To increase the number of peripheral requests, the FDMA crossbar can multiplex up to 96 peripheral requests to one of 3 fdma controllers.
Signed-off-by: Ludovic Barre <[email protected]> Signed-off-by: Peter Griffin <[email protected]> --- drivers/dma/Kconfig | 11 ++++ drivers/dma/Makefile | 1 + drivers/dma/st_fdma.c | 25 +++++++- drivers/dma/st_fdma.h | 32 ++++++++++ drivers/dma/st_fdma_xbar.c | 149 +++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 216 insertions(+), 2 deletions(-) create mode 100644 drivers/dma/st_fdma_xbar.c diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index 7a016e0..21802b1 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -522,4 +522,15 @@ config ST_FDMA Say Y here if you have such a chipset. If unsure, say N. +config ST_FDMA_XBAR + bool "ST FDMA crossbar" + depends on ST_FDMA + default y + help + Enable support for ST FDMA crossbar. + xbar add flexibility and increase the number of peripheral request + can be used by fdma xbar can multiplex until 96 peripheral requests + to one of 3 fdma controller + + endif diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index f68e6d8..19f18b1 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -50,6 +50,7 @@ obj-$(CONFIG_MOXART_DMA) += moxart-dma.o obj-$(CONFIG_FSL_RAID) += fsl_raid.o obj-$(CONFIG_FSL_EDMA) += fsl-edma.o obj-$(CONFIG_QCOM_BAM_DMA) += qcom_bam_dma.o +obj-$(CONFIG_ST_FDMA_XBAR) += st_fdma_xbar.o obj-$(CONFIG_ST_FDMA) += st_fdma.o obj-y += xilinx/ obj-$(CONFIG_INTEL_MIC_X100_DMA) += mic_x100_dma.o diff --git a/drivers/dma/st_fdma.c b/drivers/dma/st_fdma.c index 07a6df1..a870902 100644 --- a/drivers/dma/st_fdma.c +++ b/drivers/dma/st_fdma.c @@ -336,7 +336,9 @@ static int st_fdma_dreq_get(struct st_fdma_chan *fchan) return -EINVAL; } - if (try || req_line_cfg >= ST_FDMA_NR_DREQS) { + if (fdev->xbar_dev) + dreq_line = ffz(fdev->dreq_mask); + else if (try || req_line_cfg >= ST_FDMA_NR_DREQS) { dev_err(fdev->dev, "Invalid or used req line\n"); return -EINVAL; } else { @@ -903,6 +905,15 @@ static int st_fdma_slave_config(struct dma_chan *chan, else return -EINVAL; + if (fdev->xbar_dev) { + if (st_fdma_xbar_mux(fdev->xbar_dev, fchan->cfg.req_line, + fchan->dreq_line)) { + dev_err(fdev->dev, "Error routing req line\n"); + clear_bit(fchan->dreq_line, &fdev->dreq_mask); + return -EINVAL; + } + } + fchan->cfg.req_ctrl |= REQ_CTRL_NUM_OPS(maxburst-1); dreq_write(fchan, fchan->cfg.req_ctrl, REQ_CTRL); @@ -1044,6 +1055,13 @@ static int st_fdma_probe(struct platform_device *pdev) if (ret) goto err_clk; + fdev->xbar_dev = st_fdma_xbar_request(&pdev->dev); + if (IS_ERR(fdev->xbar_dev)) { + dev_err(&pdev->dev, "Failed to request xbar:%ld\n", + PTR_ERR(fdev->xbar_dev)); + goto err_clk; + } + /* Initialise the FDMA dreq (reserve 0 & 31 for FDMA use) */ fdev->dreq_mask = BIT(0) | BIT(31); @@ -1081,7 +1099,10 @@ static int st_fdma_probe(struct platform_device *pdev) goto err_dma_dev; } - dev_info(&pdev->dev, "ST FDMA engine driver, irq:%d\n", irq); + dev_info(&pdev->dev, "ST FDMA engine driver, irq:%d xbar(%s, id:%d)\n", + irq, fdev->xbar_dev ? + dev_name(&fdev->xbar_dev->pdev->dev) : "no", + fdev->xbar_dev ? fdev->xbar_dev->fdma_id : 0); return 0; diff --git a/drivers/dma/st_fdma.h b/drivers/dma/st_fdma.h index 533c811..dd46780 100644 --- a/drivers/dma/st_fdma.h +++ b/drivers/dma/st_fdma.h @@ -17,6 +17,20 @@ #define ST_FDMA_NR_DREQS 32 #define EM_SLIM 102 /* No official SLIM ELF ID */ +struct st_fdma_xbar { + void __iomem *io_base; + struct clk *clk; + u32 nr_requests; + u32 max_nr_requests; +}; + +struct st_fdma_xbar_dev { + struct platform_device *pdev; + struct st_fdma_xbar *xbar; + struct device *fdev; + u32 fdma_id; +}; + enum { CLK_SLIM, CLK_HI, @@ -135,6 +149,7 @@ struct st_fdma_dev { struct st_fdma_chan *chans; + struct st_fdma_xbar_dev *xbar_dev; spinlock_t dreq_lock; unsigned long dreq_mask; @@ -142,6 +157,23 @@ struct st_fdma_dev { atomic_t fw_loaded; }; +#if defined(CONFIG_ST_FDMA_XBAR) +struct st_fdma_xbar_dev *st_fdma_xbar_request(struct device *device); +int st_fdma_xbar_mux(struct st_fdma_xbar_dev *xbar_dev, + u32 in_dreq, u32 fdma_dreq); +#else +struct st_fdma_xbar_dev *st_fdma_xbar_request(struct device *device) +{ + return NULL; +} + +int st_fdma_xbar_mux(struct st_fdma_xbar_dev *xbar_dev, + u32 in_dreq, u32 fdma_dreq) +{ + return -ENODEV; +} +#endif + /* Registers*/ /* FDMA interface */ #define FDMA_ID_OFST 0x00000 diff --git a/drivers/dma/st_fdma_xbar.c b/drivers/dma/st_fdma_xbar.c new file mode 100644 index 0000000..c3b8e0f --- /dev/null +++ b/drivers/dma/st_fdma_xbar.c @@ -0,0 +1,149 @@ +/* + * st_fdma_xbar.c + * + * Copyright (C) 2014 STMicroelectronics + * Author: Ludovic Barre <[email protected]> + * License terms: GNU General Public License (GPL), version 2 + */ +#include <linux/init.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> + +#include "st_fdma.h" + +#define XBAR_1_0_MAX_REQ 96 + +int st_fdma_xbar_mux(struct st_fdma_xbar_dev *xbar_dev, + u32 per_req, u32 fdma_req) +{ + u32 out_req; + + if (per_req >= xbar_dev->xbar->nr_requests) + return -EINVAL; + + out_req = (xbar_dev->fdma_id * ST_FDMA_NR_DREQS) + fdma_req; + writel(per_req, xbar_dev->xbar->io_base + (out_req << 2)); + + dev_dbg(&xbar_dev->pdev->dev, "in_req:%d out_req:%d\n", + per_req, out_req); + + return 0; +} + +struct st_fdma_xbar_dev *st_fdma_xbar_request(struct device *device) +{ + struct device_node *np = device->of_node; + struct st_fdma_xbar_dev *xbar_dev; + struct of_phandle_args args; + int err; + + err = of_parse_phandle_with_args(np, "st,fdma-xbar", + "#st,fdma-xbar-cells", 0, &args); + if (err) + return NULL; + + xbar_dev = kzalloc(sizeof(*xbar_dev), GFP_KERNEL); + if (!xbar_dev) { + of_node_put(args.np); + err = -ENOMEM; + goto out; + } + + xbar_dev->pdev = of_find_device_by_node(args.np); + if (!xbar_dev->pdev) { + of_node_put(args.np); + err = -ENODEV; + goto free; + } + + of_node_put(args.np); + + xbar_dev->xbar = platform_get_drvdata(xbar_dev->pdev); + if (!xbar_dev->xbar) { + err = -EPROBE_DEFER; + goto pdev_put; + } + + xbar_dev->fdma_id = args.args[0]; + xbar_dev->fdev = device; + + return xbar_dev; + +pdev_put: + platform_device_put(xbar_dev->pdev); +free: + kfree(xbar_dev); +out: + return ERR_PTR(err); +} + +void st_fdma_xbar_free(struct st_fdma_xbar_dev *device) +{ + platform_device_put(device->pdev); + kfree(device); +} + +static const struct of_device_id st_fdma_xbar_match[] = { + { .compatible = "st,fdma-xbar-1.0", .data = (void *)XBAR_1_0_MAX_REQ }, + {}, +}; +MODULE_DEVICE_TABLE(of, st_fdma_xbar_match); + +static int st_fdma_xbar_probe(struct platform_device *pdev) +{ + const struct of_device_id *match; + struct device_node *np = pdev->dev.of_node; + struct st_fdma_xbar *xbar; + struct resource *res; + + match = of_match_device((st_fdma_xbar_match), &pdev->dev); + if (!match) { + dev_err(&pdev->dev, "No device match found\n"); + return -ENODEV; + } + + xbar = devm_kzalloc(&pdev->dev, sizeof(*xbar), GFP_KERNEL); + if (!xbar) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + xbar->io_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(xbar->io_base)) + return PTR_ERR(xbar->io_base); + + xbar->max_nr_requests = (unsigned long)match->data; + + if (of_property_read_u32(np, "dma-requests", &xbar->nr_requests)) + xbar->nr_requests = xbar->max_nr_requests; + + if (xbar->nr_requests > xbar->max_nr_requests) { + dev_err(&pdev->dev, "Nr requests not supported\n"); + return -EINVAL; + } + + platform_set_drvdata(pdev, xbar); + + return 0; +} + +static int st_fdma_xbar_remove(struct platform_device *pdev) +{ + return 0; +} + +static struct platform_driver st_fdma_xbar_driver = { + .driver = { + .name = "st-fdma-xbar", + .of_match_table = st_fdma_xbar_match, + }, + .probe = st_fdma_xbar_probe, + .remove = st_fdma_xbar_remove, +}; +module_platform_driver(st_fdma_xbar_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("STMicroelectronics FDMA cross bar"); +MODULE_AUTHOR("Ludovic.barre <[email protected]>"); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
