMA_CTCR_CFG_MASK; + + /* + * For buffer transfer length (TLEN) we have to set + * the number of bytes - 1 in CTCR register + */ + tlen = STM32_MDMA_CTCR_LEN2_GET(ctcr); + ctcr &= ~STM32_MDMA_CTCR_LEN2_MSK; + ctcr |= STM32_MDMA_CTCR_TLEN((tlen - 1)); + + /* Disable Pack Enable */ + ctcr &= ~STM32_MDMA_CTCR_PKE; + + /* Check burst size constraints */ + if (src_maxburst * src_addr_width > STM32_MDMA_MAX_BURST || + dst_maxburst * dst_addr_width > STM32_MDMA_MAX_BURST) { + dev_err(chan2dev(chan), + "burst size * bus width higher than %d bytes\n", + STM32_MDMA_MAX_BURST); + return -EINVAL; + } + + if ((!is_power_of_2(src_maxburst) && src_maxburst > 0) || + (!is_power_of_2(dst_maxburst) && dst_maxburst > 0)) { + dev_err(chan2dev(chan), "burst size must be a power of 2\n"); + return -EINVAL; + } + + /* + * Configure channel control: + * - Clear SW request as in this case this is a HW one + * - Clear WEX, HEX and BEX bits + * - Set priority level + */ + ccr &= ~(STM32_MDMA_CCR_SWRQ | STM32_MDMA_CCR_WEX | STM32_MDMA_CCR_HEX | + STM32_MDMA_CCR_BEX | STM32_MDMA_CCR_PL_MASK); + ccr |= STM32_MDMA_CCR_PL(chan_config->priority_level); + + /* Configure Trigger selection */ + ctbr &= ~STM32_MDMA_CTBR_TSEL_MASK; + ctbr |= STM32_MDMA_CTBR_TSEL(chan_config->request); + + switch (direction) { + case DMA_MEM_TO_DEV: + dst_addr = chan->dma_config.dst_addr; + + /* Set device data size */ + if (chan_config->m2m_hw) + dst_addr_width = stm32_mdma_get_max_width(dst_addr, buf_len, + STM32_MDMA_MAX_BUF_LEN); + dst_bus_width = stm32_mdma_get_width(chan, dst_addr_width); + if (dst_bus_width < 0) + return dst_bus_width; + ctcr &= ~STM32_MDMA_CTCR_DSIZE_MASK; + ctcr |= STM32_MDMA_CTCR_DSIZE(dst_bus_width); + if (chan_config->m2m_hw) { + ctcr &= ~STM32_MDMA_CTCR_DINCOS_MASK; + ctcr |= STM32_MDMA_CTCR_DINCOS(dst_bus_width); + } + + /* Set device burst value */ + if (chan_config->m2m_hw) + dst_maxburst = STM32_MDMA_MAX_BUF_LEN / dst_addr_width; + + dst_best_burst = stm32_mdma_get_best_burst(buf_len, tlen, + dst_maxburst, + dst_addr_width); + chan->mem_burst = dst_best_burst; + ctcr &= ~STM32_MDMA_CTCR_DBURST_MASK; + ctcr |= STM32_MDMA_CTCR_DBURST((ilog2(dst_best_burst))); + + /* Set memory data size */ + src_addr_width = stm32_mdma_get_max_width(addr, buf_len, tlen); + chan->mem_width = src_addr_width; + src_bus_width = stm32_mdma_get_width(chan, src_addr_width); + if (src_bus_width < 0) + return src_bus_width; + ctcr &= ~STM32_MDMA_CTCR_SSIZE_MASK | + STM32_MDMA_CTCR_SINCOS_MASK; + ctcr |= STM32_MDMA_CTCR_SSIZE(src_bus_width) | + STM32_MDMA_CTCR_SINCOS(src_bus_width); + + /* Set memory burst value */ + src_maxburst = STM32_MDMA_MAX_BUF_LEN / src_addr_width; + src_best_burst = stm32_mdma_get_best_burst(buf_len, tlen, + src_maxburst, + src_addr_width); + chan->mem_burst = src_best_burst; + ctcr &= ~STM32_MDMA_CTCR_SBURST_MASK; + ctcr |= STM32_MDMA_CTCR_SBURST((ilog2(src_best_burst))); + + /* Select bus */ + stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_DBUS, + dst_addr); + + if (dst_bus_width != src_bus_width) + ctcr |= STM32_MDMA_CTCR_PKE; + + /* Set destination address */ + stm32_mdma_write(dmadev, STM32_MDMA_CDAR(chan->id), dst_addr); + break; + + case DMA_DEV_TO_MEM: + src_addr = chan->dma_config.src_addr; + + /* Set device data size */ + if (chan_config->m2m_hw) + src_addr_width = stm32_mdma_get_max_width(src_addr, buf_len, + STM32_MDMA_MAX_BUF_LEN); + + src_bus_width = stm32_mdma_get_width(chan, src_addr_width); + if (src_bus_width < 0) + return src_bus_width; + ctcr &= ~STM32_MDMA_CTCR_SSIZE_MASK; + ctcr |= STM32_MDMA_CTCR_SSIZE(src_bus_width); + if (chan_config->m2m_hw) { + ctcr &= ~STM32_MDMA_CTCR_SINCOS_MASK; + ctcr |= STM32_MDMA_CTCR_SINCOS(src_bus_width); + } + + /* Set device burst value */ + if (chan_config->m2m_hw) + src_maxburst = STM32_MDMA_MAX_BUF_LEN / src_addr_width; + + src_best_burst = stm32_mdma_get_best_burst(buf_len, tlen, + src_maxburst, + src_addr_width); + ctcr &= ~STM32_MDMA_CTCR_SBURST_MASK; + ctcr |= STM32_MDMA_CTCR_SBURST((ilog2(src_best_burst))); + + /* Set memory data size */ + dst_addr_width = stm32_mdma_get_max_width(addr, buf_len, tlen); + chan->mem_width = dst_addr_width; + dst_bus_width = stm32_mdma_get_width(chan, dst_addr_width); + if (dst_bus_width < 0) + return dst_bus_width; + ctcr &= ~(STM32_MDMA_CTCR_DSIZE_MASK | + STM32_MDMA_CTCR_DINCOS_MASK); + ctcr |= STM32_MDMA_CTCR_DSIZE(dst_bus_width) | + STM32_MDMA_CTCR_DINCOS(dst_bus_width); + + /* Set memory burst value */ + dst_maxburst = STM32_MDMA_MAX_BUF_LEN / dst_addr_width; + dst_best_burst = stm32_mdma_get_best_burst(buf_len, tlen, + dst_maxburst, + dst_addr_width); + ctcr &= ~STM32_MDMA_CTCR_DBURST_MASK; + ctcr |= STM32_MDMA_CTCR_DBURST((ilog2(dst_best_burst))); + + /* Select bus */ + stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_SBUS, + src_addr); + + if (dst_bus_width != src_bus_width) + ctcr |= STM32_MDMA_CTCR_PKE; + + /* Set source address */ + stm32_mdma_write(dmadev, STM32_MDMA_CSAR(chan->id), src_addr); + break; + + default: + dev_err(chan2dev(chan), "Dma direction is not supported\n"); + return -EINVAL; + } + + *mdma_ccr = ccr; + *mdma_ctcr = ctcr; + *mdma_ctbr = ctbr; + + return 0; +} + +static void stm32_mdma_dump_hwdesc(struct stm32_mdma_chan *chan, + struct stm32_mdma_desc_node *node) +{ + dev_dbg(chan2dev(chan), "hwdesc: %pad\n", &node->hwdesc_phys); + dev_dbg(chan2dev(chan), "CTCR: 0x%08x\n", node->hwdesc->ctcr); + dev_dbg(chan2dev(chan), "CBNDTR: 0x%08x\n", node->hwdesc->cbndtr); + dev_dbg(chan2dev(chan), "CSAR: 0x%08x\n", node->hwdesc->csar); + dev_dbg(chan2dev(chan), "CDAR: 0x%08x\n", node->hwdesc->cdar); + dev_dbg(chan2dev(chan), "CBRUR: 0x%08x\n", node->hwdesc->cbrur); + dev_dbg(chan2dev(chan), "CLAR: 0x%08x\n", node->hwdesc->clar); + dev_dbg(chan2dev(chan), "CTBR: 0x%08x\n", node->hwdesc->ctbr); + dev_dbg(chan2dev(chan), "CMAR: 0x%08x\n", node->hwdesc->cmar); + dev_dbg(chan2dev(chan), "CMDR: 0x%08x\n\n", node->hwdesc->cmdr); +} + +static void stm32_mdma_setup_hwdesc(struct stm32_mdma_chan *chan, + struct stm32_mdma_desc *desc, + enum dma_transfer_direction dir, u32 count, + dma_addr_t src_addr, dma_addr_t dst_addr, + u32 len, u32 ctcr, u32 ctbr, bool is_last, + bool is_first, bool is_cyclic) +{ + struct stm32_mdma_chan_config *config = &chan->chan_config; + struct stm32_mdma_hwdesc *hwdesc; + u32 next = count + 1; + + hwdesc = desc->node[count].hwdesc; + hwdesc->ctcr = ctcr; + hwdesc->cbndtr &= ~(STM32_MDMA_CBNDTR_BRC_MK | + STM32_MDMA_CBNDTR_BRDUM | + STM32_MDMA_CBNDTR_BRSUM | + STM32_MDMA_CBNDTR_BNDT_MASK); + hwdesc->cbndtr |= STM32_MDMA_CBNDTR_BNDT(len); + hwdesc->csar = src_addr; + hwdesc->cdar = dst_addr; + hwdesc->cbrur = 0; + hwdesc->ctbr = ctbr; + hwdesc->cmar = config->mask_addr; + hwdesc->cmdr = config->mask_data; + + if (is_last) { + if (is_cyclic) + hwdesc->clar = desc->node[0].hwdesc_phys; + else + hwdesc->clar = 0; + } else { + hwdesc->clar = desc->node[next].hwdesc_phys; + } + + stm32_mdma_dump_hwdesc(chan, &desc->node[count]); +} + +static int stm32_mdma_setup_xfer(struct stm32_mdma_chan *chan, + struct stm32_mdma_desc *desc, + struct scatterlist *sgl, u32 sg_len, + enum dma_transfer_direction direction) +{ + struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan); + struct dma_slave_config *dma_config = &chan->dma_config; + struct stm32_mdma_chan_config *chan_config = &chan->chan_config; + struct scatterlist *sg; + dma_addr_t src_addr, dst_addr; + u32 m2m_hw_period, ccr, ctcr, ctbr; + int i, ret = 0; + + if (chan_config->m2m_hw) + m2m_hw_period = sg_dma_len(sgl); + + for_each_sg(sgl, sg, sg_len, i) { + if (sg_dma_len(sg) > STM32_MDMA_MAX_BLOCK_LEN) { + dev_err(chan2dev(chan), "Invalid block len\n"); + return -EINVAL; + } + + if (direction == DMA_MEM_TO_DEV) { + src_addr = sg_dma_address(sg); + dst_addr = dma_config->dst_addr; + if (chan_config->m2m_hw && (i & 1)) + dst_addr += m2m_hw_period; + ret = stm32_mdma_set_xfer_param(chan, direction, &ccr, + &ctcr, &ctbr, src_addr, + sg_dma_len(sg)); + stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_SBUS, + src_addr); + } else { + src_addr = dma_config->src_addr; + if (chan_config->m2m_hw && (i & 1)) + src_addr += m2m_hw_period; + dst_addr = sg_dma_address(sg); + ret = stm32_mdma_set_xfer_param(chan, direction, &ccr, + &ctcr, &ctbr, dst_addr, + sg_dma_len(sg)); + stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_DBUS, + dst_addr); + } + + if (ret < 0) + return ret; + + stm32_mdma_setup_hwdesc(chan, desc, direction, i, src_addr, + dst_addr, sg_dma_len(sg), ctcr, ctbr, + i == sg_len - 1, i == 0, false); + } + + /* Enable interrupts */ + ccr &= ~STM32_MDMA_CCR_IRQ_MASK; + ccr |= STM32_MDMA_CCR_TEIE | STM32_MDMA_CCR_CTCIE; + desc->ccr = ccr; + + return 0; +} + +static struct dma_async_tx_descriptor * +stm32_mdma_prep_slave_sg(struct dma_chan *c, struct scatterlist *sgl, + u32 sg_len, enum dma_transfer_direction direction, + unsigned long flags, void *context) +{ + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c); + struct stm32_mdma_chan_config *chan_config = &chan->chan_config; + struct stm32_mdma_desc *desc; + int i, ret; + + /* + * Once DMA is in setup cyclic mode the channel we cannot assign this + * channel anymore. The DMA channel needs to be aborted or terminated + * for allowing another request. + */ + if (chan->desc && chan->desc->cyclic) { + dev_err(chan2dev(chan), + "Request not allowed when dma in cyclic mode\n"); + return NULL; + } + + desc = stm32_mdma_alloc_desc(chan, sg_len); + if (!desc) + return NULL; + + ret = stm32_mdma_setup_xfer(chan, desc, sgl, sg_len, direction); + if (ret < 0) + goto xfer_setup_err; + + /* + * In case of M2M HW transfer triggered by STM32 DMA, we do not have to clear the + * transfer complete flag by hardware in order to let the CPU rearm the STM32 DMA + * with the next sg element and update some data in dmaengine framework. + */ + if (chan_config->m2m_hw && direction == DMA_MEM_TO_DEV) { + struct stm32_mdma_hwdesc *hwdesc; + + for (i = 0; i < sg_len; i++) { + hwdesc = desc->node[i].hwdesc; + hwdesc->cmar = 0; + hwdesc->cmdr = 0; + } + } + + desc->cyclic = false; + + return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags); + +xfer_setup_err: + for (i = 0; i < desc->count; i++) + dma_pool_free(chan->desc_pool, desc->node[i].hwdesc, + desc->node[i].hwdesc_phys); + kfree(desc); + return NULL; +} + +static struct dma_async_tx_descriptor * +stm32_mdma_prep_dma_cyclic(struct dma_chan *c, dma_addr_t buf_addr, + size_t buf_len, size_t period_len, + enum dma_transfer_direction direction, + unsigned long flags) +{ + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c); + struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan); + struct dma_slave_config *dma_config = &chan->dma_config; + struct stm32_mdma_chan_config *chan_config = &chan->chan_config; + struct stm32_mdma_desc *desc; + dma_addr_t src_addr, dst_addr; + u32 ccr, ctcr, ctbr, count; + int i, ret; + + /* + * Once DMA is in setup cyclic mode the channel we cannot assign this + * channel anymore. The DMA channel needs to be aborted or terminated + * for allowing another request. + */ + if (chan->desc && chan->desc->cyclic) { + dev_err(chan2dev(chan), + "Request not allowed when dma in cyclic mode\n"); + return NULL; + } + + if (!buf_len || !period_len || period_len > STM32_MDMA_MAX_BLOCK_LEN) { + dev_err(chan2dev(chan), "Invalid buffer/period len\n"); + return NULL; + } + + if (buf_len % period_len) { + dev_err(chan2dev(chan), "buf_len not multiple of period_len\n"); + return NULL; + } + + count = buf_len / period_len; + + desc = stm32_mdma_alloc_desc(chan, count); + if (!desc) + return NULL; + + /* Select bus */ + if (direction == DMA_MEM_TO_DEV) { + src_addr = buf_addr; + ret = stm32_mdma_set_xfer_param(chan, direction, &ccr, &ctcr, + &ctbr, src_addr, period_len); + stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_SBUS, + src_addr); + } else { + dst_addr = buf_addr; + ret = stm32_mdma_set_xfer_param(chan, direction, &ccr, &ctcr, + &ctbr, dst_addr, period_len); + stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_DBUS, + dst_addr); + } + + if (ret < 0) + goto xfer_setup_err; + + /* Enable interrupts */ + ccr &= ~STM32_MDMA_CCR_IRQ_MASK; + ccr |= STM32_MDMA_CCR_TEIE | STM32_MDMA_CCR_CTCIE | STM32_MDMA_CCR_BTIE; + desc->ccr = ccr; + + /* Configure hwdesc list */ + for (i = 0; i < count; i++) { + if (direction == DMA_MEM_TO_DEV) { + src_addr = buf_addr + i * period_len; + dst_addr = dma_config->dst_addr; + if (chan_config->m2m_hw && (i & 1)) + dst_addr += period_len; + } else { + src_addr = dma_config->src_addr; + if (chan_config->m2m_hw && (i & 1)) + src_addr += period_len; + dst_addr = buf_addr + i * period_len; + } + + stm32_mdma_setup_hwdesc(chan, desc, direction, i, src_addr, + dst_addr, period_len, ctcr, ctbr, + i == count - 1, i == 0, true); + } + + desc->cyclic = true; + + return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags); + +xfer_setup_err: + for (i = 0; i < desc->count; i++) + dma_pool_free(chan->desc_pool, desc->node[i].hwdesc, + desc->node[i].hwdesc_phys); + kfree(desc); + return NULL; +} + +static struct dma_async_tx_descriptor * +stm32_mdma_prep_dma_memcpy(struct dma_chan *c, dma_addr_t dest, dma_addr_t src, + size_t len, unsigned long flags) +{ + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c); + struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan); + enum dma_slave_buswidth max_width; + struct stm32_mdma_desc *desc; + struct stm32_mdma_hwdesc *hwdesc; + u32 ccr, ctcr, ctbr, cbndtr, count, max_burst, mdma_burst; + u32 best_burst, tlen; + size_t xfer_count, offset; + int src_bus_width, dst_bus_width; + int i; + + /* + * Once DMA is in setup cyclic mode the channel we cannot assign this + * channel anymore. The DMA channel needs to be aborted or terminated + * to allow another request + */ + if (chan->desc && chan->desc->cyclic) { + dev_err(chan2dev(chan), + "Request not allowed when dma in cyclic mode\n"); + return NULL; + } + + count = DIV_ROUND_UP(len, STM32_MDMA_MAX_BLOCK_LEN); + desc = stm32_mdma_alloc_desc(chan, count); + if (!desc) + return NULL; + + ccr = stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id)) & ~STM32_MDMA_CCR_EN; + ctcr = stm32_mdma_read(dmadev, STM32_MDMA_CTCR(chan->id)); + ctbr = stm32_mdma_read(dmadev, STM32_MDMA_CTBR(chan->id)); + cbndtr = stm32_mdma_read(dmadev, STM32_MDMA_CBNDTR(chan->id)); + + /* Enable sw req, some interrupts and clear other bits */ + ccr &= ~(STM32_MDMA_CCR_WEX | STM32_MDMA_CCR_HEX | + STM32_MDMA_CCR_BEX | STM32_MDMA_CCR_PL_MASK | + STM32_MDMA_CCR_IRQ_MASK); + ccr |= STM32_MDMA_CCR_TEIE; + + /* Enable SW request mode, dest/src inc and clear other bits */ + ctcr &= ~(STM32_MDMA_CTCR_BWM | STM32_MDMA_CTCR_TRGM_MSK | + STM32_MDMA_CTCR_PAM_MASK | STM32_MDMA_CTCR_PKE | + STM32_MDMA_CTCR_TLEN_MSK | STM32_MDMA_CTCR_DBURST_MASK | + STM32_MDMA_CTCR_SBURST_MASK | STM32_MDMA_CTCR_DINCOS_MASK | + STM32_MDMA_CTCR_SINCOS_MASK | STM32_MDMA_CTCR_DSIZE_MASK | + STM32_MDMA_CTCR_SSIZE_MASK | STM32_MDMA_CTCR_DINC_MASK | + STM32_MDMA_CTCR_SINC_MASK); + ctcr |= STM32_MDMA_CTCR_SWRM | STM32_MDMA_CTCR_SINC(STM32_MDMA_INC) | + STM32_MDMA_CTCR_DINC(STM32_MDMA_INC); + + /* Reset HW request */ + ctbr &= ~STM32_MDMA_CTBR_TSEL_MASK; + + /* Select bus */ + stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_SBUS, src); + stm32_mdma_set_bus(dmadev, &ctbr, STM32_MDMA_CTBR_DBUS, dest); + + /* Clear CBNDTR registers */ + cbndtr &= ~(STM32_MDMA_CBNDTR_BRC_MK | STM32_MDMA_CBNDTR_BRDUM | + STM32_MDMA_CBNDTR_BRSUM | STM32_MDMA_CBNDTR_BNDT_MASK); + + if (len <= STM32_MDMA_MAX_BLOCK_LEN) { + cbndtr |= STM32_MDMA_CBNDTR_BNDT(len); + if (len <= STM32_MDMA_MAX_BUF_LEN) { + /* Setup a buffer transfer */ + ccr |= STM32_MDMA_CCR_TCIE | STM32_MDMA_CCR_CTCIE; + ctcr |= STM32_MDMA_CTCR_TRGM(STM32_MDMA_BUFFER); + } else { + /* Setup a block transfer */ + ccr |= STM32_MDMA_CCR_BTIE | STM32_MDMA_CCR_CTCIE; + ctcr |= STM32_MDMA_CTCR_TRGM(STM32_MDMA_BLOCK); + } + + tlen = STM32_MDMA_MAX_BUF_LEN; + ctcr |= STM32_MDMA_CTCR_TLEN((tlen - 1)); + + /* Set source best burst size */ + max_width = stm32_mdma_get_max_width(src, len, tlen); + src_bus_width = stm32_mdma_get_width(chan, max_width); + + max_burst = tlen / max_width; + best_burst = stm32_mdma_get_best_burst(len, tlen, max_burst, + max_width); + mdma_burst = ilog2(best_burst); + + ctcr |= STM32_MDMA_CTCR_SBURST(mdma_burst) | + STM32_MDMA_CTCR_SSIZE(src_bus_width) | + STM32_MDMA_CTCR_SINCOS(src_bus_width); + + /* Set destination best burst size */ + max_width = stm32_mdma_get_max_width(dest, len, tlen); + dst_bus_width = stm32_mdma_get_width(chan, max_width); + + max_burst = tlen / max_width; + best_burst = stm32_mdma_get_best_burst(len, tlen, max_burst, + max_width); + mdma_burst = ilog2(best_burst); + + ctcr |= STM32_MDMA_CTCR_DBURST(mdma_burst) | + STM32_MDMA_CTCR_DSIZE(dst_bus_width) | + STM32_MDMA_CTCR_DINCOS(dst_bus_width); + + if (dst_bus_width != src_bus_width) + ctcr |= STM32_MDMA_CTCR_PKE; + + /* Prepare hardware descriptor */ + hwdesc = desc->node[0].hwdesc; + hwdesc->ctcr = ctcr; + hwdesc->cbndtr = cbndtr; + hwdesc->csar = src; + hwdesc->cdar = dest; + hwdesc->cbrur = 0; + hwdesc->clar = 0; + hwdesc->ctbr = ctbr; + hwdesc->cmar = 0; + hwdesc->cmdr = 0; + + stm32_mdma_dump_hwdesc(chan, &desc->node[0]); + } else { + /* Setup a LLI transfer */ + ctcr |= STM32_MDMA_CTCR_TRGM(STM32_MDMA_LINKED_LIST) | + STM32_MDMA_CTCR_TLEN((STM32_MDMA_MAX_BUF_LEN - 1)); + ccr |= STM32_MDMA_CCR_BTIE | STM32_MDMA_CCR_CTCIE; + tlen = STM32_MDMA_MAX_BUF_LEN; + + for (i = 0, offset = 0; offset < len; + i++, offset += xfer_count) { + xfer_count = min_t(size_t, len - offset, + STM32_MDMA_MAX_BLOCK_LEN); + + /* Set source best burst size */ + max_width = stm32_mdma_get_max_width(src, len, tlen); + src_bus_width = stm32_mdma_get_width(chan, max_width); + + max_burst = tlen / max_width; + best_burst = stm32_mdma_get_best_burst(len, tlen, + max_burst, + max_width); + mdma_burst = ilog2(best_burst); + + ctcr |= STM32_MDMA_CTCR_SBURST(mdma_burst) | + STM32_MDMA_CTCR_SSIZE(src_bus_width) | + STM32_MDMA_CTCR_SINCOS(src_bus_width); + + /* Set destination best burst size */ + max_width = stm32_mdma_get_max_width(dest, len, tlen); + dst_bus_width = stm32_mdma_get_width(chan, max_width); + + max_burst = tlen / max_width; + best_burst = stm32_mdma_get_best_burst(len, tlen, + max_burst, + max_width); + mdma_burst = ilog2(best_burst); + + ctcr |= STM32_MDMA_CTCR_DBURST(mdma_burst) | + STM32_MDMA_CTCR_DSIZE(dst_bus_width) | + STM32_MDMA_CTCR_DINCOS(dst_bus_width); + + if (dst_bus_width != src_bus_width) + ctcr |= STM32_MDMA_CTCR_PKE; + + /* Prepare hardware descriptor */ + stm32_mdma_setup_hwdesc(chan, desc, DMA_MEM_TO_MEM, i, + src + offset, dest + offset, + xfer_count, ctcr, ctbr, + i == count - 1, i == 0, false); + } + } + + desc->ccr = ccr; + + desc->cyclic = false; + + return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags); +} + +static void stm32_mdma_dump_reg(struct stm32_mdma_chan *chan) +{ + struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan); + + dev_dbg(chan2dev(chan), "CCR: 0x%08x\n", + stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id))); + dev_dbg(chan2dev(chan), "CTCR: 0x%08x\n", + stm32_mdma_read(dmadev, STM32_MDMA_CTCR(chan->id))); + dev_dbg(chan2dev(chan), "CBNDTR: 0x%08x\n", + stm32_mdma_read(dmadev, STM32_MDMA_CBNDTR(chan->id))); + dev_dbg(chan2dev(chan), "CSAR: 0x%08x\n", + stm32_mdma_read(dmadev, STM32_MDMA_CSAR(chan->id))); + dev_dbg(chan2dev(chan), "CDAR: 0x%08x\n", + stm32_mdma_read(dmadev, STM32_MDMA_CDAR(chan->id))); + dev_dbg(chan2dev(chan), "CBRUR: 0x%08x\n", + stm32_mdma_read(dmadev, STM32_MDMA_CBRUR(chan->id))); + dev_dbg(chan2dev(chan), "CLAR: 0x%08x\n", + stm32_mdma_read(dmadev, STM32_MDMA_CLAR(chan->id))); + dev_dbg(chan2dev(chan), "CTBR: 0x%08x\n", + stm32_mdma_read(dmadev, STM32_MDMA_CTBR(chan->id))); + dev_dbg(chan2dev(chan), "CMAR: 0x%08x\n", + stm32_mdma_read(dmadev, STM32_MDMA_CMAR(chan->id))); + dev_dbg(chan2dev(chan), "CMDR: 0x%08x\n", + stm32_mdma_read(dmadev, STM32_MDMA_CMDR(chan->id))); +} + +static void stm32_mdma_start_transfer(struct stm32_mdma_chan *chan) +{ + struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan); + struct virt_dma_desc *vdesc; + struct stm32_mdma_hwdesc *hwdesc; + u32 id = chan->id; + u32 status, reg; + + vdesc = vchan_next_desc(&chan->vchan); + if (!vdesc) { + chan->desc = NULL; + return; + } + + list_del(&vdesc->node); + + chan->desc = to_stm32_mdma_desc(vdesc); + hwdesc = chan->desc->node[0].hwdesc; + chan->curr_hwdesc = 0; + + stm32_mdma_write(dmadev, STM32_MDMA_CCR(id), chan->desc->ccr); + stm32_mdma_write(dmadev, STM32_MDMA_CTCR(id), hwdesc->ctcr); + stm32_mdma_write(dmadev, STM32_MDMA_CBNDTR(id), hwdesc->cbndtr); + stm32_mdma_write(dmadev, STM32_MDMA_CSAR(id), hwdesc->csar); + stm32_mdma_write(dmadev, STM32_MDMA_CDAR(id), hwdesc->cdar); + stm32_mdma_write(dmadev, STM32_MDMA_CBRUR(id), hwdesc->cbrur); + stm32_mdma_write(dmadev, STM32_MDMA_CLAR(id), hwdesc->clar); + stm32_mdma_write(dmadev, STM32_MDMA_CTBR(id), hwdesc->ctbr); + stm32_mdma_write(dmadev, STM32_MDMA_CMAR(id), hwdesc->cmar); + stm32_mdma_write(dmadev, STM32_MDMA_CMDR(id), hwdesc->cmdr); + + /* Clear interrupt status if it is there */ + status = stm32_mdma_read(dmadev, STM32_MDMA_CISR(id)); + if (status) + stm32_mdma_set_bits(dmadev, STM32_MDMA_CIFCR(id), status); + + stm32_mdma_dump_reg(chan); + + /* Start DMA */ + stm32_mdma_set_bits(dmadev, STM32_MDMA_CCR(id), STM32_MDMA_CCR_EN); + + /* Set SW request in case of MEM2MEM transfer */ + if (hwdesc->ctcr & STM32_MDMA_CTCR_SWRM) { + reg = STM32_MDMA_CCR(id); + stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CCR_SWRQ); + } + + chan->busy = true; + + dev_dbg(chan2dev(chan), "vchan %pK: started\n", &chan->vchan); +} + +static void stm32_mdma_issue_pending(struct dma_chan *c) +{ + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c); + unsigned long flags; + + spin_lock_irqsave(&chan->vchan.lock, flags); + + if (!vchan_issue_pending(&chan->vchan)) + goto end; + + dev_dbg(chan2dev(chan), "vchan %pK: issued\n", &chan->vchan); + + if (!chan->desc && !chan->busy) + stm32_mdma_start_transfer(chan); + +end: + spin_unlock_irqrestore(&chan->vchan.lock, flags); +} + +static int stm32_mdma_pause(struct dma_chan *c) +{ + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c); + unsigned long flags; + int ret; + + spin_lock_irqsave(&chan->vchan.lock, flags); + ret = stm32_mdma_disable_chan(chan); + spin_unlock_irqrestore(&chan->vchan.lock, flags); + + if (!ret) + dev_dbg(chan2dev(chan), "vchan %pK: pause\n", &chan->vchan); + + return ret; +} + +static int stm32_mdma_resume(struct dma_chan *c) +{ + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c); + struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan); + struct stm32_mdma_hwdesc *hwdesc; + unsigned long flags; + u32 status, reg; + + /* Transfer can be terminated */ + if (!chan->desc || (stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id)) & STM32_MDMA_CCR_EN)) + return -EPERM; + + hwdesc = chan->desc->node[chan->curr_hwdesc].hwdesc; + + spin_lock_irqsave(&chan->vchan.lock, flags); + + /* Re-configure control register */ + stm32_mdma_write(dmadev, STM32_MDMA_CCR(chan->id), chan->desc->ccr); + + /* Clear interrupt status if it is there */ + status = stm32_mdma_read(dmadev, STM32_MDMA_CISR(chan->id)); + if (status) + stm32_mdma_set_bits(dmadev, STM32_MDMA_CIFCR(chan->id), status); + + stm32_mdma_dump_reg(chan); + + /* Re-start DMA */ + reg = STM32_MDMA_CCR(chan->id); + stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CCR_EN); + + /* Set SW request in case of MEM2MEM transfer */ + if (hwdesc->ctcr & STM32_MDMA_CTCR_SWRM) + stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CCR_SWRQ); + + spin_unlock_irqrestore(&chan->vchan.lock, flags); + + dev_dbg(chan2dev(chan), "vchan %pK: resume\n", &chan->vchan); + + return 0; +} + +static int stm32_mdma_terminate_all(struct dma_chan *c) +{ + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c); + unsigned long flags; + LIST_HEAD(head); + + spin_lock_irqsave(&chan->vchan.lock, flags); + if (chan->desc) { + vchan_terminate_vdesc(&chan->desc->vdesc); + if (chan->busy) + stm32_mdma_stop(chan); + chan->desc = NULL; + } + vchan_get_all_descriptors(&chan->vchan, &head); + spin_unlock_irqrestore(&chan->vchan.lock, flags); + + vchan_dma_desc_free_list(&chan->vchan, &head); + + return 0; +} + +static void stm32_mdma_synchronize(struct dma_chan *c) +{ + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c); + + vchan_synchronize(&chan->vchan); +} + +static int stm32_mdma_slave_config(struct dma_chan *c, + struct dma_slave_config *config) +{ + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c); + + memcpy(&chan->dma_config, config, sizeof(*config)); + + /* Check if user is requesting STM32 DMA to trigger MDMA */ + if (config->peripheral_size) { + struct stm32_mdma_dma_config *mdma_config; + + mdma_config = (struct stm32_mdma_dma_config *)chan->dma_config.peripheral_config; + chan->chan_config.request = mdma_config->request; + chan->chan_config.mask_addr = mdma_config->cmar; + chan->chan_config.mask_data = mdma_config->cmdr; + chan->chan_config.m2m_hw = true; + } + + return 0; +} + +static size_t stm32_mdma_desc_residue(struct stm32_mdma_chan *chan, + struct stm32_mdma_desc *desc, + u32 curr_hwdesc, + struct dma_tx_state *state) +{ + struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan); + struct stm32_mdma_hwdesc *hwdesc; + u32 cisr, clar, cbndtr, residue, modulo, burst_size; + int i; + + cisr = stm32_mdma_read(dmadev, STM32_MDMA_CISR(chan->id)); + + residue = 0; + /* Get the next hw descriptor to process from current transfer */ + clar = stm32_mdma_read(dmadev, STM32_MDMA_CLAR(chan->id)); + for (i = desc->count - 1; i >= 0; i--) { + hwdesc = desc->node[i].hwdesc; + + if (hwdesc->clar == clar) + break;/* Current transfer found, stop cumulating */ + + /* Cumulate residue of unprocessed hw descriptors */ + residue += STM32_MDMA_CBNDTR_BNDT(hwdesc->cbndtr); + } + cbndtr = stm32_mdma_read(dmadev, STM32_MDMA_CBNDTR(chan->id)); + residue += cbndtr & STM32_MDMA_CBNDTR_BNDT_MASK; + + state->in_flight_bytes = 0; + if (chan->chan_config.m2m_hw && (cisr & STM32_MDMA_CISR_CRQA)) + state->in_flight_bytes = cbndtr & STM32_MDMA_CBNDTR_BNDT_MASK; + + if (!chan->mem_burst) + return residue; + + burst_size = chan->mem_burst * chan->mem_width; + modulo = residue % burst_size; + if (modulo) + residue = residue - modulo + burst_size; + + return residue; +} + +static enum dma_status stm32_mdma_tx_status(struct dma_chan *c, + dma_cookie_t cookie, + struct dma_tx_state *state) +{ + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c); + struct virt_dma_desc *vdesc; + enum dma_status status; + unsigned long flags; + u32 residue = 0; + + status = dma_cookie_status(c, cookie, state); + if ((status == DMA_COMPLETE) || (!state)) + return status; + + spin_lock_irqsave(&chan->vchan.lock, flags); + + vdesc = vchan_find_desc(&chan->vchan, cookie); + if (chan->desc && cookie == chan->desc->vdesc.tx.cookie) + residue = stm32_mdma_desc_residue(chan, chan->desc, chan->curr_hwdesc, state); + else if (vdesc) + residue = stm32_mdma_desc_residue(chan, to_stm32_mdma_desc(vdesc), 0, state); + + dma_set_residue(state, residue); + + spin_unlock_irqrestore(&chan->vchan.lock, flags); + + return status; +} + +static void stm32_mdma_xfer_end(struct stm32_mdma_chan *chan) +{ + vchan_cookie_complete(&chan->desc->vdesc); + chan->desc = NULL; + chan->busy = false; + + /* Start the next transfer if this driver has a next desc */ + stm32_mdma_start_transfer(chan); +} + +static irqreturn_t stm32_mdma_irq_handler(int irq, void *devid) +{ + struct stm32_mdma_device *dmadev = devid; + struct stm32_mdma_chan *chan; + u32 reg, id, ccr, ien, status; + + /* Find out which channel generates the interrupt */ + status = readl_relaxed(dmadev->base + STM32_MDMA_GISR0); + if (!status) { + dev_dbg(mdma2dev(dmadev), "spurious it\n"); + return IRQ_NONE; + } + id = __ffs(status); + chan = &dmadev->chan[id]; + + /* Handle interrupt for the channel */ + spin_lock(&chan->vchan.lock); + status = stm32_mdma_read(dmadev, STM32_MDMA_CISR(id)); + /* Mask Channel ReQuest Active bit which can be set in case of MEM2MEM */ + status &= ~STM32_MDMA_CISR_CRQA; + ccr = stm32_mdma_read(dmadev, STM32_MDMA_CCR(id)); + ien = (ccr & STM32_MDMA_CCR_IRQ_MASK) >> 1; + + if (!(status & ien)) { + spin_unlock(&chan->vchan.lock); + if (chan->busy) + dev_warn(chan2dev(chan), + "spurious it (status=0x%04x, ien=0x%04x)\n", status, ien); + else + dev_dbg(chan2dev(chan), + "spurious it (status=0x%04x, ien=0x%04x)\n", status, ien); + return IRQ_NONE; + } + + reg = STM32_MDMA_CIFCR(id); + + if (status & STM32_MDMA_CISR_TEIF) { + dev_err(chan2dev(chan), "Transfer Err: stat=0x%08x\n", + readl_relaxed(dmadev->base + STM32_MDMA_CESR(id))); + stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CTEIF); + status &= ~STM32_MDMA_CISR_TEIF; + } + + if (status & STM32_MDMA_CISR_CTCIF) { + stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CCTCIF); + status &= ~STM32_MDMA_CISR_CTCIF; + stm32_mdma_xfer_end(chan); + } + + if (status & STM32_MDMA_CISR_BRTIF) { + stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CBRTIF); + status &= ~STM32_MDMA_CISR_BRTIF; + } + + if (status & STM32_MDMA_CISR_BTIF) { + stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CBTIF); + status &= ~STM32_MDMA_CISR_BTIF; + chan->curr_hwdesc++; + if (chan->desc && chan->desc->cyclic) { + if (chan->curr_hwdesc == chan->desc->count) + chan->curr_hwdesc = 0; + vchan_cyclic_callback(&chan->desc->vdesc); + } + } + + if (status & STM32_MDMA_CISR_TCIF) { + stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CLTCIF); + status &= ~STM32_MDMA_CISR_TCIF; + } + + if (status) { + stm32_mdma_set_bits(dmadev, reg, status); + dev_err(chan2dev(chan), "DMA error: status=0x%08x\n", status); + if (!(ccr & STM32_MDMA_CCR_EN)) + dev_err(chan2dev(chan), "chan disabled by HW\n"); + } + + spin_unlock(&chan->vchan.lock); + + return IRQ_HANDLED; +} + +static int stm32_mdma_alloc_chan_resources(struct dma_chan *c) +{ + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c); + struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan); + int ret; + + chan->desc_pool = dmam_pool_create(dev_name(&c->dev->device), + c->device->dev, + sizeof(struct stm32_mdma_hwdesc), + __alignof__(struct stm32_mdma_hwdesc), + 0); + if (!chan->desc_pool) { + dev_err(chan2dev(chan), "failed to allocate descriptor pool\n"); + return -ENOMEM; + } + + ret = pm_runtime_resume_and_get(dmadev->ddev.dev); + if (ret < 0) + return ret; + + ret = stm32_mdma_disable_chan(chan); + if (ret < 0) + pm_runtime_put(dmadev->ddev.dev); + + return ret; +} + +static void stm32_mdma_free_chan_resources(struct dma_chan *c) +{ + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c); + struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan); + unsigned long flags; + + dev_dbg(chan2dev(chan), "Freeing channel %d\n", chan->id); + + if (chan->busy) { + spin_lock_irqsave(&chan->vchan.lock, flags); + stm32_mdma_stop(chan); + chan->desc = NULL; + spin_unlock_irqrestore(&chan->vchan.lock, flags); + } + + pm_runtime_put(dmadev->ddev.dev); + vchan_free_chan_resources(to_virt_chan(c)); + dmam_pool_destroy(chan->desc_pool); + chan->desc_pool = NULL; +} + +static bool stm32_mdma_filter_fn(struct dma_chan *c, void *fn_param) +{ + struct stm32_mdma_chan *chan = to_stm32_mdma_chan(c); + struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan); + + /* Check if chan is marked Secure */ + if (dmadev->chan_reserved & BIT(chan->id)) + return false; + + return true; +} + +static struct dma_chan *stm32_mdma_of_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct stm32_mdma_device *dmadev = ofdma->of_dma_data; + dma_cap_mask_t mask = dmadev->ddev.cap_mask; + struct stm32_mdma_chan *chan; + struct dma_chan *c; + struct stm32_mdma_chan_config config; + + if (dma_spec->args_count < 5) { + dev_err(mdma2dev(dmadev), "Bad number of args\n"); + return NULL; + } + + memset(&config, 0, sizeof(config)); + config.request = dma_spec->args[0]; + config.priority_level = dma_spec->args[1]; + config.transfer_config = dma_spec->args[2]; + config.mask_addr = dma_spec->args[3]; + config.mask_data = dma_spec->args[4]; + + if (config.request >= dmadev->nr_requests) { + dev_err(mdma2dev(dmadev), "Bad request line\n"); + return NULL; + } + + if (config.priority_level > STM32_MDMA_VERY_HIGH_PRIORITY) { + dev_err(mdma2dev(dmadev), "Priority level not supported\n"); + return NULL; + } + + c = __dma_request_channel(&mask, stm32_mdma_filter_fn, &config, ofdma->of_node); + if (!c) { + dev_err(mdma2dev(dmadev), "No more channels available\n"); + return NULL; + } + + chan = to_stm32_mdma_chan(c); + chan->chan_config = config; + + return c; +} + +static const struct of_device_id stm32_mdma_of_match[] = { + { .compatible = "st,stm32h7-mdma", }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, stm32_mdma_of_match); + +static int stm32_mdma_probe(struct platform_device *pdev) +{ + struct stm32_mdma_chan *chan; + struct stm32_mdma_device *dmadev; + struct dma_device *dd; + struct device_node *of_node; + struct resource *res; + struct reset_control *rst; + u32 nr_channels, nr_requests; + int i, count, ret; + + of_node = pdev->dev.of_node; + if (!of_node) + return -ENODEV; + + ret = device_property_read_u32(&pdev->dev, "dma-channels", + &nr_channels); + if (ret) { + nr_channels = STM32_MDMA_MAX_CHANNELS; + dev_warn(&pdev->dev, "MDMA defaulting on %i channels\n", + nr_channels); + } + + ret = device_property_read_u32(&pdev->dev, "dma-requests", + &nr_requests); + if (ret) { + nr_requests = STM32_MDMA_MAX_REQUESTS; + dev_warn(&pdev->dev, "MDMA defaulting on %i request lines\n", + nr_requests); + } + + count = device_property_count_u32(&pdev->dev, "st,ahb-addr-masks"); + if (count < 0) + count = 0; + + dmadev = devm_kzalloc(&pdev->dev, + struct_size(dmadev, ahb_addr_masks, count), + GFP_KERNEL); + if (!dmadev) + return -ENOMEM; + + dmadev->nr_channels = nr_channels; + dmadev->nr_requests = nr_requests; + device_property_read_u32_array(&pdev->dev, "st,ahb-addr-masks", + dmadev->ahb_addr_masks, + count); + dmadev->nr_ahb_addr_masks = count; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + dmadev->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(dmadev->base)) + return PTR_ERR(dmadev->base); + + dmadev->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(dmadev->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(dmadev->clk), + "Missing clock controller\n"); + + ret = clk_prepare_enable(dmadev->clk); + if (ret < 0) { + dev_err(&pdev->dev, "clk_prep_enable error: %d\n", ret); + return ret; + } + + rst = devm_reset_control_get(&pdev->dev, NULL); + if (IS_ERR(rst)) { + ret = PTR_ERR(rst); + if (ret == -EPROBE_DEFER) + goto err_clk; + } else { + reset_control_assert(rst); + udelay(2); + reset_control_deassert(rst); + } + + dd = &dmadev->ddev; + dma_cap_set(DMA_SLAVE, dd->cap_mask); + dma_cap_set(DMA_PRIVATE, dd->cap_mask); + dma_cap_set(DMA_CYCLIC, dd->cap_mask); + dma_cap_set(DMA_MEMCPY, dd->cap_mask); + dd->device_alloc_chan_resources = stm32_mdma_alloc_chan_resources; + dd->device_free_chan_resources = stm32_mdma_free_chan_resources; + dd->device_tx_status = stm32_mdma_tx_status; + dd->device_issue_pending = stm32_mdma_issue_pending; + dd->device_prep_slave_sg = stm32_mdma_prep_slave_sg; + dd->device_prep_dma_cyclic = stm32_mdma_prep_dma_cyclic; + dd->device_prep_dma_memcpy = stm32_mdma_prep_dma_memcpy; + dd->device_config = stm32_mdma_slave_config; + dd->device_pause = stm32_mdma_pause; + dd->device_resume = stm32_mdma_resume; + dd->device_terminate_all = stm32_mdma_terminate_all; + dd->device_synchronize = stm32_mdma_synchronize; + dd->descriptor_reuse = true; + + dd->src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | + BIT(DMA_SLAVE_BUSWIDTH_8_BYTES); + dd->dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | + BIT(DMA_SLAVE_BUSWIDTH_8_BYTES); + dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV) | + BIT(DMA_MEM_TO_MEM); + dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; + dd->max_burst = STM32_MDMA_MAX_BURST; + dd->dev = &pdev->dev; + INIT_LIST_HEAD(&dd->channels); + + for (i = 0; i < dmadev->nr_channels; i++) { + chan = &dmadev->chan[i]; + chan->id = i; + + if (stm32_mdma_read(dmadev, STM32_MDMA_CCR(i)) & STM32_MDMA_CCR_SM) + dmadev->chan_reserved |= BIT(i); + + chan->vchan.desc_free = stm32_mdma_desc_free; + vchan_init(&chan->vchan, dd); + } + + dmadev->irq = platform_get_irq(pdev, 0); + if (dmadev->irq < 0) { + ret = dmadev->irq; + goto err_clk; + } + + ret = devm_request_irq(&pdev->dev, dmadev->irq, stm32_mdma_irq_handler, + 0, dev_name(&pdev->dev), dmadev); + if (ret) { + dev_err(&pdev->dev, "failed to request IRQ\n"); + goto err_clk; + } + + ret = dmaenginem_async_device_register(dd); + if (ret) + goto err_clk; + + ret = of_dma_controller_register(of_node, stm32_mdma_of_xlate, dmadev); + if (ret < 0) { + dev_err(&pdev->dev, + "STM32 MDMA DMA OF registration failed %d\n", ret); + goto err_clk; + } + + platform_set_drvdata(pdev, dmadev); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + pm_runtime_get_noresume(&pdev->dev); + pm_runtime_put(&pdev->dev); + + dev_info(&pdev->dev, "STM32 MDMA driver registered\n"); + + return 0; + +err_clk: + clk_disable_unprepare(dmadev->clk); + + return ret; +} + +#ifdef CONFIG_PM +static int stm32_mdma_runtime_suspend(struct device *dev) +{ + struct stm32_mdma_device *dmadev = dev_get_drvdata(dev); + + clk_disable_unprepare(dmadev->clk); + + return 0; +} + +static int stm32_mdma_runtime_resume(struct device *dev) +{ + struct stm32_mdma_device *dmadev = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(dmadev->clk); + if (ret) { + dev_err(dev, "failed to prepare_enable clock\n"); + return ret; + } + + return 0; +} +#endif + +#ifdef CONFIG_PM_SLEEP +static int stm32_mdma_pm_suspend(struct device *dev) +{ + struct stm32_mdma_device *dmadev = dev_get_drvdata(dev); + u32 ccr, id; + int ret; + + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) + return ret; + + for (id = 0; id < dmadev->nr_channels; id++) { + ccr = stm32_mdma_read(dmadev, STM32_MDMA_CCR(id)); + if (ccr & STM32_MDMA_CCR_EN) { + dev_warn(dev, "Suspend is prevented by Chan %i\n", id); + return -EBUSY; + } + } + + pm_runtime_put_sync(dev); + + pm_runtime_force_suspend(dev); + + return 0; +} + +static int stm32_mdma_pm_resume(struct device *dev) +{ + return pm_runtime_force_resume(dev); +} +#endif + +static const struct dev_pm_ops stm32_mdma_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(stm32_mdma_pm_suspend, stm32_mdma_pm_resume) + SET_RUNTIME_PM_OPS(stm32_mdma_runtime_suspend, + stm32_mdma_runtime_resume, NULL) +}; + +static struct platform_driver stm32_mdma_driver = { + .probe = stm32_mdma_probe, + .driver = { + .name = "stm32-mdma", + .of_match_table = stm32_mdma_of_match, + .pm = &stm32_mdma_pm_ops, + }, +}; + +static int __init stm32_mdma_init(void) +{ + return platform_driver_register(&stm32_mdma_driver); +} + +subsys_initcall(stm32_mdma_init); + +MODULE_DESCRIPTION("Driver for STM32 MDMA controller"); +MODULE_AUTHOR("M'boumba Cedric Madianga <cedric.madianga@gmail.com>"); +MODULE_AUTHOR("Pierre-Yves Mordret <pierre-yves.mordret@st.com>"); +MODULE_LICENSE("GPL v2"); |