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Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma

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Pull second set of slave-dmaengine updates from Vinod Koul:
 "Arnd's patch moves the dw_dmac to use generic DMA binding.  I agreed
  to merge this late as it will avoid the conflicts between trees.

  The second patch from Matt adding a dma_request_slave_channel_compat
  API was supposed to be picked up, but somehow never got picked up.
  Some patches dependent on this are already in -next :("

* 'next' of git://git.infradead.org/users/vkoul/slave-dma:
  dmaengine: dw_dmac: move to generic DMA binding
  dmaengine: add dma_request_slave_channel_compat()
This commit is contained in:
Linus Torvalds 2013-03-03 10:20:22 -08:00
commit 527c680f7c
5 changed files with 128 additions and 117 deletions
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72
Documentation/devicetree/bindings/dma/snps-dma.txt
View File

@ -3,59 +3,61 @@
Required properties:
- compatible: "snps,dma-spear1340"
- reg: Address range of the DMAC registers
- interrupt-parent: Should be the phandle for the interrupt controller
that services interrupts for this device
- interrupt: Should contain the DMAC interrupt number
- nr_channels: Number of channels supported by hardware
- is_private: The device channels should be marked as private and not for by the
general purpose DMA channel allocator. False if not passed.
- dma-channels: Number of channels supported by hardware
- dma-requests: Number of DMA request lines supported, up to 16
- dma-masters: Number of AHB masters supported by the controller
- #dma-cells: must be <3>
- chan_allocation_order: order of allocation of channel, 0 (default): ascending,
1: descending
- chan_priority: priority of channels. 0 (default): increase from chan 0->n, 1:
increase from chan n->0
- block_size: Maximum block size supported by the controller
- nr_masters: Number of AHB masters supported by the controller
- data_width: Maximum data width supported by hardware per AHB master
(0 - 8bits, 1 - 16bits, ..., 5 - 256bits)
- slave_info:
- bus_id: name of this device channel, not just a device name since
devices may have more than one channel e.g. "foo_tx". For using the
dw_generic_filter(), slave drivers must pass exactly this string as
param to filter function.
- cfg_hi: Platform-specific initializer for the CFG_HI register
- cfg_lo: Platform-specific initializer for the CFG_LO register
- src_master: src master for transfers on allocated channel.
- dst_master: dest master for transfers on allocated channel.
Optional properties:
- interrupt-parent: Should be the phandle for the interrupt controller
that services interrupts for this device
- is_private: The device channels should be marked as private and not for by the
general purpose DMA channel allocator. False if not passed.
Example:
dma@fc000000 {
dmahost: dma@fc000000 {
compatible = "snps,dma-spear1340";
reg = <0xfc000000 0x1000>;
interrupt-parent = <&vic1>;
interrupts = <12>;
nr_channels = <8>;
dma-channels = <8>;
dma-requests = <16>;
dma-masters = <2>;
#dma-cells = <3>;
chan_allocation_order = <1>;
chan_priority = <1>;
block_size = <0xfff>;
nr_masters = <2>;
data_width = <3 3 0 0>;
slave_info {
uart0-tx {
bus_id = "uart0-tx";
cfg_hi = <0x4000>; /* 0x8 << 11 */
cfg_lo = <0>;
src_master = <0>;
dst_master = <1>;
};
spi0-tx {
bus_id = "spi0-tx";
cfg_hi = <0x2000>; /* 0x4 << 11 */
cfg_lo = <0>;
src_master = <0>;
dst_master = <0>;
};
};
};
DMA clients connected to the Designware DMA controller must use the format
described in the dma.txt file, using a four-cell specifier for each channel.
The four cells in order are:
1. A phandle pointing to the DMA controller
2. The DMA request line number
3. Source master for transfers on allocated channel
4. Destination master for transfers on allocated channel
Example:
serial@e0000000 {
compatible = "arm,pl011", "arm,primecell";
reg = <0xe0000000 0x1000>;
interrupts = <0 35 0x4>;
status = "disabled";
dmas = <&dmahost 12 0 1>,
<&dmahost 13 0 1 0>;
dma-names = "rx", "rx";
};

145
drivers/dma/dw_dmac.c
View File

@ -20,6 +20,7 @@
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_dma.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/platform_device.h>
@ -171,7 +172,13 @@ static void dwc_initialize(struct dw_dma_chan *dwc)
if (dwc->initialized == true)
return;
if (dws) {
if (dws && dws->cfg_hi == ~0 && dws->cfg_lo == ~0) {
/* autoconfigure based on request line from DT */
if (dwc->direction == DMA_MEM_TO_DEV)
cfghi = DWC_CFGH_DST_PER(dwc->request_line);
else if (dwc->direction == DMA_DEV_TO_MEM)
cfghi = DWC_CFGH_SRC_PER(dwc->request_line);
} else if (dws) {
/*
* We need controller-specific data to set up slave
* transfers.
@ -1226,49 +1233,64 @@ static void dwc_free_chan_resources(struct dma_chan *chan)
dev_vdbg(chan2dev(chan), "%s: done\n", __func__);
}
bool dw_dma_generic_filter(struct dma_chan *chan, void *param)
struct dw_dma_filter_args {
struct dw_dma *dw;
unsigned int req;
unsigned int src;
unsigned int dst;
};
static bool dw_dma_generic_filter(struct dma_chan *chan, void *param)
{
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
struct dw_dma *dw = to_dw_dma(chan->device);
static struct dw_dma *last_dw;
static char *last_bus_id;
int i = -1;
struct dw_dma_filter_args *fargs = param;
struct dw_dma_slave *dws = &dwc->slave;
/*
* dmaengine framework calls this routine for all channels of all dma
* controller, until true is returned. If 'param' bus_id is not
* registered with a dma controller (dw), then there is no need of
* running below function for all channels of dw.
*
* This block of code does this by saving the parameters of last
* failure. If dw and param are same, i.e. trying on same dw with
* different channel, return false.
*/
if ((last_dw == dw) && (last_bus_id == param))
return false;
/*
* Return true:
* - If dw_dma's platform data is not filled with slave info, then all
* dma controllers are fine for transfer.
* - Or if param is NULL
*/
if (!dw->sd || !param)
return true;
/* ensure the device matches our channel */
if (chan->device != &fargs->dw->dma)
return false;
while (++i < dw->sd_count) {
if (!strcmp(dw->sd[i].bus_id, param)) {
chan->private = &dw->sd[i];
last_dw = NULL;
last_bus_id = NULL;
dws->dma_dev = dw->dma.dev;
dws->cfg_hi = ~0;
dws->cfg_lo = ~0;
dws->src_master = fargs->src;
dws->dst_master = fargs->dst;
return true;
}
}
dwc->request_line = fargs->req;
last_dw = dw;
last_bus_id = param;
return false;
chan->private = dws;
return true;
}
static struct dma_chan *dw_dma_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma)
{
struct dw_dma *dw = ofdma->of_dma_data;
struct dw_dma_filter_args fargs = {
.dw = dw,
};
dma_cap_mask_t cap;
if (dma_spec->args_count != 3)
return NULL;
fargs.req = be32_to_cpup(dma_spec->args+0);
fargs.src = be32_to_cpup(dma_spec->args+1);
fargs.dst = be32_to_cpup(dma_spec->args+2);
if (WARN_ON(fargs.req >= DW_DMA_MAX_NR_REQUESTS ||
fargs.src >= dw->nr_masters ||
fargs.dst >= dw->nr_masters))
return NULL;
dma_cap_zero(cap);
dma_cap_set(DMA_SLAVE, cap);
/* TODO: there should be a simpler way to do this */
return dma_request_channel(cap, dw_dma_generic_filter, &fargs);
}
EXPORT_SYMBOL(dw_dma_generic_filter);
/* --------------------- Cyclic DMA API extensions -------------------- */
@ -1554,9 +1576,8 @@ static void dw_dma_off(struct dw_dma *dw)
static struct dw_dma_platform_data *
dw_dma_parse_dt(struct platform_device *pdev)
{
struct device_node *sn, *cn, *np = pdev->dev.of_node;
struct device_node *np = pdev->dev.of_node;
struct dw_dma_platform_data *pdata;
struct dw_dma_slave *sd;
u32 tmp, arr[4];
if (!np) {
@ -1568,7 +1589,7 @@ dw_dma_parse_dt(struct platform_device *pdev)
if (!pdata)
return NULL;
if (of_property_read_u32(np, "nr_channels", &pdata->nr_channels))
if (of_property_read_u32(np, "dma-channels", &pdata->nr_channels))
return NULL;
if (of_property_read_bool(np, "is_private"))
@ -1583,7 +1604,7 @@ dw_dma_parse_dt(struct platform_device *pdev)
if (!of_property_read_u32(np, "block_size", &tmp))
pdata->block_size = tmp;
if (!of_property_read_u32(np, "nr_masters", &tmp)) {
if (!of_property_read_u32(np, "dma-masters", &tmp)) {
if (tmp > 4)
return NULL;
@ -1595,36 +1616,6 @@ dw_dma_parse_dt(struct platform_device *pdev)
for (tmp = 0; tmp < pdata->nr_masters; tmp++)
pdata->data_width[tmp] = arr[tmp];
/* parse slave data */
sn = of_find_node_by_name(np, "slave_info");
if (!sn)
return pdata;
/* calculate number of slaves */
tmp = of_get_child_count(sn);
if (!tmp)
return NULL;
sd = devm_kzalloc(&pdev->dev, sizeof(*sd) * tmp, GFP_KERNEL);
if (!sd)
return NULL;
pdata->sd = sd;
pdata->sd_count = tmp;
for_each_child_of_node(sn, cn) {
sd->dma_dev = &pdev->dev;
of_property_read_string(cn, "bus_id", &sd->bus_id);
of_property_read_u32(cn, "cfg_hi", &sd->cfg_hi);
of_property_read_u32(cn, "cfg_lo", &sd->cfg_lo);
if (!of_property_read_u32(cn, "src_master", &tmp))
sd->src_master = tmp;
if (!of_property_read_u32(cn, "dst_master", &tmp))
sd->dst_master = tmp;
sd++;
}
return pdata;
}
#else
@ -1705,8 +1696,6 @@ static int dw_probe(struct platform_device *pdev)
clk_prepare_enable(dw->clk);
dw->regs = regs;
dw->sd = pdata->sd;
dw->sd_count = pdata->sd_count;
/* get hardware configuration parameters */
if (autocfg) {
@ -1837,6 +1826,14 @@ static int dw_probe(struct platform_device *pdev)
dma_async_device_register(&dw->dma);
if (pdev->dev.of_node) {
err = of_dma_controller_register(pdev->dev.of_node,
dw_dma_xlate, dw);
if (err && err != -ENODEV)
dev_err(&pdev->dev,
"could not register of_dma_controller\n");
}
return 0;
}
@ -1845,6 +1842,8 @@ static int dw_remove(struct platform_device *pdev)
struct dw_dma *dw = platform_get_drvdata(pdev);
struct dw_dma_chan *dwc, *_dwc;
if (pdev->dev.of_node)
of_dma_controller_free(pdev->dev.of_node);
dw_dma_off(dw);
dma_async_device_unregister(&dw->dma);

7
drivers/dma/dw_dmac_regs.h
View File

@ -13,6 +13,7 @@
#include <linux/dw_dmac.h>
#define DW_DMA_MAX_NR_CHANNELS 8
#define DW_DMA_MAX_NR_REQUESTS 16
/* flow controller */
enum dw_dma_fc {
@ -211,6 +212,8 @@ struct dw_dma_chan {
/* hardware configuration */
unsigned int block_size;
bool nollp;
unsigned int request_line;
struct dw_dma_slave slave;
/* configuration passed via DMA_SLAVE_CONFIG */
struct dma_slave_config dma_sconfig;
@ -239,10 +242,6 @@ struct dw_dma {
struct tasklet_struct tasklet;
struct clk *clk;
/* slave information */
struct dw_dma_slave *sd;
unsigned int sd_count;
u8 all_chan_mask;
/* hardware configuration */

16
include/linux/dmaengine.h
View File

@ -1001,6 +1001,22 @@ void dma_run_dependencies(struct dma_async_tx_descriptor *tx);
struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type);
struct dma_chan *net_dma_find_channel(void);
#define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y)
#define dma_request_slave_channel_compat(mask, x, y, dev, name) \
__dma_request_slave_channel_compat(&(mask), x, y, dev, name)
static inline struct dma_chan
*__dma_request_slave_channel_compat(dma_cap_mask_t *mask, dma_filter_fn fn,
void *fn_param, struct device *dev,
char *name)
{
struct dma_chan *chan;
chan = dma_request_slave_channel(dev, name);
if (chan)
return chan;
return __dma_request_channel(mask, fn, fn_param);
}
/* --- Helper iov-locking functions --- */

5
include/linux/dw_dmac.h
View File

@ -27,7 +27,6 @@
*/
struct dw_dma_slave {
struct device *dma_dev;
const char *bus_id;
u32 cfg_hi;
u32 cfg_lo;
u8 src_master;
@ -60,9 +59,6 @@ struct dw_dma_platform_data {
unsigned short block_size;
unsigned char nr_masters;
unsigned char data_width[4];
struct dw_dma_slave *sd;
unsigned int sd_count;
};
/* bursts size */
@ -114,6 +110,5 @@ void dw_dma_cyclic_stop(struct dma_chan *chan);
dma_addr_t dw_dma_get_src_addr(struct dma_chan *chan);
dma_addr_t dw_dma_get_dst_addr(struct dma_chan *chan);
bool dw_dma_generic_filter(struct dma_chan *chan, void *param);
#endif /* DW_DMAC_H */