On 27-08-24, 14:49, Inochi Amaoto wrote:
> Sophgo CV18XX/SG200X use DW AXI CORE with a multiplexer for remapping
> its request lines. The multiplexer supports at most 8 request lines.
>
> Add driver for Sophgo CV18XX/SG200X DMA multiplexer.
>
> Signed-off-by: Inochi Amaoto <inochiama@xxxxxxxxxxx>
> ---
> drivers/dma/Kconfig | 9 ++
> drivers/dma/Makefile | 1 +
> drivers/dma/cv1800-dmamux.c | 257 ++++++++++++++++++++++++++++++++++++
> 3 files changed, 267 insertions(+)
> create mode 100644 drivers/dma/cv1800-dmamux.c
>
> diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
> index cc0a62c34861..df010ee1de46 100644
> --- a/drivers/dma/Kconfig
> +++ b/drivers/dma/Kconfig
> @@ -546,6 +546,15 @@ config PLX_DMA
> These are exposed via extra functions on the switch's
> upstream port. Each function exposes one DMA channel.
>
> +config SOPHGO_CV1800_DMAMUX
> + tristate "Sophgo CV1800/SG2000 series SoC DMA multiplexer support"
> + depends on MFD_SYSCON
> + depends on ARCH_SOPHGO
this lgtm, maybe add || COMPILE_TEST for wider compile test coverage?
> + help
> + Support for the DMA multiplexer on Sophgo CV1800/SG2000
> + series SoCs.
> + Say Y here if your board have this soc.
> +
> config STE_DMA40
> bool "ST-Ericsson DMA40 support"
> depends on ARCH_U8500
> diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
> index 374ea98faf43..60d05b305082 100644
> --- a/drivers/dma/Makefile
> +++ b/drivers/dma/Makefile
> @@ -69,6 +69,7 @@ obj-$(CONFIG_PPC_BESTCOMM) += bestcomm/
> obj-$(CONFIG_PXA_DMA) += pxa_dma.o
> obj-$(CONFIG_RENESAS_DMA) += sh/
> obj-$(CONFIG_SF_PDMA) += sf-pdma/
> +obj-$(CONFIG_SOPHGO_CV1800_DMAMUX) += cv1800-dmamux.o
> obj-$(CONFIG_STE_DMA40) += ste_dma40.o ste_dma40_ll.o
> obj-$(CONFIG_SPRD_DMA) += sprd-dma.o
> obj-$(CONFIG_TXX9_DMAC) += txx9dmac.o
> diff --git a/drivers/dma/cv1800-dmamux.c b/drivers/dma/cv1800-dmamux.c
> new file mode 100644
> index 000000000000..a907c72325c7
> --- /dev/null
> +++ b/drivers/dma/cv1800-dmamux.c
> @@ -0,0 +1,257 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2024 Inochi Amaoto <inochiama@xxxxxxxxxxx>
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/cleanup.h>
> +#include <linux/module.h>
> +#include <linux/of_dma.h>
> +#include <linux/of_address.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/llist.h>
> +#include <linux/regmap.h>
> +#include <linux/spinlock.h>
> +#include <linux/mfd/syscon.h>
> +
> +#include <soc/sophgo/cv1800-sysctl.h>
> +
> +#define DMAMUX_NCELLS 2
> +#define MAX_DMA_MAPPING_ID 42
> +#define MAX_DMA_CPU_ID 2
> +#define MAX_DMA_CH_ID 7
> +
> +#define DMAMUX_INTMUX_REGISTER_LEN 4
> +#define DMAMUX_NR_CH_PER_REGISTER 4
> +#define DMAMUX_BIT_PER_CH 8
> +#define DMAMUX_CH_MASk GENMASK(5, 0)
> +#define DMAMUX_INT_BIT_PER_CPU 10
> +#define DMAMUX_CH_UPDATE_BIT BIT(31)
> +
> +#define DMAMUX_CH_REGPOS(chid) \
> + ((chid) / DMAMUX_NR_CH_PER_REGISTER)
> +#define DMAMUX_CH_REGOFF(chid) \
> + ((chid) % DMAMUX_NR_CH_PER_REGISTER)
> +#define DMAMUX_CH_REG(chid) \
> + ((DMAMUX_CH_REGPOS(chid) * sizeof(u32)) + \
> + CV1800_SDMA_DMA_CHANNEL_REMAP0)
> +#define DMAMUX_CH_SET(chid, val) \
> + (((val) << (DMAMUX_CH_REGOFF(chid) * DMAMUX_BIT_PER_CH)) | \
> + DMAMUX_CH_UPDATE_BIT)
> +#define DMAMUX_CH_MASK(chid) \
> + DMAMUX_CH_SET(chid, DMAMUX_CH_MASk)
> +
> +#define DMAMUX_INT_BIT(chid, cpuid) \
> + BIT((cpuid) * DMAMUX_INT_BIT_PER_CPU + (chid))
> +#define DMAMUX_INTEN_BIT(cpuid) \
> + DMAMUX_INT_BIT(8, cpuid)
> +#define DMAMUX_INT_CH_BIT(chid, cpuid) \
> + (DMAMUX_INT_BIT(chid, cpuid) | DMAMUX_INTEN_BIT(cpuid))
> +#define DMAMUX_INT_MASK(chid) \
> + (DMAMUX_INT_BIT(chid, 0) | \
> + DMAMUX_INT_BIT(chid, 1) | \
> + DMAMUX_INT_BIT(chid, 2))
> +#define DMAMUX_INT_CH_MASK(chid, cpuid) \
> + (DMAMUX_INT_MASK(chid) | DMAMUX_INTEN_BIT(cpuid))
> +
> +struct cv1800_dmamux_data {
> + struct dma_router dmarouter;
> + struct regmap *regmap;
> + spinlock_t lock;
> + struct llist_head free_maps;
> + struct llist_head reserve_maps;
> + DECLARE_BITMAP(mapped_peripherals, MAX_DMA_MAPPING_ID);
> +};
> +
> +struct cv1800_dmamux_map {
> + struct llist_node node;
> + unsigned int channel;
> + unsigned int peripheral;
> + unsigned int cpu;
> +};
> +
> +static void cv1800_dmamux_free(struct device *dev, void *route_data)
> +{
> + struct cv1800_dmamux_data *dmamux = dev_get_drvdata(dev);
> + struct cv1800_dmamux_map *map = route_data;
> +
> + guard(spinlock_irqsave)(&dmamux->lock);
> +
> + regmap_update_bits(dmamux->regmap,
> + DMAMUX_CH_REG(map->channel),
> + DMAMUX_CH_MASK(map->channel),
> + DMAMUX_CH_UPDATE_BIT);
> +
> + regmap_update_bits(dmamux->regmap, CV1800_SDMA_DMA_INT_MUX,
> + DMAMUX_INT_CH_MASK(map->channel, map->cpu),
> + DMAMUX_INTEN_BIT(map->cpu));
> +
> + dev_dbg(dev, "free channel %u for req %u (cpu %u)\n",
> + map->channel, map->peripheral, map->cpu);
> +}
> +
> +static void *cv1800_dmamux_route_allocate(struct of_phandle_args *dma_spec,
> + struct of_dma *ofdma)
> +{
> + struct platform_device *pdev = of_find_device_by_node(ofdma->of_node);
> + struct cv1800_dmamux_data *dmamux = platform_get_drvdata(pdev);
> + struct cv1800_dmamux_map *map;
> + struct llist_node *node;
> + unsigned long flags;
> + unsigned int chid, devid, cpuid;
> + int ret;
> +
> + if (dma_spec->args_count != DMAMUX_NCELLS) {
> + dev_err(&pdev->dev, "invalid number of dma mux args\n");
> + return ERR_PTR(-EINVAL);
> + }
> +
> + devid = dma_spec->args[0];
> + cpuid = dma_spec->args[1];
> + dma_spec->args_count = 1;
> +
> + if (devid > MAX_DMA_MAPPING_ID) {
> + dev_err(&pdev->dev, "invalid device id: %u\n", devid);
> + return ERR_PTR(-EINVAL);
> + }
> +
> + if (cpuid > MAX_DMA_CPU_ID) {
> + dev_err(&pdev->dev, "invalid cpu id: %u\n", cpuid);
> + return ERR_PTR(-EINVAL);
> + }
> +
> + dma_spec->np = of_parse_phandle(ofdma->of_node, "dma-masters", 0);
> + if (!dma_spec->np) {
> + dev_err(&pdev->dev, "can't get dma master\n");
> + return ERR_PTR(-EINVAL);
> + }
> +
> + spin_lock_irqsave(&dmamux->lock, flags);
> +
> + if (test_bit(devid, dmamux->mapped_peripherals)) {
> + llist_for_each_entry(map, dmamux->reserve_maps.first, node) {
> + if (map->peripheral == devid && map->cpu == cpuid)
> + goto found;
> + }
> +
> + ret = -EINVAL;
> + goto failed;
> + } else {
> + node = llist_del_first(&dmamux->free_maps);
> + if (!node) {
> + ret = -ENODEV;
> + goto failed;
> + }
> +
> + map = llist_entry(node, struct cv1800_dmamux_map, node);
> + llist_add(&map->node, &dmamux->reserve_maps);
> + set_bit(devid, dmamux->mapped_peripherals);
> + }
> +
> +found:
> + chid = map->channel;
> + map->peripheral = devid;
> + map->cpu = cpuid;
> +
> + regmap_set_bits(dmamux->regmap,
> + DMAMUX_CH_REG(chid),
> + DMAMUX_CH_SET(chid, devid));
> +
> + regmap_update_bits(dmamux->regmap, CV1800_SDMA_DMA_INT_MUX,
> + DMAMUX_INT_CH_MASK(chid, cpuid),
> + DMAMUX_INT_CH_BIT(chid, cpuid));
> +
> + spin_unlock_irqrestore(&dmamux->lock, flags);
> +
> + dma_spec->args[0] = chid;
> +
> + dev_dbg(&pdev->dev, "register channel %u for req %u (cpu %u)\n",
> + chid, devid, cpuid);
> +
> + return map;
> +
> +failed:
> + spin_unlock_irqrestore(&dmamux->lock, flags);
> + of_node_put(dma_spec->np);
> + dev_err(&pdev->dev, "errno %d\n", ret);
> + return ERR_PTR(ret);
> +}
> +
> +static int cv1800_dmamux_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *mux_node = dev->of_node;
> + struct cv1800_dmamux_data *data;
> + struct cv1800_dmamux_map *tmp;
> + struct device *parent = dev->parent;
> + struct regmap *regmap = NULL;
> + unsigned int i;
> +
> + if (!parent)
> + return -ENODEV;
> +
> + regmap = device_node_to_regmap(parent->of_node);
> + if (IS_ERR(regmap))
> + return PTR_ERR(regmap);
> +
> + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + spin_lock_init(&data->lock);
> + init_llist_head(&data->free_maps);
> + init_llist_head(&data->reserve_maps);
> +
> + for (i = 0; i <= MAX_DMA_CH_ID; i++) {
> + tmp = devm_kmalloc(dev, sizeof(*tmp), GFP_KERNEL);
> + if (!tmp) {
> + /* It is OK for not allocating all channel */
> + dev_warn(dev, "can not allocate channel %u\n", i);
> + continue;
> + }
> +
> + init_llist_node(&tmp->node);
> + tmp->channel = i;
> + llist_add(&tmp->node, &data->free_maps);
> + }
> +
> + /* if no channel is allocated, the probe must fail */
> + if (llist_empty(&data->free_maps))
> + return -ENOMEM;
> +
> + data->regmap = regmap;
> + data->dmarouter.dev = dev;
> + data->dmarouter.route_free = cv1800_dmamux_free;
> +
> + platform_set_drvdata(pdev, data);
> +
> + return of_dma_router_register(mux_node,
> + cv1800_dmamux_route_allocate,
> + &data->dmarouter);
> +}
> +
> +static void cv1800_dmamux_remove(struct platform_device *pdev)
> +{
> + of_dma_controller_free(pdev->dev.of_node);
> +}
> +
> +static const struct of_device_id cv1800_dmamux_ids[] = {
> + { .compatible = "sophgo,cv1800b-dmamux", },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, cv1800_dmamux_ids);
> +
> +static struct platform_driver cv1800_dmamux_driver = {
> + .driver = {
> + .name = "cv1800-dmamux",
> + .of_match_table = cv1800_dmamux_ids,
> + },
> + .probe = cv1800_dmamux_probe,
> + .remove_new = cv1800_dmamux_remove,
> +};
> +module_platform_driver(cv1800_dmamux_driver);
> +
> +MODULE_AUTHOR("Inochi Amaoto <inochiama@xxxxxxxxxxx>");
> +MODULE_DESCRIPTION("Sophgo CV1800/SG2000 Series SoC DMAMUX driver");
> +MODULE_LICENSE("GPL");
> --
> 2.46.0
--
~Vinod
