[U-Boot] [RFC v3 03/15] dma: add bcm6348-iudma support

Álvaro Fernández Rojas
2018-02-21T16:10:28Z

BCM6348 IUDMA controller is present on multiple BMIPS (BCM63xx) SoCs.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
---
v3: no changes
v2: Fix dma rx burst config and select DMA_CHANNELS.

drivers/dma/Kconfig | 9 +
drivers/dma/Makefile | 1 +
drivers/dma/bcm6348-iudma.c | 505 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 515 insertions(+)
create mode 100644 drivers/dma/bcm6348-iudma.c

diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 21b2c0dcaa..9afa158b51 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -19,6 +19,15 @@ config DMA_CHANNELS
Enable channels support for DMA. Some DMA controllers have multiple
channels which can either transfer data to/from different devices.

+config BCM6348_IUDMA
+ bool "BCM6348 IUDMA driver"
+ depends on ARCH_BMIPS
+ select DMA_CHANNELS
+ help
+ Enable the BCM6348 IUDMA driver.
+ This driver support data transfer from devices to
+ memory and from memory to devices.
+
config TI_EDMA3
bool "TI EDMA3 driver"
help
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index 39b78b2a3d..b2b4147349 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_DMA) += dma-uclass.o

obj-$(CONFIG_FSLDMAFEC) += MCD_tasksInit.o MCD_dmaApi.o MCD_tasks.o
obj-$(CONFIG_APBH_DMA) += apbh_dma.o
+obj-$(CONFIG_BCM6348_IUDMA) += bcm6348-iudma.o
obj-$(CONFIG_FSL_DMA) += fsl_dma.o
obj-$(CONFIG_TI_KSNAV) += keystone_nav.o keystone_nav_cfg.o
obj-$(CONFIG_TI_EDMA3) += ti-edma3.o
diff --git a/drivers/dma/bcm6348-iudma.c b/drivers/dma/bcm6348-iudma.c
new file mode 100644
index 0000000000..8016a58be2
--- /dev/null
+++ b/drivers/dma/bcm6348-iudma.c
@@ -0,0 +1,505 @@
+/*
+ * Copyright (C) 2018 Álvaro Fernández Rojas <noltari@gmail.com>
+ *
+ * Derived from linux/drivers/dma/bcm63xx-iudma.c:
+ * Copyright (C) 2015 Simon Arlott <simon@fire.lp0.eu>
+ *
+ * Derived from linux/drivers/net/ethernet/broadcom/bcm63xx_enet.c:
+ * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
+ *
+ * Derived from bcm963xx_4.12L.06B_consumer/shared/opensource/include/bcm963xx/63268_map_part.h:
+ * Copyright (C) 2000-2010 Broadcom Corporation
+ *
+ * Derived from bcm963xx_4.12L.06B_consumer/bcmdrivers/opensource/net/enet/impl4/bcmenet.c:
+ * Copyright (C) 2010 Broadcom Corporation
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <dm.h>
+#include <dma-uclass.h>
+#include <memalign.h>
+#include <net.h>
+#include <reset.h>
+#include <asm/io.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define ALIGN_END_ADDR(type, ptr, size) \
+ ((unsigned long)(ptr) + roundup((size) * sizeof(type), \
+ ARCH_DMA_MINALIGN))
+
+/* DMA Channels */
+#define DMA_CHAN_FLOWC(x) ((x) >> 1)
+#define DMA_CHAN_FLOWC_MAX 8
+#define DMA_CHAN_MAX 16
+#define DMA_CHAN_SIZE 0x10
+#define DMA_CHAN_TOUT 500
+
+/* DMA Global Configuration register */
+#define DMA_CFG_REG 0x00
+#define DMA_CFG_ENABLE_SHIFT 0
+#define DMA_CFG_ENABLE_MASK (1 << DMA_CFG_ENABLE_SHIFT)
+#define DMA_CFG_FLOWC_ENABLE(x) BIT(DMA_CHAN_FLOWC(x) + 1)
+#define DMA_CFG_NCHANS_SHIFT 24
+#define DMA_CFG_NCHANS_MASK (0xf << DMA_CFG_NCHANS_SHIFT)
+
+/* DMA Global Flow Control Threshold registers */
+#define DMA_FLOWC_THR_LO_REG(x) (0x04 + DMA_CHAN_FLOWC(x) * 0x0c)
+#define DMA_FLOWC_THR_LO_SHIFT 0
+#define DMA_FLOWC_THR_LO_MASK (5 << DMA_FLOWC_THR_LO_SHIFT)
+
+#define DMA_FLOWC_THR_HI_REG(x) (0x08 + DMA_CHAN_FLOWC(x) * 0x0c)
+#define DMA_FLOWC_THR_HI_SHIFT 0
+#define DMA_FLOWC_THR_HI_MASK (10 << DMA_FLOWC_THR_HI_SHIFT)
+
+/* DMA Global Flow Control Buffer Allocation registers */
+#define DMA_FLOWC_ALLOC_REG(x) (0x0c + DMA_CHAN_FLOWC(x) * 0x0c)
+#define DMA_FLOWC_ALLOC_FORCE_SHIFT 31
+#define DMA_FLOWC_ALLOC_FORCE_MASK (1 << DMA_FLOWC_ALLOC_FORCE_SHIFT)
+
+/* DMA Global Reset register */
+#define DMA_RST_REG 0x34
+#define DMA_RST_CHAN_SHIFT 0
+#define DMA_RST_CHAN_MASK(x) (1 << x)
+
+/* DMA Channel Configuration register */
+#define DMAC_CFG_REG(x) (DMA_CHAN_SIZE * (x) + 0x00)
+#define DMAC_CFG_ENABLE_SHIFT 0
+#define DMAC_CFG_ENABLE_MASK (1 << DMAC_CFG_ENABLE_SHIFT)
+#define DMAC_CFG_PKT_HALT_SHIFT 1
+#define DMAC_CFG_PKT_HALT_MASK (1 << DMAC_CFG_PKT_HALT_SHIFT)
+#define DMAC_CFG_BRST_HALT_SHIFT 2
+#define DMAC_CFG_BRST_HALT_MASK (1 << DMAC_CFG_BRST_HALT_SHIFT)
+
+/* DMA Channel Interrupts registers */
+#define DMAC_IR_ST_REG(x) (DMA_CHAN_SIZE * (x) + 0x04)
+#define DMAC_IR_EN_REG(x) (DMA_CHAN_SIZE * (x) + 0x08)
+
+#define DMAC_IR_DONE_SHIFT 2
+#define DMAC_IR_DONE_MASK (1 << DMAC_IR_DONE_SHIFT)
+
+/* DMA Channel Max Burst Length register */
+#define DMAC_BURST_REG(x) (DMA_CHAN_SIZE * (x) + 0x0c)
+#define DMAC_BURST_MAX_SHIFT 0
+#define DMAC_BURST_MAX_MASK (16 << DMAC_BURST_MAX_SHIFT)
+
+/* DMA SRAM Descriptor Ring Start register */
+#define DMAS_RSTART_REG(x) (DMA_CHAN_SIZE * (x) + 0x00)
+
+/* DMA SRAM State/Bytes done/ring offset register */
+#define DMAS_STATE_DATA_REG(x) (DMA_CHAN_SIZE * (x) + 0x04)
+
+/* DMA SRAM Buffer Descriptor status and length register */
+#define DMAS_DESC_LEN_STATUS_REG(x) (DMA_CHAN_SIZE * (x) + 0x08)
+
+/* DMA SRAM Buffer Descriptor status and length register */
+#define DMAS_DESC_BASE_BUFPTR_REG(x) (DMA_CHAN_SIZE * (x) + 0x0c)
+
+struct bcm6348_dma_desc {
+ uint16_t length;
+
+ uint16_t status;
+#define DMAD_ST_CRC_SHIFT 8
+#define DMAD_ST_CRC_MASK (1 << DMAD_ST_CRC_SHIFT)
+#define DMAD_ST_WRAP_SHIFT 12
+#define DMAD_ST_WRAP_MASK (1 << DMAD_ST_WRAP_SHIFT)
+#define DMAD_ST_SOP_SHIFT 13
+#define DMAD_ST_SOP_MASK (1 << DMAD_ST_SOP_SHIFT)
+#define DMAD_ST_EOP_SHIFT 14
+#define DMAD_ST_EOP_MASK (1 << DMAD_ST_EOP_SHIFT)
+#define DMAD_ST_OWN_SHIFT 15
+#define DMAD_ST_OWN_MASK (1 << DMAD_ST_OWN_SHIFT)
+
+ uint32_t address;
+} __attribute__((aligned(1)));
+
+struct bcm6348_chan_priv {
+ void __iomem *dma_ring;
+ uint8_t dma_ring_size;
+ uint8_t desc_id;
+};
+
+struct bcm6348_iudma_priv {
+ void __iomem *base;
+ void __iomem *chan;
+ void __iomem *sram;
+ struct bcm6348_chan_priv **ch_priv;
+ uint8_t n_channels;
+};
+
+static bool bcm6348_iudma_chan_is_rx(uint8_t ch)
+{
+ return !(ch & 1);
+}
+
+static void bcm6348_iudma_chan_stop(struct bcm6348_iudma_priv *priv,
+ uint8_t ch)
+{
+ unsigned int timeout = DMA_CHAN_TOUT;
+
+ /* disable dma channel interrupts */
+ writel_be(0, priv->chan + DMAC_IR_EN_REG(ch));
+
+ do {
+ uint32_t cfg, halt;
+
+ if (timeout > DMA_CHAN_TOUT / 2)
+ halt = DMAC_CFG_PKT_HALT_MASK;
+ else
+ halt = DMAC_CFG_BRST_HALT_MASK;
+
+ /* try to stop dma channel */
+ writel_be(halt, priv->chan + DMAC_CFG_REG(ch));
+ mb();
+
+ /* check if channel was stopped */
+ cfg = readl_be(priv->chan + DMAC_CFG_REG(ch));
+ if (!(cfg & DMAC_CFG_ENABLE_MASK))
+ break;
+
+ udelay(1);
+ } while (--timeout);
+
+ if (!timeout)
+ pr_err("unable to stop channel %u\n", ch);
+
+ /* reset dma channel */
+ setbits_be32(priv->base + DMA_RST_REG, DMA_RST_CHAN_MASK(ch));
+ clrbits_be32(priv->base + DMA_RST_REG, DMA_RST_CHAN_MASK(ch));
+}
+
+static int bcm6348_iudma_disable(struct dma *dma)
+{
+ struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
+
+ bcm6348_iudma_chan_stop(priv, dma->id);
+
+ if (bcm6348_iudma_chan_is_rx(dma->id))
+ writel_be(DMA_FLOWC_ALLOC_FORCE_MASK,
+ DMA_FLOWC_ALLOC_REG(dma->id));
+
+ return 0;
+}
+
+static int bcm6348_iudma_enable(struct dma *dma)
+{
+ struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
+ struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
+ struct bcm6348_dma_desc *dma_desc;
+ uint8_t i;
+
+ /* init dma rings */
+ dma_desc = ch_priv->dma_ring;
+ for (i = 0; i < ch_priv->dma_ring_size; i++) {
+ if (bcm6348_iudma_chan_is_rx(dma->id)) {
+ dma_desc->status = DMAD_ST_OWN_MASK;
+ dma_desc->length = PKTSIZE_ALIGN;
+ dma_desc->address = virt_to_phys(net_rx_packets[i]);
+ } else {
+ dma_desc->status = 0;
+ dma_desc->length = 0;
+ dma_desc->address = 0;
+ }
+
+ if (i == ch_priv->dma_ring_size - 1)
+ dma_desc->status |= DMAD_ST_WRAP_MASK;
+
+ if (bcm6348_iudma_chan_is_rx(dma->id))
+ writel_be(1,
+ priv->base + DMA_FLOWC_ALLOC_REG(dma->id));
+
+ dma_desc++;
+ }
+
+ /* init to first descriptor */
+ ch_priv->desc_id = 0;
+
+ /* force cache writeback */
+ flush_dcache_range((ulong)ch_priv->dma_ring,
+ ALIGN_END_ADDR(struct bcm6348_dma_desc, ch_priv->dma_ring,
+ ch_priv->dma_ring_size));
+
+ /* clear sram */
+ writel_be(0, priv->sram + DMAS_STATE_DATA_REG(dma->id));
+ writel_be(0, priv->sram + DMAS_DESC_LEN_STATUS_REG(dma->id));
+ writel_be(0, priv->sram + DMAS_DESC_BASE_BUFPTR_REG(dma->id));
+
+ /* set dma ring start */
+ writel_be(virt_to_phys(ch_priv->dma_ring),
+ priv->sram + DMAS_RSTART_REG(dma->id));
+
+ /* set flow control */
+ if (bcm6348_iudma_chan_is_rx(dma->id)) {
+ u32 val;
+
+ setbits_be32(priv->base + DMA_CFG_REG,
+ DMA_CFG_FLOWC_ENABLE(dma->id));
+
+ val = ch_priv->dma_ring_size / 3;
+ writel_be(val, priv->base + DMA_FLOWC_THR_LO_REG(dma->id));
+
+ val = (ch_priv->dma_ring_size * 2) / 3;
+ writel_be(val, priv->base + DMA_FLOWC_THR_HI_REG(dma->id));
+ }
+
+ /* set dma max burst */
+ writel_be(ch_priv->dma_ring_size,
+ priv->chan + DMAC_BURST_REG(dma->id));
+
+ /* clear interrupts */
+ writel_be(DMAC_IR_DONE_MASK, priv->chan + DMAC_IR_ST_REG(dma->id));
+ writel_be(0, priv->chan + DMAC_IR_EN_REG(dma->id));
+
+ setbits_be32(priv->chan + DMAC_CFG_REG(dma->id), DMAC_CFG_ENABLE_MASK);
+
+ return 0;
+}
+
+static int bcm6348_iudma_request(struct dma *dma)
+{
+ struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
+ struct bcm6348_chan_priv *ch_priv;
+
+ /* check if channel is valid */
+ if (dma->id >= priv->n_channels)
+ return -ENODEV;
+
+ /* alloc channel private data */
+ priv->ch_priv[dma->id] = calloc(1, sizeof(struct bcm6348_chan_priv));
+ if (!priv->ch_priv[dma->id])
+ return -ENOMEM;
+ ch_priv = priv->ch_priv[dma->id];
+
+ /* alloc dma ring */
+ if (bcm6348_iudma_chan_is_rx(dma->id))
+ ch_priv->dma_ring_size = PKTBUFSRX;
+ else
+ ch_priv->dma_ring_size = 1;
+ ch_priv->dma_ring =
+ malloc_cache_aligned(sizeof(struct bcm6348_dma_desc) *
+ ch_priv->dma_ring_size);
+ if (!ch_priv->dma_ring)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static int bcm6348_iudma_receive(struct dma *dma, void **dst)
+{
+ struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
+ struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
+ struct bcm6348_dma_desc *dma_desc;
+ void __iomem *dma_buff;
+ uint16_t status;
+ int ret;
+
+ /* get dma ring descriptor address */
+ dma_desc = ch_priv->dma_ring;
+ dma_desc += ch_priv->desc_id;
+
+ /* invalidate cache data */
+ invalidate_dcache_range((ulong)dma_desc,
+ ALIGN_END_ADDR(struct bcm6348_dma_desc, dma_desc, 1));
+
+ /* check dma own */
+ if (dma_desc->status & DMAD_ST_OWN_MASK)
+ return 0;
+
+ /* check dma end */
+ if (!(dma_desc->status & DMAD_ST_EOP_MASK))
+ return -EINVAL;
+
+ /* get dma buff descriptor address */
+ dma_buff = phys_to_virt(dma_desc->address);
+
+ /* invalidate cache data */
+ invalidate_dcache_range((ulong)dma_buff,
+ (ulong)(dma_buff + PKTSIZE_ALIGN));
+
+ /* get dma data */
+ *dst = dma_buff;
+ ret = dma_desc->length;
+
+ /* reinit dma descriptor */
+ status = dma_desc->status & DMAD_ST_WRAP_MASK;
+ status |= DMAD_ST_OWN_MASK;
+
+ dma_desc->length = PKTSIZE_ALIGN;
+ dma_desc->status = status;
+
+ /* flush cache */
+ flush_dcache_range((ulong)dma_desc,
+ ALIGN_END_ADDR(struct bcm6348_dma_desc, dma_desc, 1));
+
+ /* set flow control buffer alloc */
+ writel_be(1, priv->base + DMA_FLOWC_ALLOC_REG(dma->id));
+
+ /* enable dma */
+ setbits_be32(priv->chan + DMAC_CFG_REG(dma->id), DMAC_CFG_ENABLE_MASK);
+
+ /* set interrupt */
+ writel_be(DMAC_IR_DONE_MASK, priv->chan + DMAC_IR_EN_REG(dma->id));
+
+ /* increment dma descriptor */
+ ch_priv->desc_id = (ch_priv->desc_id + 1) % ch_priv->dma_ring_size;
+
+ return ret - 4;
+}
+
+static int bcm6348_iudma_send(struct dma *dma, void *src, size_t len)
+{
+ struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
+ struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
+ struct bcm6348_dma_desc *dma_desc;
+ uint16_t val;
+
+ /* get dma ring descriptor address */
+ dma_desc = ch_priv->dma_ring;
+ dma_desc += ch_priv->desc_id;
+
+ dma_desc->address = virt_to_phys(src);
+
+ /* config dma descriptor */
+ val = (DMAD_ST_OWN_MASK |
+ DMAD_ST_EOP_MASK |
+ DMAD_ST_CRC_MASK |
+ DMAD_ST_SOP_MASK);
+ if (ch_priv->desc_id == ch_priv->dma_ring_size - 1)
+ val |= DMAD_ST_WRAP_MASK;
+
+ dma_desc->length = len;
+ dma_desc->status = val;
+
+ /* flush cache */
+ flush_dcache_range((ulong)src, (ulong)src + PKTSIZE_ALIGN);
+
+ /* flush cache */
+ flush_dcache_range((ulong)dma_desc,
+ ALIGN_END_ADDR(struct bcm6348_dma_desc, dma_desc, 1));
+
+ /* enable dma */
+ setbits_be32(priv->chan + DMAC_CFG_REG(dma->id), DMAC_CFG_ENABLE_MASK);
+
+ /* set interrupt */
+ writel_be(DMAC_IR_DONE_MASK, priv->chan + DMAC_IR_EN_REG(dma->id));
+
+ /* poll dma status */
+ do {
+ /* invalidate cache */
+ invalidate_dcache_range((ulong)dma_desc,
+ ALIGN_END_ADDR(struct bcm6348_dma_desc, dma_desc, 1));
+
+ if (!(dma_desc->status & DMAD_ST_OWN_MASK))
+ break;
+ } while(1);
+
+ /* increment dma descriptor */
+ ch_priv->desc_id = (ch_priv->desc_id + 1) % ch_priv->dma_ring_size;
+
+ return 0;
+}
+
+static const struct dma_ops bcm6348_iudma_ops = {
+ .disable = bcm6348_iudma_disable,
+ .enable = bcm6348_iudma_enable,
+ .request = bcm6348_iudma_request,
+ .receive = bcm6348_iudma_receive,
+ .send = bcm6348_iudma_send,
+};
+
+static const struct udevice_id bcm6348_iudma_ids[] = {
+ { .compatible = "brcm,bcm6348-iudma", },
+ { /* sentinel */ }
+};
+
+static int bcm6348_iudma_probe(struct udevice *dev)
+{
+ struct dma_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+ struct bcm6348_iudma_priv *priv = dev_get_priv(dev);
+ fdt_addr_t addr;
+ uint8_t ch;
+ int i;
+
+ uc_priv->supported = DMA_SUPPORTS_DEV_TO_MEM |
+ DMA_SUPPORTS_MEM_TO_DEV;
+
+ /* try to enable clocks */
+ for (i = 0; ; i++) {
+ struct clk clk;
+ int ret;
+
+ ret = clk_get_by_index(dev, i, &clk);
+ if (ret < 0)
+ break;
+ if (clk_enable(&clk))
+ pr_err("failed to enable clock %d\n", i);
+ clk_free(&clk);
+ }
+
+ /* try to perform resets */
+ for (i = 0; ; i++) {
+ struct reset_ctl reset;
+ int ret;
+
+ ret = reset_get_by_index(dev, i, &reset);
+ if (ret < 0)
+ break;
+ if (reset_deassert(&reset))
+ pr_err("failed to deassert reset %d\n", i);
+ reset_free(&reset);
+ }
+
+ /* dma global base address */
+ addr = devfdt_get_addr_name(dev, "dma");
+ if (addr == FDT_ADDR_T_NONE)
+ return -EINVAL;
+ priv->base = ioremap(addr, 0);
+
+ /* dma channels base address */
+ addr = devfdt_get_addr_name(dev, "dma-channels");
+ if (addr == FDT_ADDR_T_NONE)
+ return -EINVAL;
+ priv->chan = ioremap(addr, 0);
+
+ /* dma sram base address */
+ addr = devfdt_get_addr_name(dev, "dma-sram");
+ if (addr == FDT_ADDR_T_NONE)
+ return -EINVAL;
+ priv->sram = ioremap(addr, 0);
+
+ /* disable dma controller */
+ clrbits_be32(priv->base + DMA_CFG_REG, DMA_CFG_ENABLE_MASK);
+
+ /* get number of channels */
+ priv->n_channels = fdtdec_get_uint(gd->fdt_blob, dev_of_offset(dev),
+ "dma-channels", 8);
+ if (priv->n_channels > DMA_CHAN_MAX)
+ return -EINVAL;
+
+ /* alloc channel private data pointers */
+ priv->ch_priv = calloc(priv->n_channels,
+ sizeof(struct bcm6348_chan_priv*));
+ if (!priv->ch_priv)
+ return -ENOMEM;
+
+ /* stop dma channels */
+ for (ch = 0; ch < priv->n_channels; ch++)
+ bcm6348_iudma_chan_stop(priv, ch);
+
+ /* enable dma controller */
+ setbits_be32(priv->base + DMA_CFG_REG, DMA_CFG_ENABLE_MASK);
+
+ return 0;
+}
+
+U_BOOT_DRIVER(bcm6348_iudma) = {
+ .name = "bcm6348_iudma",
+ .id = UCLASS_DMA,
+ .of_match = bcm6348_iudma_ids,
+ .ops = &bcm6348_iudma_ops,
+ .priv_auto_alloc_size = sizeof(struct bcm6348_iudma_priv),
+ .probe = bcm6348_iudma_probe,
+};
--
2.11.0