[PATCH 2/2] dmaengine: Add STM32 MDMA driver
M'boumba Cedric Madianga
cedric.madianga at gmail.com
Mon Mar 13 08:06:39 PDT 2017
This patch adds the driver for the STM32 MDMA controller.
Signed-off-by: M'boumba Cedric Madianga <cedric.madianga at gmail.com>
Reviewed-by: Ludovic BARRE <ludovic.barre at st.com>
---
drivers/dma/Kconfig | 12 +
drivers/dma/Makefile | 1 +
drivers/dma/stm32-mdma.c | 1570 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 1583 insertions(+)
create mode 100644 drivers/dma/stm32-mdma.c
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 6ab80c9..beae8b0 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -470,6 +470,18 @@ config STM32_DMAMUX
If you have a board based on such a MCU and wish to use DMAMUX say Y
here.
+config STM32_MDMA
+ bool "STMicroelectronics STM32 master dma support"
+ depends on ARCH_STM32 || COMPILE_TEST
+ select DMA_ENGINE
+ select DMA_OF
+ select DMA_VIRTUAL_CHANNELS
+ help
+ Enable support for the on-chip MDMA controller on STMicroelectronics
+ STM32 platforms.
+ If you have a board based on STM32 SoC and wish to use the master DMA
+ say Y here.
+
config S3C24XX_DMAC
bool "Samsung S3C24XX DMA support"
depends on ARCH_S3C24XX || COMPILE_TEST
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index 449c7a3..003b515 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -58,6 +58,7 @@ obj-$(CONFIG_SIRF_DMA) += sirf-dma.o
obj-$(CONFIG_STE_DMA40) += ste_dma40.o ste_dma40_ll.o
obj-$(CONFIG_STM32_DMA) += stm32-dma.o
obj-$(CONFIG_STM32_DMAMUX) += stm32-dmamux.o
+obj-$(CONFIG_STM32_MDMA) += stm32-mdma.o
obj-$(CONFIG_S3C24XX_DMAC) += s3c24xx-dma.o
obj-$(CONFIG_TXX9_DMAC) += txx9dmac.o
obj-$(CONFIG_TEGRA20_APB_DMA) += tegra20-apb-dma.o
diff --git a/drivers/dma/stm32-mdma.c b/drivers/dma/stm32-mdma.c
new file mode 100644
index 0000000..23d267c
--- /dev/null
+++ b/drivers/dma/stm32-mdma.c
@@ -0,0 +1,1570 @@
+/*
+ * Driver for STM32 MDMA controller
+ *
+ * Inspired by stm32-dma.c and dma-jz4780.c
+ *
+ * Copyright (C) M'boumba Cedric Madianga 2017
+ * Author: M'boumba Cedric Madianga <cedric.madianga at gmail.com>
+ *
+ * License terms: GNU General Public License (GPL), version 2
+ */
+
+#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/reset.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+
+#include "virt-dma.h"
+
+#define STM32_MDMA_GISR0 0x0000 /* MDMA Int Status Reg 1 */
+#define STM32_MDMA_GISR1 0x0004 /* MDMA Int Status Reg 2 */
+
+/* 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_PL_MASK GENMASK(7, 6)
+#define STM32_MDMA_CCR_PL(n) (((n) & 0x3) << 6)
+#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) (((n) & 0x3) << 28)
+#define STM32_MDMA_CTCR_TRGM_GET(n) (((n) & STM32_MDMA_CTCR_TRGM_MSK) >> 28)
+#define STM32_MDMA_CTCR_PAM_MASK GENMASK(27, 26)
+#define STM32_MDMA_CTCR_PAM(n) (((n) & 0x3) << 26)
+#define STM32_MDMA_CTCR_PKE BIT(25)
+#define STM32_MDMA_CTCR_TLEN_MSK GENMASK(24, 18)
+#define STM32_MDMA_CTCR_TLEN(n) (((n) & 0x7f) << 18)
+#define STM32_MDMA_CTCR_TLEN_GET(n) (((n) & STM32_MDMA_CTCR_TLEN_MSK) >> 18)
+#define STM32_MDMA_CTCR_LEN2_MSK GENMASK(25, 18)
+#define STM32_MDMA_CTCR_LEN2(n) (((n) & 0xff) << 18)
+#define STM32_MDMA_CTCR_LEN2_GET(n) (((n) & STM32_MDMA_CTCR_LEN2_MSK) >> 18)
+#define STM32_MDMA_CTCR_DBURST_MASK GENMASK(17, 15)
+#define STM32_MDMA_CTCR_DBURST(n) (((n) & 0x7) << 15)
+#define STM32_MDMA_CTCR_SBURST_MASK GENMASK(14, 12)
+#define STM32_MDMA_CTCR_SBURST(n) (((n) & 0x7) << 12)
+#define STM32_MDMA_CTCR_DINCOS_MASK GENMASK(11, 10)
+#define STM32_MDMA_CTCR_DINCOS(n) (((n) & 0x3) << 10)
+#define STM32_MDMA_CTCR_SINCOS_MASK GENMASK(9, 8)
+#define STM32_MDMA_CTCR_SINCOS(n) (((n) & 0x3) << 8)
+#define STM32_MDMA_CTCR_DSIZE_MASK GENMASK(7, 6)
+#define STM32_MDMA_CTCR_DSIZE(n) (((n) & 0x3) << 6)
+#define STM32_MDMA_CTCR_SSIZE_MASK GENMASK(5, 4)
+#define STM32_MDMA_CTCR_SSIZE(n) (((n) & 0x3) << 4)
+#define STM32_MDMA_CTCR_DINC_MASK GENMASK(3, 2)
+#define STM32_MDMA_CTCR_DINC(n) (((n) & 0x3) << 2)
+#define STM32_MDMA_CTCR_SINC_MASK GENMASK(1, 0)
+#define STM32_MDMA_CTCR_SINC(n) ((n) & STM32_MDMA_CTCR_SINC_MASK)
+#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) (((n) & 0xfff) << 20)
+#define STM32_MDMA_CBNDTR_BRC_GET(n) (((n) & STM32_MDMA_CBNDTR_BRC_MK) >> 20)
+#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) ((n) & STM32_MDMA_CBNDTR_BNDT_MASK)
+
+/* 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) (((n) & 0xffff) << 16)
+#define STM32_MDMA_CBRUR_SUV_MASK GENMASK(15, 0)
+#define STM32_MDMA_CBRUR_SUV(n) ((n) & STM32_MDMA_CBRUR_SUV_MASK)
+
+/* 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(7, 0)
+#define STM32_MDMA_CTBR_TSEL(n) ((n) & STM32_MDMA_CTBR_TSEL_MASK)
+
+/* 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 63
+#define STM32_MDMA_MAX_REQUESTS 256
+#define STM32_MDMA_MAX_BURST 128
+#define STM32_MDMA_VERY_HIGH_PRIORITY 0x11
+
+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;
+};
+
+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 {
+ struct virt_dma_desc vdesc;
+ u32 ccr;
+ struct stm32_mdma_hwdesc *hwdesc;
+ dma_addr_t hwdesc_phys;
+ bool cyclic;
+ u32 count;
+};
+
+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;
+ u32 irq;
+ struct reset_control *rst;
+ u32 nr_channels;
+ u32 nr_requests;
+ u32 nr_ahb_addr_masks;
+ 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;
+
+ desc = kzalloc(sizeof(*desc), GFP_NOWAIT);
+ if (!desc)
+ return NULL;
+
+ desc->hwdesc = dma_pool_alloc(chan->desc_pool, GFP_NOWAIT,
+ &desc->hwdesc_phys);
+ if (!desc->hwdesc) {
+ dev_err(chan2dev(chan), "Failed to allocate descriptor\n");
+ kfree(desc);
+ return NULL;
+ }
+
+ desc->count = count;
+
+ return desc;
+}
+
+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);
+
+ dma_pool_free(chan->desc_pool, desc->hwdesc, desc->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:
+ return STM32_MDMA_BYTE;
+ case DMA_SLAVE_BUSWIDTH_2_BYTES:
+ return STM32_MDMA_HALF_WORD;
+ case DMA_SLAVE_BUSWIDTH_4_BYTES:
+ return STM32_MDMA_WORD;
+ case DMA_SLAVE_BUSWIDTH_8_BYTES:
+ return STM32_MDMA_DOUBLE_WORD;
+ default:
+ dev_err(chan2dev(chan), "Dma bus width not supported\n");
+ return -EINVAL;
+ }
+}
+
+static enum dma_slave_buswidth stm32_mdma_get_max_width(u32 buf_len, u32 tlen)
+{
+ enum dma_slave_buswidth max_width = DMA_SLAVE_BUSWIDTH_8_BYTES;
+
+ while ((buf_len <= max_width || buf_len % max_width ||
+ tlen < max_width) && max_width > DMA_SLAVE_BUSWIDTH_1_BYTE)
+ max_width = max_width >> 1;
+
+ 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 = max_burst;
+ u32 burst_len = best_burst * width;
+
+ if (buf_len % tlen)
+ return 0;
+
+ while ((tlen < burst_len && best_burst > 1) ||
+ (burst_len > 0 && tlen % burst_len)) {
+ best_burst = best_burst >> 1;
+ burst_len = best_burst * width;
+ }
+
+ return (best_burst > 1) ? best_burst : 0;
+}
+
+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_dst_bus(struct stm32_mdma_device *dmadev, u32 *ctbr,
+ u32 dst_addr)
+{
+ u32 mask;
+ int i;
+
+ /* Check if memory device is on AHB or AXI */
+ *ctbr &= ~STM32_MDMA_CTBR_DBUS;
+ mask = dst_addr & 0xF0000000;
+ for (i = 0; i < dmadev->nr_ahb_addr_masks; i++) {
+ if (mask == dmadev->ahb_addr_masks[i]) {
+ *ctbr |= STM32_MDMA_CTBR_DBUS;
+ break;
+ }
+ }
+}
+
+static void stm32_mdma_set_src_bus(struct stm32_mdma_device *dmadev, u32 *ctbr,
+ u32 src_addr)
+{
+ u32 mask;
+ int i;
+
+ /* Check if memory device is on AHB or AXI */
+ *ctbr &= ~STM32_MDMA_CTBR_SBUS;
+ mask = src_addr & 0xF0000000;
+ for (i = 0; i < dmadev->nr_ahb_addr_masks; i++) {
+ if (mask == dmadev->ahb_addr_masks[i]) {
+ *ctbr |= STM32_MDMA_CTBR_SBUS;
+ 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, 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;
+ src_addr = chan->dma_config.src_addr;
+ dst_addr = chan->dma_config.dst_addr;
+
+ ccr = stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id));
+ 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));
+
+ /* 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:
+ /* Set device data size */
+ 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);
+
+ /* Set device burst value */
+ 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;
+ if (!dst_best_burst)
+ ctcr |= STM32_MDMA_CTCR_DBURST(dst_best_burst);
+ else
+ ctcr |= STM32_MDMA_CTCR_DBURST((ilog2(dst_best_burst)));
+
+ /* Set memory data size */
+ src_addr_width = stm32_mdma_get_max_width(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;
+ if (!src_best_burst)
+ ctcr |= STM32_MDMA_CTCR_SBURST(src_best_burst);
+ else
+ ctcr |= STM32_MDMA_CTCR_SBURST((ilog2(src_best_burst)));
+
+ /* Select bus */
+ stm32_mdma_set_dst_bus(dmadev, &ctbr, dst_addr);
+
+ /* Set destination address */
+ stm32_mdma_write(dmadev, STM32_MDMA_CDAR(chan->id), dst_addr);
+ break;
+
+ case DMA_DEV_TO_MEM:
+ /* Set device data size */
+ 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);
+
+ /* Set device burst value */
+ src_best_burst = stm32_mdma_get_best_burst(buf_len, tlen,
+ src_maxburst,
+ src_addr_width);
+ ctcr &= ~STM32_MDMA_CTCR_SBURST_MASK;
+ if (!src_best_burst)
+ ctcr |= STM32_MDMA_CTCR_SBURST(src_best_burst);
+ else
+ ctcr |= STM32_MDMA_CTCR_SBURST((ilog2(src_best_burst)));
+
+ /* Set memory data size */
+ dst_addr_width = stm32_mdma_get_max_width(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;
+ if (!dst_best_burst)
+ ctcr |= STM32_MDMA_CTCR_DBURST(dst_best_burst);
+ else
+ ctcr |= STM32_MDMA_CTCR_DBURST((ilog2(dst_best_burst)));
+
+ /* Select bus */
+ stm32_mdma_set_src_bus(dmadev, &ctbr, src_addr);
+
+ /* 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_hwdesc *hwdesc)
+{
+ dev_dbg(chan2dev(chan), "hwdesc: 0x%08x\n", (unsigned int)hwdesc);
+ dev_dbg(chan2dev(chan), "CTCR: 0x%08x\n", hwdesc->ctcr);
+ dev_dbg(chan2dev(chan), "CBNDTR: 0x%08x\n", hwdesc->cbndtr);
+ dev_dbg(chan2dev(chan), "CSAR: 0x%08x\n", hwdesc->csar);
+ dev_dbg(chan2dev(chan), "CDAR: 0x%08x\n", hwdesc->cdar);
+ dev_dbg(chan2dev(chan), "CBRUR: 0x%08x\n", hwdesc->cbrur);
+ dev_dbg(chan2dev(chan), "CLAR: 0x%08x\n", hwdesc->clar);
+ dev_dbg(chan2dev(chan), "CTBR: 0x%08x\n", hwdesc->ctbr);
+ dev_dbg(chan2dev(chan), "CMAR: 0x%08x\n", hwdesc->cmar);
+ dev_dbg(chan2dev(chan), "CMDR: 0x%08x\n\n", 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->hwdesc[count];
+ 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->clar = desc->hwdesc_phys + next * sizeof(*hwdesc);
+ hwdesc->ctbr = ctbr;
+ hwdesc->cmar = config->mask_addr;
+ hwdesc->cmdr = config->mask_data;
+
+ if (is_last) {
+ if (is_cyclic)
+ hwdesc->clar = desc->hwdesc_phys;
+ else
+ hwdesc->clar = 0;
+ }
+
+ stm32_mdma_dump_hwdesc(chan, hwdesc);
+}
+
+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 scatterlist *sg;
+ dma_addr_t src_addr, dst_addr;
+ u32 ccr, ctcr, ctbr;
+ int i, ret = 0;
+
+ 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;
+ }
+
+ ret = stm32_mdma_set_xfer_param(chan, direction, &ccr, &ctcr,
+ &ctbr, sg_dma_len(sg));
+ if (ret < 0)
+ return ret;
+
+ if (direction == DMA_MEM_TO_DEV) {
+ src_addr = sg_dma_address(sg);
+ dst_addr = dma_config->dst_addr;
+ stm32_mdma_set_src_bus(dmadev, &ctbr, src_addr);
+ } else {
+ src_addr = dma_config->src_addr;
+ dst_addr = sg_dma_address(sg);
+ stm32_mdma_set_dst_bus(dmadev, &ctbr, dst_addr);
+ }
+
+ 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;
+ if (sg_len > 1)
+ ccr |= STM32_MDMA_CCR_BTIE;
+ 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_desc *desc;
+ int ret;
+
+ 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;
+
+ desc->cyclic = false;
+
+ return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
+
+xfer_setup_err:
+ dma_pool_free(chan->desc_pool, &desc->hwdesc, desc->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_desc *desc;
+ dma_addr_t src_addr, dst_addr;
+ u32 ccr, ctcr, ctbr, count;
+ int i, ret;
+
+ 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;
+ }
+
+ /*
+ * We allow to take more number of requests till DMA is
+ * not started. The driver will loop over all requests.
+ * Once DMA is started then new requests can be queued only after
+ * terminating the DMA.
+ */
+ if (chan->busy) {
+ dev_err(chan2dev(chan), "Request not allowed when dma busy\n");
+ return NULL;
+ }
+
+ count = buf_len / period_len;
+
+ desc = stm32_mdma_alloc_desc(chan, count);
+ if (!desc)
+ return NULL;
+
+ ret = stm32_mdma_set_xfer_param(chan, direction, &ccr, &ctcr, &ctbr,
+ period_len);
+ 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;
+
+ /* Select bus */
+ if (direction == DMA_MEM_TO_DEV) {
+ src_addr = buf_addr;
+ stm32_mdma_set_src_bus(dmadev, &ctbr, src_addr);
+ } else {
+ dst_addr = buf_addr;
+ stm32_mdma_set_dst_bus(dmadev, &ctbr, dst_addr);
+ }
+
+ /* 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;
+ } else {
+ src_addr = dma_config->src_addr;
+ 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:
+ dma_pool_free(chan->desc_pool, &desc->hwdesc, desc->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 i;
+
+ 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));
+ 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_src_bus(dmadev, &ctbr, src);
+ stm32_mdma_set_dst_bus(dmadev, &ctbr, 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 */
+ tlen = len - 1;
+ ccr |= STM32_MDMA_CCR_TCIE | STM32_MDMA_CCR_CTCIE;
+ ctcr |= STM32_MDMA_CTCR_TRGM(STM32_MDMA_BUFFER);
+ ctcr |= STM32_MDMA_CTCR_TLEN((tlen));
+ } else {
+ /* Setup a block transfer */
+ tlen = STM32_MDMA_MAX_BUF_LEN - 1;
+ ccr |= STM32_MDMA_CCR_BTIE | STM32_MDMA_CCR_CTCIE;
+ ctcr |= STM32_MDMA_CTCR_TRGM(STM32_MDMA_BLOCK);
+ ctcr |= STM32_MDMA_CTCR_TLEN(tlen);
+ }
+
+ /* Set best burst size */
+ max_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ max_burst = (tlen + 1) / max_width;
+ best_burst = stm32_mdma_get_best_burst(len, tlen, max_burst,
+ max_width);
+ if (!best_burst)
+ mdma_burst = best_burst;
+ else
+ mdma_burst = ilog2(best_burst);
+
+ ctcr |= STM32_MDMA_CTCR_DBURST(mdma_burst) |
+ STM32_MDMA_CTCR_SBURST(mdma_burst);
+
+ /* Prepare hardware descriptor */
+ hwdesc = desc->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, hwdesc);
+ } 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;
+
+ 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 best burst size */
+ max_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ max_burst = STM32_MDMA_MAX_BUF_LEN / max_width;
+ best_burst = stm32_mdma_get_best_burst(xfer_count, tlen,
+ max_burst,
+ max_width);
+ if (!best_burst)
+ mdma_burst = best_burst;
+ else
+ mdma_burst = ilog2(best_burst);
+
+ ctcr &= ~(STM32_MDMA_CTCR_DBURST_MASK |
+ STM32_MDMA_CTCR_SBURST_MASK);
+ ctcr |= STM32_MDMA_CTCR_DBURST(mdma_burst) |
+ STM32_MDMA_CTCR_SBURST(mdma_burst);
+
+ /* 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;
+ }
+
+ chan->desc = to_stm32_mdma_desc(vdesc);
+ hwdesc = chan->desc->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 %p: 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 %p: 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 %p: 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;
+
+ hwdesc = &chan->desc->hwdesc[chan->curr_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 %p: 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->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));
+
+ return 0;
+}
+
+static size_t stm32_mdma_desc_residue(struct stm32_mdma_chan *chan,
+ struct stm32_mdma_desc *desc,
+ u32 curr_hwdesc)
+{
+ struct stm32_mdma_device *dmadev = stm32_mdma_get_dev(chan);
+ struct stm32_mdma_hwdesc *hwdesc = desc->hwdesc;
+ u32 cbndtr, residue, modulo, burst_size;
+ int i;
+
+ residue = 0;
+ for (i = curr_hwdesc + 1; i < desc->count; i++) {
+ hwdesc = &desc->hwdesc[i];
+ residue += STM32_MDMA_CBNDTR_BNDT(hwdesc->cbndtr);
+ }
+ cbndtr = stm32_mdma_read(dmadev, STM32_MDMA_CBNDTR(chan->id));
+ residue += 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);
+ else if (vdesc)
+ residue = stm32_mdma_desc_residue(chan,
+ to_stm32_mdma_desc(vdesc), 0);
+ 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)
+{
+ list_del(&chan->desc->vdesc.node);
+ 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 = devid;
+ u32 reg, id, ien, status, flag;
+
+ /* Find out which channel generates the interrupt */
+ status = readl_relaxed(dmadev->base + STM32_MDMA_GISR0);
+ if (status) {
+ id = __ffs(status);
+ } else {
+ status = readl_relaxed(dmadev->base + STM32_MDMA_GISR1);
+ if (!status) {
+ dev_dbg(mdma2dev(dmadev), "spurious it\n");
+ return IRQ_NONE;
+ }
+ id = __ffs(status);
+ /*
+ * As GISR0 provides status for channel id from 0 to 31,
+ * so GISR1 provides status for channel id from 32 to 62
+ */
+ id += 32;
+ }
+
+ chan = &dmadev->chan[id];
+ if (!chan) {
+ dev_err(chan2dev(chan), "MDMA channel not initialized\n");
+ goto exit;
+ }
+
+ /* Handle interrupt for the channel */
+ spin_lock(&chan->vchan.lock);
+ status = stm32_mdma_read(dmadev, STM32_MDMA_CISR(chan->id));
+ ien = stm32_mdma_read(dmadev, STM32_MDMA_CCR(chan->id));
+ ien &= STM32_MDMA_CCR_IRQ_MASK;
+ ien >>= 1;
+
+ if (!(status & ien)) {
+ dev_dbg(chan2dev(chan),
+ "spurious it (status=0x%04x, ien=0x%04x)\n",
+ status, ien);
+ return IRQ_NONE;
+ }
+
+ flag = __ffs(status & ien);
+ reg = STM32_MDMA_CIFCR(chan->id);
+
+ switch (1 << flag) {
+ case STM32_MDMA_CISR_TEIF:
+ id = chan->id;
+ status = readl_relaxed(dmadev->base + STM32_MDMA_CESR(id));
+ dev_err(chan2dev(chan), "Transfer Err: stat=0x%08x\n", status);
+ stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CTEIF);
+ break;
+
+ case STM32_MDMA_CISR_CTCIF:
+ stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CCTCIF);
+ stm32_mdma_xfer_end(chan);
+ break;
+
+ case STM32_MDMA_CISR_BRTIF:
+ stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CBRTIF);
+ break;
+
+ case STM32_MDMA_CISR_BTIF:
+ stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CBTIF);
+ 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);
+ }
+ break;
+
+ case STM32_MDMA_CISR_TCIF:
+ stm32_mdma_set_bits(dmadev, reg, STM32_MDMA_CIFCR_CLTCIF);
+ break;
+
+ default:
+ dev_err(chan2dev(chan), "it %d unhandled (status=0x%04x)\n",
+ 1 << flag, status);
+ }
+
+ spin_unlock(&chan->vchan.lock);
+
+exit:
+ 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 = clk_prepare_enable(dmadev->clk);
+ if (ret < 0) {
+ dev_err(chan2dev(chan), "clk_prepare_enable failed: %d\n", ret);
+ return ret;
+ }
+
+ ret = stm32_mdma_disable_chan(chan);
+ if (ret < 0)
+ clk_disable_unprepare(dmadev->clk);
+
+ 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);
+ }
+
+ clk_disable_unprepare(dmadev->clk);
+ vchan_free_chan_resources(to_virt_chan(c));
+ dmam_pool_destroy(chan->desc_pool);
+ chan->desc_pool = NULL;
+}
+
+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;
+ 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;
+ }
+
+ 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_get_any_slave_channel(&dmadev->ddev);
+ if (!c) {
+ dev_err(mdma2dev(dmadev), "No more channel avalaible\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,stm32-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;
+ u32 nr_channels, nr_requests;
+ int i, count, ret;
+
+ of_node = pdev->dev.of_node;
+ if (!of_node)
+ return -ENODEV;
+
+ ret = of_property_read_u32(of_node, "dma-channels", &nr_channels);
+ if (ret)
+ nr_channels = STM32_MDMA_MAX_CHANNELS;
+
+ ret = of_property_read_u32(of_node, "dma-requests", &nr_requests);
+ if (ret)
+ nr_requests = STM32_MDMA_MAX_REQUESTS;
+
+ count = of_property_count_u32_elems(of_node, "st,ahb-addr-masks");
+ if (count < 0)
+ count = 0;
+
+ dmadev = devm_kzalloc(&pdev->dev, sizeof(*dmadev) + sizeof(u32) * count,
+ GFP_KERNEL);
+ if (!dmadev)
+ return -ENOMEM;
+
+ dmadev->nr_channels = nr_channels;
+ dmadev->nr_requests = nr_requests;
+ of_property_read_u32_array(of_node, "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)) {
+ dev_err(&pdev->dev, "Error: Missing controller clock\n");
+ return PTR_ERR(dmadev->clk);
+ }
+
+ dmadev->rst = devm_reset_control_get(&pdev->dev, NULL);
+ if (!IS_ERR(dmadev->rst)) {
+ reset_control_assert(dmadev->rst);
+ udelay(2);
+ reset_control_deassert(dmadev->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->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;
+ chan->vchan.desc_free = stm32_mdma_desc_free;
+ vchan_init(&chan->vchan, dd);
+ }
+
+ dmadev->irq = platform_get_irq(pdev, 0);
+ if (dmadev->irq < 0) {
+ dev_err(&pdev->dev, "failed to get IRQ\n");
+ return dmadev->irq;
+ }
+
+ 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");
+ return ret;
+ }
+
+ ret = dma_async_device_register(dd);
+ if (ret)
+ return ret;
+
+ 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_unregister;
+ }
+
+ platform_set_drvdata(pdev, dmadev);
+
+ dev_info(&pdev->dev, "STM32 MDMA driver registered\n");
+
+ return 0;
+
+err_unregister:
+ dma_async_device_unregister(dd);
+
+ return ret;
+}
+
+static struct platform_driver stm32_mdma_driver = {
+ .driver = {
+ .name = "stm32-mdma",
+ .of_match_table = stm32_mdma_of_match,
+ },
+};
+
+static int __init stm32_mdma_init(void)
+{
+ return platform_driver_probe(&stm32_mdma_driver, stm32_mdma_probe);
+}
+
+subsys_initcall(stm32_mdma_init);
--
1.9.1
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