linux/drivers/dma/ti-dma-crossbar.c
Peter Ujfalusi 42dbdcc6bf dmaengine: ti-dma-crossbar: Add support for crossbar on AM33xx/AM43xx
The DMA event crossbar on AM33xx/AM43xx is different from the one found in
DRA7x family.
Instead of a single event crossbar it has 64 identical mux attached to each
eDMA event line. When the 0 event mux is selected, the default mapped event
is going to be routed to the corresponding eDMA event line. If different
mux is selected, then the selected event is going to be routed to the given
eDMA event.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2015-10-27 10:22:45 +09:00

401 lines
9.7 KiB
C

/*
* 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/idr.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 struct of_device_id ti_dma_xbar_match[] = {
{
.compatible = "ti,dra7-dma-crossbar",
.data = (void *)TI_XBAR_DRA7,
},
{
.compatible = "ti,am335x-edma-crossbar",
.data = (void *)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;
u16 mux_val;
};
static inline void ti_am335x_xbar_write(void __iomem *iomem, int event, u16 val)
{
writeb_relaxed(val & 0x1f, 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 = (u16)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");
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
#define TI_XBAR_EDMA_OFFSET 0
#define TI_XBAR_SDMA_OFFSET 1
struct ti_dra7_xbar_data {
void __iomem *iomem;
struct dma_router dmarouter;
struct idr map_idr;
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);
idr_remove(&xbar->map_idr, map->xbar_out);
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);
}
map->xbar_out = idr_alloc(&xbar->map_idr, NULL, 0, xbar->dma_requests,
GFP_KERNEL);
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;
}
static const struct of_device_id ti_dra7_master_match[] = {
{
.compatible = "ti,omap4430-sdma",
.data = (void *)TI_XBAR_SDMA_OFFSET,
},
{
.compatible = "ti,edma3",
.data = (void *)TI_XBAR_EDMA_OFFSET,
},
{},
};
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 resource *res;
u32 safe_val;
void __iomem *iomem;
int i, ret;
if (!node)
return -ENODEV;
xbar = devm_kzalloc(&pdev->dev, sizeof(*xbar), GFP_KERNEL);
if (!xbar)
return -ENOMEM;
idr_init(&xbar->map_idr);
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");
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);
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;
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;
platform_set_drvdata(pdev, xbar);
/* Reset the crossbar */
for (i = 0; i < xbar->dma_requests; i++)
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++)
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,
};
int omap_dmaxbar_init(void)
{
return platform_driver_register(&ti_dma_xbar_driver);
}
arch_initcall(omap_dmaxbar_init);