[U-Boot] [PATCH v10 01/28] dma: add bcm6348-iudma support

Álvaro Fernández Rojas noltari at gmail.com
Fri Nov 30 17:13:12 UTC 2018


Hi Daniel,

El 30/11/2018 a las 14:46, Daniel Schwierzeck escribió:
>
> Am 29.11.18 um 23:25 schrieb Álvaro Fernández Rojas:
>> BCM6348 IUDMA controller is present on multiple BMIPS (BCM63xx) SoCs.
>>
>> Signed-off-by: Álvaro Fernández Rojas <noltari at gmail.com>
>> ---
>>   v10: Introduce changes suggested by Daniel Schwierzeck:
>>    - Fix license identifiers.
>>    - Move DMAD_ST defines out of dma desc struct definition.
>>    - Remove unneded aigned attribute from dma desc struct definition.
>>    - Fill dma ring from consumer driver instead of allocating a new buffer.
>>    - Correctly check clock/reset errors while probing.
>>    - Switch to live DM live tree.
>>   v9: introduce dma_prepare_rcv_buf dma op:
>>    - bcm6348_iudma_chan_stop: switch to mdelay when resetting channel.
>>    - bcm6348_iudma_receive: track dirty dma descriptors and no longer trigger
>>     dma rx channel.
>>    - bcm6348_iudma_send: reorder to properly flush cache and set dma descriptor
>>     config.
>>    - bcm6348_iudma_prepare_rcv_buf: implemented to clear dirty dma descriptors.
>>   v8: Introduce changes from Grygorii Strashko
>>   v5: Several fixes and improvements:
>>    - Remove unused defines.
>>    - Increment rx descriptors.
>>    - Fix flow control issues.
>>    - Error checking now depends on hw.
>>    - Remove unneeded interrupts.
>>   v4: Fix issues reported by Grygorii Strashko and other fixes:
>>    - Remove usage of net_rx_packets as buffer.
>>    - Allocate dynamic rx buffer.
>>    - Check dma errors and discard invalid packets.
>>   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 | 642 ++++++++++++++++++++++++++++++++++++++++++++
>>   3 files changed, 652 insertions(+)
>>   create mode 100644 drivers/dma/bcm6348-iudma.c
> Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck at gmail.com>
>
> only one nit left
>
>> diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
>> index 8a4162eccd..1820676d7a 100644
>> --- a/drivers/dma/Kconfig
>> +++ b/drivers/dma/Kconfig
>> @@ -26,6 +26,15 @@ config SANDBOX_DMA
>>   	  Enable support for a test DMA uclass implementation. It stimulates
>>   	  DMA transfer by simple copying data between channels.
>>   
>> +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 aff31f986a..b5f9147e0a 100644
>> --- a/drivers/dma/Makefile
>> +++ b/drivers/dma/Makefile
>> @@ -7,6 +7,7 @@ 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_SANDBOX_DMA) += sandbox-dma-test.o
>>   obj-$(CONFIG_TI_KSNAV) += keystone_nav.o keystone_nav_cfg.o
>> diff --git a/drivers/dma/bcm6348-iudma.c b/drivers/dma/bcm6348-iudma.c
>> new file mode 100644
>> index 0000000000..699f1a6754
>> --- /dev/null
>> +++ b/drivers/dma/bcm6348-iudma.c
>> @@ -0,0 +1,642 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +/*
>> + * Copyright (C) 2018 Álvaro Fernández Rojas <noltari at gmail.com>
>> + *
>> + * Derived from linux/drivers/dma/bcm63xx-iudma.c:
>> + *	Copyright (C) 2015 Simon Arlott <simon at fire.lp0.eu>
>> + *
>> + * Derived from linux/drivers/net/ethernet/broadcom/bcm63xx_enet.c:
>> + *	Copyright (C) 2008 Maxime Bizon <mbizon at 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
>> + */
>> +
>> +#include <common.h>
>> +#include <clk.h>
>> +#include <dm.h>
>> +#include <dma-uclass.h>
>> +#include <memalign.h>
>> +#include <reset.h>
>> +#include <asm/io.h>
>> +
>> +#define DMA_RX_DESC	6
>> +#define DMA_TX_DESC	1
>> +
>> +/* DMA Channels */
>> +#define DMA_CHAN_FLOWC(x)		((x) >> 1)
>> +#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 registers */
>> +#define DMA_FLOWC_THR_LO_REG(x)		(0x04 + DMA_CHAN_FLOWC(x) * 0x0c)
>> +#define DMA_FLOWC_THR_HI_REG(x)		(0x08 + DMA_CHAN_FLOWC(x) * 0x0c)
>> +#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 Max Burst Length register */
>> +#define DMAC_BURST_REG(x)		(DMA_CHAN_SIZE * (x) + 0x0c)
>> +
>> +/* 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)
>> +
>> +/* DMA Descriptor 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)
>> +
>> +#define DMAD6348_ST_OV_ERR_SHIFT	0
>> +#define DMAD6348_ST_OV_ERR_MASK		(1 << DMAD6348_ST_OV_ERR_SHIFT)
>> +#define DMAD6348_ST_CRC_ERR_SHIFT	1
>> +#define DMAD6348_ST_CRC_ERR_MASK	(1 << DMAD6348_ST_CRC_ERR_SHIFT)
>> +#define DMAD6348_ST_RX_ERR_SHIFT	2
>> +#define DMAD6348_ST_RX_ERR_MASK		(1 << DMAD6348_ST_RX_ERR_SHIFT)
>> +#define DMAD6348_ST_OS_ERR_SHIFT	4
>> +#define DMAD6348_ST_OS_ERR_MASK		(1 << DMAD6348_ST_OS_ERR_SHIFT)
>> +#define DMAD6348_ST_UN_ERR_SHIFT	9
>> +#define DMAD6348_ST_UN_ERR_MASK		(1 << DMAD6348_ST_UN_ERR_SHIFT)
>> +
>> +struct bcm6348_dma_desc {
>> +	uint16_t length;
>> +	uint16_t status;
>> +	uint32_t address;
>> +};
>> +
>> +struct bcm6348_chan_priv {
>> +	void __iomem *dma_ring;
>> +	uint8_t dma_ring_size;
>> +	uint8_t desc_id;
>> +	uint8_t desc_cnt;
>> +	bool *busy_desc;
>> +	bool running;
>> +};
>> +
>> +struct bcm6348_iudma_hw {
>> +	uint16_t err_mask;
>> +};
>> +
>> +struct bcm6348_iudma_priv {
>> +	const struct bcm6348_iudma_hw *hw;
>> +	void __iomem *base;
>> +	void __iomem *chan;
>> +	void __iomem *sram;
>> +	struct bcm6348_chan_priv **ch_priv;
>> +	uint8_t n_channels;
>> +};
>> +
>> +static inline bool bcm6348_iudma_chan_is_rx(uint8_t ch)
>> +{
>> +	return !(ch & 1);
>> +}
>> +
>> +static inline void bcm6348_iudma_fdc(void *ptr, ulong size)
>> +{
>> +	ulong start = (ulong) ptr;
>> +
>> +	flush_dcache_range(start, start + size);
>> +}
>> +
>> +static inline void bcm6348_iudma_idc(void *ptr, ulong size)
>> +{
>> +	ulong start = (ulong) ptr;
>> +
>> +	invalidate_dcache_range(start, start + size);
>> +}
>> +
>> +static void bcm6348_iudma_chan_stop(struct bcm6348_iudma_priv *priv,
>> +				    uint8_t ch)
>> +{
>> +	unsigned int timeout = DMA_CHAN_TOUT;
>> +
>> +	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));
>> +	mb();
>> +	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);
>> +	struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
>> +
>> +	/* stop dma channel */
>> +	bcm6348_iudma_chan_stop(priv, dma->id);
>> +
>> +	/* dma flow control */
>> +	if (bcm6348_iudma_chan_is_rx(dma->id))
>> +		writel_be(DMA_FLOWC_ALLOC_FORCE_MASK,
>> +			  DMA_FLOWC_ALLOC_REG(dma->id));
>> +
>> +	/* init channel config */
>> +	ch_priv->running = false;
>> +	ch_priv->desc_id = 0;
>> +	if (bcm6348_iudma_chan_is_rx(dma->id))
>> +		ch_priv->desc_cnt = 0;
>> +	else
>> +		ch_priv->desc_cnt = ch_priv->dma_ring_size;
>> +
>> +	return 0;
>> +}
>> +
>> +static int bcm6348_iudma_enable(struct dma *dma)
>> +{
>> +	const 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 = ch_priv->dma_ring;
>> +	uint8_t i;
>> +
>> +	/* dma ring init */
>> +	for (i = 0; i < ch_priv->desc_cnt; i++) {
>> +		if (bcm6348_iudma_chan_is_rx(dma->id)) {
>> +			ch_priv->busy_desc[i] = false;
>> +			dma_desc->status |= DMAD_ST_OWN_MASK;
>> +		} else {
>> +			dma_desc->status = 0;
>> +			dma_desc->length = 0;
>> +			dma_desc->address = 0;
>> +		}
>> +
>> +		if (i == ch_priv->desc_cnt - 1)
>> +			dma_desc->status |= DMAD_ST_WRAP_MASK;
>> +
>> +		dma_desc++;
>> +	}
>> +
>> +	/* init to first descriptor */
>> +	ch_priv->desc_id = 0;
>> +
>> +	/* force cache writeback */
>> +	bcm6348_iudma_fdc(ch_priv->dma_ring,
>> +			  sizeof(*dma_desc) * ch_priv->desc_cnt);
>> +
>> +	/* 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->desc_cnt / 3;
>> +		writel_be(val, priv->base + DMA_FLOWC_THR_LO_REG(dma->id));
>> +
>> +		val = (ch_priv->desc_cnt * 2) / 3;
>> +		writel_be(val, priv->base + DMA_FLOWC_THR_HI_REG(dma->id));
>> +
>> +		writel_be(0, priv->base + DMA_FLOWC_ALLOC_REG(dma->id));
>> +	}
>> +
>> +	/* set dma max burst */
>> +	writel_be(ch_priv->desc_cnt,
>> +		  priv->chan + DMAC_BURST_REG(dma->id));
>> +
>> +	/* kick rx dma channel */
>> +	if (bcm6348_iudma_chan_is_rx(dma->id))
>> +		setbits_be32(priv->chan + DMAC_CFG_REG(dma->id),
>> +			     DMAC_CFG_ENABLE_MASK);
>> +
>> +	/* channel is now enabled */
>> +	ch_priv->running = true;
>> +
>> +	return 0;
>> +}
>> +
>> +static int bcm6348_iudma_request(struct dma *dma)
>> +{
>> +	const 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 = DMA_RX_DESC;
>> +	else
>> +		ch_priv->dma_ring_size = DMA_TX_DESC;
>> +
>> +	ch_priv->dma_ring =
>> +		malloc_cache_aligned(sizeof(struct bcm6348_dma_desc) *
>> +				     ch_priv->dma_ring_size);
>> +	if (!ch_priv->dma_ring)
>> +		return -ENOMEM;
>> +
>> +	/* init channel config */
>> +	ch_priv->running = false;
>> +	ch_priv->desc_id = 0;
>> +	if (bcm6348_iudma_chan_is_rx(dma->id)) {
>> +		ch_priv->desc_cnt = 0;
>> +		ch_priv->busy_desc = calloc(ch_priv->desc_cnt, sizeof(bool));
>> +	} else {
>> +		ch_priv->desc_cnt = ch_priv->dma_ring_size;
>> +		ch_priv->busy_desc = NULL;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int bcm6348_iudma_receive(struct dma *dma, void **dst, void *metadata)
>> +{
>> +	const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
>> +	const struct bcm6348_iudma_hw *hw = priv->hw;
>> +	struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
>> +	struct bcm6348_dma_desc *dma_desc = dma_desc = ch_priv->dma_ring;
>> +	int ret;
>> +
>> +	/* get dma ring descriptor address */
>> +	dma_desc += ch_priv->desc_id;
>> +
>> +	/* invalidate cache data */
>> +	bcm6348_iudma_idc(dma_desc, sizeof(*dma_desc));
>> +
>> +	/* check dma own */
>> +	if (dma_desc->status & DMAD_ST_OWN_MASK)
>> +		return -EAGAIN;
>> +
>> +	/* check pkt */
>> +	if (!(dma_desc->status & DMAD_ST_EOP_MASK) ||
>> +	    !(dma_desc->status & DMAD_ST_SOP_MASK) ||
>> +	    (dma_desc->status & hw->err_mask)) {
>> +		pr_err("invalid pkt received (ch=%ld desc=%u) (st=%04x)\n",
>> +		       dma->id, ch_priv->desc_id, dma_desc->status);
>> +		ret = -EAGAIN;
>> +	} else {
>> +		/* set dma buffer address */
>> +		*dst = phys_to_virt(dma_desc->address);
>> +
>> +		/* invalidate cache data */
>> +		bcm6348_iudma_idc(*dst, dma_desc->length);
>> +
>> +		/* remove crc */
>> +		ret = dma_desc->length - 4;
> is CRC a feature of the DMA engine or does this belong to the ethernet
> driver?

I would say it belongs to ethernet, since I copied that from linux:

https://github.com/Noltari/linux/blob/master/drivers/net/ethernet/broadcom/bcm63xx_enet.c#L379

However, I just did one version without removing FCS and it worked, so I 
will remove it in the next version.

>
>> +	}
>> +
>> +	/* busy dma descriptor */
>> +	ch_priv->busy_desc[ch_priv->desc_id] = true;
>> +
>> +	/* increment dma descriptor */
>> +	ch_priv->desc_id = (ch_priv->desc_id + 1) % ch_priv->desc_cnt;
>> +
>> +	return ret;
>> +}
>> +
>> +static int bcm6348_iudma_send(struct dma *dma, void *src, size_t len,
>> +			      void *metadata)
>> +{
>> +	const 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 status;
>> +
>> +	/* flush cache */
>> +	bcm6348_iudma_fdc(src, len);
>> +
>> +	/* get dma ring descriptor address */
>> +	dma_desc = ch_priv->dma_ring;
>> +	dma_desc += ch_priv->desc_id;
>> +
>> +	/* config dma descriptor */
>> +	status = (DMAD_ST_OWN_MASK |
>> +		  DMAD_ST_EOP_MASK |
>> +		  DMAD_ST_CRC_MASK |
>> +		  DMAD_ST_SOP_MASK);
>> +	if (ch_priv->desc_id == ch_priv->desc_cnt - 1)
>> +		status |= DMAD_ST_WRAP_MASK;
>> +
>> +	/* set dma descriptor */
>> +	dma_desc->address = virt_to_phys(src);
>> +	dma_desc->length = len;
>> +	dma_desc->status = status;
>> +
>> +	/* flush cache */
>> +	bcm6348_iudma_fdc(dma_desc, sizeof(*dma_desc));
>> +
>> +	/* kick tx dma channel */
>> +	setbits_be32(priv->chan + DMAC_CFG_REG(dma->id), DMAC_CFG_ENABLE_MASK);
>> +
>> +	/* poll dma status */
>> +	do {
>> +		/* invalidate cache */
>> +		bcm6348_iudma_idc(dma_desc, sizeof(*dma_desc));
>> +
>> +		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->desc_cnt;
>> +
>> +	return 0;
>> +}
>> +
>> +static int bcm6348_iudma_free_rcv_buf(struct dma *dma, void *dst, size_t size)
>> +{
>> +	const 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 = ch_priv->dma_ring;
>> +	uint16_t status;
>> +	uint8_t i;
>> +	u32 cfg;
>> +
>> +	/* get dirty dma descriptor */
>> +	for (i = 0; i < ch_priv->desc_cnt; i++) {
>> +		if (phys_to_virt(dma_desc->address) == dst)
>> +			break;
>> +
>> +		dma_desc++;
>> +	}
>> +
>> +	/* dma descriptor not found */
>> +	if (i == ch_priv->desc_cnt) {
>> +		pr_err("dirty dma descriptor not found\n");
>> +		return -ENOENT;
>> +	}
>> +
>> +	/* invalidate cache */
>> +	bcm6348_iudma_idc(ch_priv->dma_ring,
>> +			  sizeof(*dma_desc) * ch_priv->desc_cnt);
>> +
>> +	/* free dma descriptor */
>> +	ch_priv->busy_desc[i] = false;
>> +
>> +	status = DMAD_ST_OWN_MASK;
>> +	if (i == ch_priv->desc_cnt - 1)
>> +		status |= DMAD_ST_WRAP_MASK;
>> +
>> +	dma_desc->status |= status;
>> +	dma_desc->length = PKTSIZE_ALIGN;
>> +
>> +	/* tell dma we allocated one buffer */
>> +	writel_be(1, DMA_FLOWC_ALLOC_REG(dma->id));
>> +
>> +	/* flush cache */
>> +	bcm6348_iudma_fdc(ch_priv->dma_ring,
>> +			  sizeof(*dma_desc) * ch_priv->desc_cnt);
>> +
>> +	/* kick rx dma channel if disabled */
>> +	cfg = readl_be(priv->chan + DMAC_CFG_REG(dma->id));
>> +	if (!(cfg & DMAC_CFG_ENABLE_MASK))
>> +		setbits_be32(priv->chan + DMAC_CFG_REG(dma->id),
>> +			     DMAC_CFG_ENABLE_MASK);
>> +
>> +	return 0;
>> +}
>> +
>> +static int bcm6348_iudma_add_rcv_buf(struct dma *dma, void *dst, size_t size)
>> +{
>> +	const 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 = ch_priv->dma_ring;
>> +
>> +	/* no more dma descriptors available */
>> +	if (ch_priv->desc_cnt == ch_priv->dma_ring_size) {
>> +		pr_err("max number of buffers reached\n");
>> +		return -EINVAL;
>> +	}
>> +
>> +	/* get next dma descriptor */
>> +	dma_desc += ch_priv->desc_cnt;
>> +
>> +	/* init dma descriptor */
>> +	dma_desc->address = virt_to_phys(dst);
>> +	dma_desc->length = size;
>> +	dma_desc->status = 0;
>> +
>> +	/* flush cache */
>> +	bcm6348_iudma_fdc(dma_desc, sizeof(*dma_desc));
>> +
>> +	/* increment dma descriptors */
>> +	ch_priv->desc_cnt++;
>> +
>> +	return 0;
>> +}
>> +
>> +static int bcm6348_iudma_prepare_rcv_buf(struct dma *dma, void *dst,
>> +					 size_t size)
>> +{
>> +	const struct bcm6348_iudma_priv *priv = dev_get_priv(dma->dev);
>> +	struct bcm6348_chan_priv *ch_priv = priv->ch_priv[dma->id];
>> +
>> +	/* only add new rx buffers if channel isn't running */
>> +	if (ch_priv->running)
>> +		return bcm6348_iudma_free_rcv_buf(dma, dst, size);
>> +	else
>> +		return bcm6348_iudma_add_rcv_buf(dma, dst, size);
>> +}
>> +
>> +static const struct dma_ops bcm6348_iudma_ops = {
>> +	.disable = bcm6348_iudma_disable,
>> +	.enable = bcm6348_iudma_enable,
>> +	.prepare_rcv_buf = bcm6348_iudma_prepare_rcv_buf,
>> +	.request = bcm6348_iudma_request,
>> +	.receive = bcm6348_iudma_receive,
>> +	.send = bcm6348_iudma_send,
>> +};
>> +
>> +static const struct bcm6348_iudma_hw bcm6348_hw = {
>> +	.err_mask = (DMAD6348_ST_OV_ERR_MASK |
>> +		     DMAD6348_ST_CRC_ERR_MASK |
>> +		     DMAD6348_ST_RX_ERR_MASK |
>> +		     DMAD6348_ST_OS_ERR_MASK |
>> +		     DMAD6348_ST_UN_ERR_MASK),
>> +};
>> +
>> +static const struct bcm6348_iudma_hw bcm6368_hw = {
>> +	.err_mask = 0,
>> +};
>> +
>> +static const struct udevice_id bcm6348_iudma_ids[] = {
>> +	{
>> +		.compatible = "brcm,bcm6348-iudma",
>> +		.data = (ulong)&bcm6348_hw,
>> +	}, {
>> +		.compatible = "brcm,bcm6368-iudma",
>> +		.data = (ulong)&bcm6368_hw,
>> +	}, { /* 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);
>> +	const struct bcm6348_iudma_hw *hw =
>> +		(const struct bcm6348_iudma_hw *)dev_get_driver_data(dev);
>> +	uint8_t ch;
>> +	int i;
>> +
>> +	uc_priv->supported = (DMA_SUPPORTS_DEV_TO_MEM |
>> +			      DMA_SUPPORTS_MEM_TO_DEV);
>> +	priv->hw = hw;
>> +
>> +	/* dma global base address */
>> +	priv->base = dev_remap_addr_name(dev, "dma");
>> +	if (!priv->base)
>> +		return -EINVAL;
>> +
>> +	/* dma channels base address */
>> +	priv->chan = dev_remap_addr_name(dev, "dma-channels");
>> +	if (!priv->chan)
>> +		return -EINVAL;
>> +
>> +	/* dma sram base address */
>> +	priv->sram = dev_remap_addr_name(dev, "dma-sram");
>> +	if (!priv->sram)
>> +		return -EINVAL;
>> +
>> +	/* get number of channels */
>> +	priv->n_channels = dev_read_u32_default(dev, "dma-channels", 8);
>> +	if (priv->n_channels > DMA_CHAN_MAX)
>> +		return -EINVAL;
>> +
>> +	/* 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;
>> +
>> +		ret = clk_enable(&clk);
>> +		if (ret < 0) {
>> +			pr_err("error enabling clock %d\n", i);
>> +			return ret;
>> +		}
>> +
>> +		ret = clk_free(&clk);
>> +		if (ret < 0) {
>> +			pr_err("error freeing clock %d\n", i);
>> +			return ret;
>> +		}
>> +	}
>> +
>> +	/* 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;
>> +
>> +		ret = reset_deassert(&reset);
>> +		if (ret < 0) {
>> +			pr_err("error deasserting reset %d\n", i);
>> +			return ret;
>> +		}
>> +
>> +		ret = reset_free(&reset);
>> +		if (ret < 0) {
>> +			pr_err("error freeing reset %d\n", i);
>> +			return ret;
>> +		}
>> +	}
>> +
>> +	/* disable dma controller */
>> +	clrbits_be32(priv->base + DMA_CFG_REG, DMA_CFG_ENABLE_MASK);
>> +
>> +	/* 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,
>> +};
>>


More information about the U-Boot mailing list