diff options
Diffstat (limited to 'drivers/dma/ti/dma-crossbar.c')
| -rw-r--r-- | drivers/dma/ti/dma-crossbar.c | 478 |
1 files changed, 478 insertions, 0 deletions
diff --git a/drivers/dma/ti/dma-crossbar.c b/drivers/dma/ti/dma-crossbar.c new file mode 100644 index 000000000000..9272b173c746 --- /dev/null +++ b/drivers/dma/ti/dma-crossbar.c @@ -0,0 +1,478 @@ +/* + * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com + * Author: Peter Ujfalusi <peter.ujfalusi@ti.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/list.h> +#include <linux/io.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/of_dma.h> + +#define TI_XBAR_DRA7 0 +#define TI_XBAR_AM335X 1 +static const u32 ti_xbar_type[] = { + [TI_XBAR_DRA7] = TI_XBAR_DRA7, + [TI_XBAR_AM335X] = TI_XBAR_AM335X, +}; + +static const struct of_device_id ti_dma_xbar_match[] = { + { + .compatible = "ti,dra7-dma-crossbar", + .data = &ti_xbar_type[TI_XBAR_DRA7], + }, + { + .compatible = "ti,am335x-edma-crossbar", + .data = &ti_xbar_type[TI_XBAR_AM335X], + }, + {}, +}; + +/* Crossbar on AM335x/AM437x family */ +#define TI_AM335X_XBAR_LINES 64 + +struct ti_am335x_xbar_data { + void __iomem *iomem; + + struct dma_router dmarouter; + + u32 xbar_events; /* maximum number of events to select in xbar */ + u32 dma_requests; /* number of DMA requests on eDMA */ +}; + +struct ti_am335x_xbar_map { + u16 dma_line; + u8 mux_val; +}; + +static inline void ti_am335x_xbar_write(void __iomem *iomem, int event, u8 val) +{ + /* + * TPCC_EVT_MUX_60_63 register layout is different than the + * rest, in the sense, that event 63 is mapped to lowest byte + * and event 60 is mapped to highest, handle it separately. + */ + if (event >= 60 && event <= 63) + writeb_relaxed(val, iomem + (63 - event % 4)); + else + writeb_relaxed(val, iomem + event); +} + +static void ti_am335x_xbar_free(struct device *dev, void *route_data) +{ + struct ti_am335x_xbar_data *xbar = dev_get_drvdata(dev); + struct ti_am335x_xbar_map *map = route_data; + + dev_dbg(dev, "Unmapping XBAR event %u on channel %u\n", + map->mux_val, map->dma_line); + + ti_am335x_xbar_write(xbar->iomem, map->dma_line, 0); + kfree(map); +} + +static void *ti_am335x_xbar_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 ti_am335x_xbar_data *xbar = platform_get_drvdata(pdev); + struct ti_am335x_xbar_map *map; + + if (dma_spec->args_count != 3) + return ERR_PTR(-EINVAL); + + if (dma_spec->args[2] >= xbar->xbar_events) { + dev_err(&pdev->dev, "Invalid XBAR event number: %d\n", + dma_spec->args[2]); + return ERR_PTR(-EINVAL); + } + + if (dma_spec->args[0] >= xbar->dma_requests) { + dev_err(&pdev->dev, "Invalid DMA request line number: %d\n", + dma_spec->args[0]); + return ERR_PTR(-EINVAL); + } + + /* The of_node_put() will be done in the core for the node */ + 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); + } + + map = kzalloc(sizeof(*map), GFP_KERNEL); + if (!map) { + of_node_put(dma_spec->np); + return ERR_PTR(-ENOMEM); + } + + map->dma_line = (u16)dma_spec->args[0]; + map->mux_val = (u8)dma_spec->args[2]; + + dma_spec->args[2] = 0; + dma_spec->args_count = 2; + + dev_dbg(&pdev->dev, "Mapping XBAR event%u to DMA%u\n", + map->mux_val, map->dma_line); + + ti_am335x_xbar_write(xbar->iomem, map->dma_line, map->mux_val); + + return map; +} + +static const struct of_device_id ti_am335x_master_match[] = { + { .compatible = "ti,edma3-tpcc", }, + {}, +}; + +static int ti_am335x_xbar_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + const struct of_device_id *match; + struct device_node *dma_node; + struct ti_am335x_xbar_data *xbar; + struct resource *res; + void __iomem *iomem; + int i, ret; + + if (!node) + return -ENODEV; + + xbar = devm_kzalloc(&pdev->dev, sizeof(*xbar), GFP_KERNEL); + if (!xbar) + return -ENOMEM; + + dma_node = of_parse_phandle(node, "dma-masters", 0); + if (!dma_node) { + dev_err(&pdev->dev, "Can't get DMA master node\n"); + return -ENODEV; + } + + match = of_match_node(ti_am335x_master_match, dma_node); + if (!match) { + dev_err(&pdev->dev, "DMA master is not supported\n"); + of_node_put(dma_node); + return -EINVAL; + } + + if (of_property_read_u32(dma_node, "dma-requests", + &xbar->dma_requests)) { + dev_info(&pdev->dev, + "Missing XBAR output information, using %u.\n", + TI_AM335X_XBAR_LINES); + xbar->dma_requests = TI_AM335X_XBAR_LINES; + } + of_node_put(dma_node); + + if (of_property_read_u32(node, "dma-requests", &xbar->xbar_events)) { + dev_info(&pdev->dev, + "Missing XBAR input information, using %u.\n", + TI_AM335X_XBAR_LINES); + xbar->xbar_events = TI_AM335X_XBAR_LINES; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + iomem = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(iomem)) + return PTR_ERR(iomem); + + xbar->iomem = iomem; + + xbar->dmarouter.dev = &pdev->dev; + xbar->dmarouter.route_free = ti_am335x_xbar_free; + + platform_set_drvdata(pdev, xbar); + + /* Reset the crossbar */ + for (i = 0; i < xbar->dma_requests; i++) + ti_am335x_xbar_write(xbar->iomem, i, 0); + + ret = of_dma_router_register(node, ti_am335x_xbar_route_allocate, + &xbar->dmarouter); + + return ret; +} + +/* Crossbar on DRA7xx family */ +#define TI_DRA7_XBAR_OUTPUTS 127 +#define TI_DRA7_XBAR_INPUTS 256 + +struct ti_dra7_xbar_data { + void __iomem *iomem; + + struct dma_router dmarouter; + struct mutex mutex; + unsigned long *dma_inuse; + + u16 safe_val; /* Value to rest the crossbar lines */ + u32 xbar_requests; /* number of DMA requests connected to XBAR */ + u32 dma_requests; /* number of DMA requests forwarded to DMA */ + u32 dma_offset; +}; + +struct ti_dra7_xbar_map { + u16 xbar_in; + int xbar_out; +}; + +static inline void ti_dra7_xbar_write(void __iomem *iomem, int xbar, u16 val) +{ + writew_relaxed(val, iomem + (xbar * 2)); +} + +static void ti_dra7_xbar_free(struct device *dev, void *route_data) +{ + struct ti_dra7_xbar_data *xbar = dev_get_drvdata(dev); + struct ti_dra7_xbar_map *map = route_data; + + dev_dbg(dev, "Unmapping XBAR%u (was routed to %d)\n", + map->xbar_in, map->xbar_out); + + ti_dra7_xbar_write(xbar->iomem, map->xbar_out, xbar->safe_val); + mutex_lock(&xbar->mutex); + clear_bit(map->xbar_out, xbar->dma_inuse); + mutex_unlock(&xbar->mutex); + kfree(map); +} + +static void *ti_dra7_xbar_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 ti_dra7_xbar_data *xbar = platform_get_drvdata(pdev); + struct ti_dra7_xbar_map *map; + + if (dma_spec->args[0] >= xbar->xbar_requests) { + dev_err(&pdev->dev, "Invalid XBAR request number: %d\n", + dma_spec->args[0]); + return ERR_PTR(-EINVAL); + } + + /* The of_node_put() will be done in the core for the node */ + 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); + } + + map = kzalloc(sizeof(*map), GFP_KERNEL); + if (!map) { + of_node_put(dma_spec->np); + return ERR_PTR(-ENOMEM); + } + + mutex_lock(&xbar->mutex); + map->xbar_out = find_first_zero_bit(xbar->dma_inuse, + xbar->dma_requests); + if (map->xbar_out == xbar->dma_requests) { + mutex_unlock(&xbar->mutex); + dev_err(&pdev->dev, "Run out of free DMA requests\n"); + kfree(map); + return ERR_PTR(-ENOMEM); + } + set_bit(map->xbar_out, xbar->dma_inuse); + mutex_unlock(&xbar->mutex); + + map->xbar_in = (u16)dma_spec->args[0]; + + dma_spec->args[0] = map->xbar_out + xbar->dma_offset; + + dev_dbg(&pdev->dev, "Mapping XBAR%u to DMA%d\n", + map->xbar_in, map->xbar_out); + + ti_dra7_xbar_write(xbar->iomem, map->xbar_out, map->xbar_in); + + return map; +} + +#define TI_XBAR_EDMA_OFFSET 0 +#define TI_XBAR_SDMA_OFFSET 1 +static const u32 ti_dma_offset[] = { + [TI_XBAR_EDMA_OFFSET] = 0, + [TI_XBAR_SDMA_OFFSET] = 1, +}; + +static const struct of_device_id ti_dra7_master_match[] = { + { + .compatible = "ti,omap4430-sdma", + .data = &ti_dma_offset[TI_XBAR_SDMA_OFFSET], + }, + { + .compatible = "ti,edma3", + .data = &ti_dma_offset[TI_XBAR_EDMA_OFFSET], + }, + { + .compatible = "ti,edma3-tpcc", + .data = &ti_dma_offset[TI_XBAR_EDMA_OFFSET], + }, + {}, +}; + +static inline void ti_dra7_xbar_reserve(int offset, int len, unsigned long *p) +{ + for (; len > 0; len--) + set_bit(offset + (len - 1), p); +} + +static int ti_dra7_xbar_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + const struct of_device_id *match; + struct device_node *dma_node; + struct ti_dra7_xbar_data *xbar; + struct property *prop; + struct resource *res; + u32 safe_val; + int sz; + void __iomem *iomem; + int i, ret; + + if (!node) + return -ENODEV; + + xbar = devm_kzalloc(&pdev->dev, sizeof(*xbar), GFP_KERNEL); + if (!xbar) + return -ENOMEM; + + dma_node = of_parse_phandle(node, "dma-masters", 0); + if (!dma_node) { + dev_err(&pdev->dev, "Can't get DMA master node\n"); + return -ENODEV; + } + + match = of_match_node(ti_dra7_master_match, dma_node); + if (!match) { + dev_err(&pdev->dev, "DMA master is not supported\n"); + of_node_put(dma_node); + return -EINVAL; + } + + if (of_property_read_u32(dma_node, "dma-requests", + &xbar->dma_requests)) { + dev_info(&pdev->dev, + "Missing XBAR output information, using %u.\n", + TI_DRA7_XBAR_OUTPUTS); + xbar->dma_requests = TI_DRA7_XBAR_OUTPUTS; + } + of_node_put(dma_node); + + xbar->dma_inuse = devm_kcalloc(&pdev->dev, + BITS_TO_LONGS(xbar->dma_requests), + sizeof(unsigned long), GFP_KERNEL); + if (!xbar->dma_inuse) + return -ENOMEM; + + if (of_property_read_u32(node, "dma-requests", &xbar->xbar_requests)) { + dev_info(&pdev->dev, + "Missing XBAR input information, using %u.\n", + TI_DRA7_XBAR_INPUTS); + xbar->xbar_requests = TI_DRA7_XBAR_INPUTS; + } + + if (!of_property_read_u32(node, "ti,dma-safe-map", &safe_val)) + xbar->safe_val = (u16)safe_val; + + + prop = of_find_property(node, "ti,reserved-dma-request-ranges", &sz); + if (prop) { + const char pname[] = "ti,reserved-dma-request-ranges"; + u32 (*rsv_events)[2]; + size_t nelm = sz / sizeof(*rsv_events); + int i; + + if (!nelm) + return -EINVAL; + + rsv_events = kcalloc(nelm, sizeof(*rsv_events), GFP_KERNEL); + if (!rsv_events) + return -ENOMEM; + + ret = of_property_read_u32_array(node, pname, (u32 *)rsv_events, + nelm * 2); + if (ret) + return ret; + + for (i = 0; i < nelm; i++) { + ti_dra7_xbar_reserve(rsv_events[i][0], rsv_events[i][1], + xbar->dma_inuse); + } + kfree(rsv_events); + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + iomem = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(iomem)) + return PTR_ERR(iomem); + + xbar->iomem = iomem; + + xbar->dmarouter.dev = &pdev->dev; + xbar->dmarouter.route_free = ti_dra7_xbar_free; + xbar->dma_offset = *(u32 *)match->data; + + mutex_init(&xbar->mutex); + platform_set_drvdata(pdev, xbar); + + /* Reset the crossbar */ + for (i = 0; i < xbar->dma_requests; i++) { + if (!test_bit(i, xbar->dma_inuse)) + ti_dra7_xbar_write(xbar->iomem, i, xbar->safe_val); + } + + ret = of_dma_router_register(node, ti_dra7_xbar_route_allocate, + &xbar->dmarouter); + if (ret) { + /* Restore the defaults for the crossbar */ + for (i = 0; i < xbar->dma_requests; i++) { + if (!test_bit(i, xbar->dma_inuse)) + ti_dra7_xbar_write(xbar->iomem, i, i); + } + } + + return ret; +} + +static int ti_dma_xbar_probe(struct platform_device *pdev) +{ + const struct of_device_id *match; + int ret; + + match = of_match_node(ti_dma_xbar_match, pdev->dev.of_node); + if (unlikely(!match)) + return -EINVAL; + + switch (*(u32 *)match->data) { + case TI_XBAR_DRA7: + ret = ti_dra7_xbar_probe(pdev); + break; + case TI_XBAR_AM335X: + ret = ti_am335x_xbar_probe(pdev); + break; + default: + dev_err(&pdev->dev, "Unsupported crossbar\n"); + ret = -ENODEV; + break; + } + + return ret; +} + +static struct platform_driver ti_dma_xbar_driver = { + .driver = { + .name = "ti-dma-crossbar", + .of_match_table = of_match_ptr(ti_dma_xbar_match), + }, + .probe = ti_dma_xbar_probe, +}; + +static int omap_dmaxbar_init(void) +{ + return platform_driver_register(&ti_dma_xbar_driver); +} +arch_initcall(omap_dmaxbar_init); |