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ARM: at91/tc: add device tree support to atmel_tclib
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Device tree support added to atmel_tclib: the generic Timer Counter
library. This is used by the clocksource/clockevent driver tcb_clksrc.

The current DT enabled platforms are also modified to use it:
- .dtsi files are modified to add Timer Counter Block entries
- alias are created to allow identification of each block
- clkdev lookup tables are added for clocks identification.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
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Nicolas Ferre committed Mar 1, 2012
1 parent 2983129 commit 3a61a5d
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Showing 8 changed files with 122 additions and 2 deletions.
24 changes: 24 additions & 0 deletions Documentation/devicetree/bindings/arm/atmel-at91.txt
Original file line number Diff line number Diff line change
Expand Up @@ -6,3 +6,27 @@ PIT Timer required properties:
- reg: Should contain registers location and length
- interrupts: Should contain interrupt for the PIT which is the IRQ line
shared across all System Controller members.

TC/TCLIB Timer required properties:
- compatible: Should be "atmel,<chip>-pit".
<chip> can be "at91rm9200" or "at91sam9x5"
- reg: Should contain registers location and length
- interrupts: Should contain all interrupts for the TC block
Note that you can specify several interrupt cells if the TC
block has one interrupt per channel.

Examples:

One interrupt per TC block:
tcb0: timer@fff7c000 {
compatible = "atmel,at91rm9200-tcb";
reg = <0xfff7c000 0x100>;
interrupts = <18 4>;
};

One interrupt per TC channel in a TC block:
tcb1: timer@fffdc000 {
compatible = "atmel,at91rm9200-tcb";
reg = <0xfffdc000 0x100>;
interrupts = <26 4 27 4 28 4>;
};
14 changes: 14 additions & 0 deletions arch/arm/boot/dts/at91sam9g20.dtsi
Original file line number Diff line number Diff line change
Expand Up @@ -26,6 +26,8 @@
gpio0 = &pioA;
gpio1 = &pioB;
gpio2 = &pioC;
tcb0 = &tcb0;
tcb1 = &tcb1;
};
cpus {
cpu@0 {
Expand Down Expand Up @@ -63,6 +65,18 @@
interrupts = <1 4>;
};

tcb0: timer@fffa0000 {
compatible = "atmel,at91rm9200-tcb";
reg = <0xfffa0000 0x100>;
interrupts = <17 4 18 4 19 4>;
};

tcb1: timer@fffdc000 {
compatible = "atmel,at91rm9200-tcb";
reg = <0xfffdc000 0x100>;
interrupts = <26 4 27 4 28 4>;
};

pioA: gpio@fffff400 {
compatible = "atmel,at91rm9200-gpio";
reg = <0xfffff400 0x100>;
Expand Down
15 changes: 15 additions & 0 deletions arch/arm/boot/dts/at91sam9g45.dtsi
Original file line number Diff line number Diff line change
Expand Up @@ -27,6 +27,8 @@
gpio2 = &pioC;
gpio3 = &pioD;
gpio4 = &pioE;
tcb0 = &tcb0;
tcb1 = &tcb1;
};
cpus {
cpu@0 {
Expand Down Expand Up @@ -64,6 +66,19 @@
interrupts = <1 4>;
};


tcb0: timer@fff7c000 {
compatible = "atmel,at91rm9200-tcb";
reg = <0xfff7c000 0x100>;
interrupts = <18 4>;
};

tcb1: timer@fffd4000 {
compatible = "atmel,at91rm9200-tcb";
reg = <0xfffd4000 0x100>;
interrupts = <18 4>;
};

dma: dma-controller@ffffec00 {
compatible = "atmel,at91sam9g45-dma";
reg = <0xffffec00 0x200>;
Expand Down
7 changes: 7 additions & 0 deletions arch/arm/mach-at91/at91sam9260.c
Original file line number Diff line number Diff line change
Expand Up @@ -209,6 +209,13 @@ static struct clk_lookup periph_clocks_lookups[] = {
CLKDEV_CON_DEV_ID("usart", "fffd0000.serial", &usart3_clk),
CLKDEV_CON_DEV_ID("usart", "fffd4000.serial", &usart4_clk),
CLKDEV_CON_DEV_ID("usart", "fffd8000.serial", &usart5_clk),
/* more tc lookup table for DT entries */
CLKDEV_CON_DEV_ID("t0_clk", "fffa0000.timer", &tc0_clk),
CLKDEV_CON_DEV_ID("t1_clk", "fffa0000.timer", &tc1_clk),
CLKDEV_CON_DEV_ID("t2_clk", "fffa0000.timer", &tc2_clk),
CLKDEV_CON_DEV_ID("t0_clk", "fffdc000.timer", &tc3_clk),
CLKDEV_CON_DEV_ID("t1_clk", "fffdc000.timer", &tc4_clk),
CLKDEV_CON_DEV_ID("t2_clk", "fffdc000.timer", &tc5_clk),
/* fake hclk clock */
CLKDEV_CON_DEV_ID("hclk", "at91_ohci", &ohci_clk),
CLKDEV_CON_ID("pioA", &pioA_clk),
Expand Down
17 changes: 17 additions & 0 deletions arch/arm/mach-at91/at91sam9260_devices.c
Original file line number Diff line number Diff line change
Expand Up @@ -699,8 +699,25 @@ static struct platform_device at91sam9260_tcb1_device = {
.num_resources = ARRAY_SIZE(tcb1_resources),
};

#if defined(CONFIG_OF)
static struct of_device_id tcb_ids[] = {
{ .compatible = "atmel,at91rm9200-tcb" },
{ /*sentinel*/ }
};
#endif

static void __init at91_add_device_tc(void)
{
#if defined(CONFIG_OF)
struct device_node *np;

np = of_find_matching_node(NULL, tcb_ids);
if (np) {
of_node_put(np);
return;
}
#endif

platform_device_register(&at91sam9260_tcb0_device);
platform_device_register(&at91sam9260_tcb1_device);
}
Expand Down
3 changes: 3 additions & 0 deletions arch/arm/mach-at91/at91sam9g45.c
Original file line number Diff line number Diff line change
Expand Up @@ -229,6 +229,9 @@ static struct clk_lookup periph_clocks_lookups[] = {
CLKDEV_CON_DEV_ID("usart", "fff90000.serial", &usart1_clk),
CLKDEV_CON_DEV_ID("usart", "fff94000.serial", &usart2_clk),
CLKDEV_CON_DEV_ID("usart", "fff98000.serial", &usart3_clk),
/* more tc lookup table for DT entries */
CLKDEV_CON_DEV_ID("t0_clk", "fff7c000.timer", &tcb0_clk),
CLKDEV_CON_DEV_ID("t0_clk", "fffd4000.timer", &tcb0_clk),
/* fake hclk clock */
CLKDEV_CON_DEV_ID("hclk", "at91_ohci", &uhphs_clk),
CLKDEV_CON_ID("pioA", &pioA_clk),
Expand Down
17 changes: 17 additions & 0 deletions arch/arm/mach-at91/at91sam9g45_devices.c
Original file line number Diff line number Diff line change
Expand Up @@ -1090,8 +1090,25 @@ static struct platform_device at91sam9g45_tcb1_device = {
.num_resources = ARRAY_SIZE(tcb1_resources),
};

#if defined(CONFIG_OF)
static struct of_device_id tcb_ids[] = {
{ .compatible = "atmel,at91rm9200-tcb" },
{ /*sentinel*/ }
};
#endif

static void __init at91_add_device_tc(void)
{
#if defined(CONFIG_OF)
struct device_node *np;

np = of_find_matching_node(NULL, tcb_ids);
if (np) {
of_node_put(np);
return;
}
#endif

platform_device_register(&at91sam9g45_tcb0_device);
platform_device_register(&at91sam9g45_tcb1_device);
}
Expand Down
27 changes: 25 additions & 2 deletions drivers/misc/atmel_tclib.c
Original file line number Diff line number Diff line change
Expand Up @@ -6,8 +6,10 @@
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <linux/of.h>

/*
* This is a thin library to solve the problem of how to portably allocate
Expand Down Expand Up @@ -48,7 +50,13 @@ struct atmel_tc *atmel_tc_alloc(unsigned block, const char *name)

spin_lock(&tc_list_lock);
list_for_each_entry(tc, &tc_list, node) {
if (tc->pdev->id == block) {
if (tc->pdev->dev.of_node) {
if (of_alias_get_id(tc->pdev->dev.of_node, "tcb")
== block) {
pdev = tc->pdev;
break;
}
} else if (tc->pdev->id == block) {
pdev = tc->pdev;
break;
}
Expand Down Expand Up @@ -105,6 +113,18 @@ void atmel_tc_free(struct atmel_tc *tc)
}
EXPORT_SYMBOL_GPL(atmel_tc_free);

#if defined(CONFIG_OF)
static const struct of_device_id atmel_tcb_dt_ids[] = {
{
.compatible = "atmel,at91rm9200-tcb",
}, {
/* sentinel */
}
};

MODULE_DEVICE_TABLE(of, atmel_tcb_dt_ids);
#endif

static int __init tc_probe(struct platform_device *pdev)
{
struct atmel_tc *tc;
Expand Down Expand Up @@ -154,7 +174,10 @@ static int __init tc_probe(struct platform_device *pdev)
}

static struct platform_driver tc_driver = {
.driver.name = "atmel_tcb",
.driver = {
.name = "atmel_tcb",
.of_match_table = of_match_ptr(atmel_tcb_dt_ids),
},
};

static int __init tc_init(void)
Expand Down

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