Introduce ARM AMBA bus
This will allow to detect the amba device and use the right driver for it at runtime. The code is base on linux 3.5. Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
This commit is contained in:
parent
298d15571d
commit
7492e86329
|
@ -1,4 +1,5 @@
|
|||
obj-y += base/
|
||||
obj-$(CONFIG_ARM_AMBA) += amba/
|
||||
obj-y += net/
|
||||
obj-y += serial/
|
||||
obj-y += mtd/
|
||||
|
|
|
@ -0,0 +1,2 @@
|
|||
|
||||
obj-y += bus.o
|
|
@ -0,0 +1,210 @@
|
|||
/*
|
||||
* Copyright (C) 2003 Deep Blue Solutions Ltd, All Rights Reserved.
|
||||
* Copyright (c) 2012 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
|
||||
*
|
||||
* Under GPLv2.
|
||||
*/
|
||||
#include <common.h>
|
||||
#include <driver.h>
|
||||
#include <linux/clk.h>
|
||||
#include <linux/amba/bus.h>
|
||||
#include <io.h>
|
||||
|
||||
#define to_amba_driver(d) container_of(d, struct amba_driver, drv)
|
||||
|
||||
static const struct amba_id *
|
||||
amba_lookup(const struct amba_id *table, struct amba_device *dev)
|
||||
{
|
||||
int ret = 0;
|
||||
|
||||
while (table->mask) {
|
||||
ret = (dev->periphid & table->mask) == table->id;
|
||||
if (ret)
|
||||
break;
|
||||
table++;
|
||||
}
|
||||
|
||||
return ret ? table : NULL;
|
||||
}
|
||||
|
||||
static int amba_match(struct device_d *dev, struct driver_d *drv)
|
||||
{
|
||||
struct amba_device *pcdev = to_amba_device(dev);
|
||||
|
||||
struct amba_driver *pcdrv = to_amba_driver(drv);
|
||||
|
||||
return amba_lookup(pcdrv->id_table, pcdev) == NULL;
|
||||
}
|
||||
|
||||
static int amba_get_enable_pclk(struct amba_device *pcdev)
|
||||
{
|
||||
struct clk *pclk = clk_get(&pcdev->dev, "apb_pclk");
|
||||
int ret;
|
||||
|
||||
pcdev->pclk = pclk;
|
||||
|
||||
if (IS_ERR(pclk))
|
||||
return PTR_ERR(pclk);
|
||||
|
||||
ret = clk_enable(pclk);
|
||||
if (ret) {
|
||||
clk_put(pclk);
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int amba_probe(struct device_d *dev)
|
||||
{
|
||||
struct amba_device *pcdev = to_amba_device(dev);
|
||||
struct amba_driver *pcdrv = to_amba_driver(dev->driver);
|
||||
const struct amba_id *id = amba_lookup(pcdrv->id_table, pcdev);
|
||||
|
||||
return pcdrv->probe(pcdev, id);
|
||||
}
|
||||
|
||||
static void amba_remove(struct device_d *dev)
|
||||
{
|
||||
struct amba_device *pcdev = to_amba_device(dev);
|
||||
struct amba_driver *drv = to_amba_driver(dev->driver);
|
||||
|
||||
drv->remove(pcdev);
|
||||
}
|
||||
|
||||
struct bus_type amba_bustype = {
|
||||
.name = "amba",
|
||||
.match = amba_match,
|
||||
.probe = amba_probe,
|
||||
.remove = amba_remove,
|
||||
};
|
||||
|
||||
int amba_driver_register(struct amba_driver *drv)
|
||||
{
|
||||
drv->drv.bus = &amba_bustype;
|
||||
|
||||
if (drv->probe)
|
||||
drv->drv.probe = amba_probe;
|
||||
if (drv->remove)
|
||||
drv->drv.remove = amba_remove;
|
||||
|
||||
return register_driver(&drv->drv);
|
||||
}
|
||||
|
||||
/**
|
||||
* amba_device_add - add a previously allocated AMBA device structure
|
||||
* @dev: AMBA device allocated by amba_device_alloc
|
||||
* @parent: resource parent for this devices resources
|
||||
*
|
||||
* Claim the resource, and read the device cell ID if not already
|
||||
* initialized. Register the AMBA device with the Linux device
|
||||
* manager.
|
||||
*/
|
||||
int amba_device_add(struct amba_device *dev)
|
||||
{
|
||||
u32 size;
|
||||
void __iomem *tmp;
|
||||
int i, ret;
|
||||
struct resource *res = NULL;
|
||||
|
||||
dev->dev.bus = &amba_bustype;
|
||||
|
||||
/*
|
||||
* Dynamically calculate the size of the resource
|
||||
* and use this for iomap
|
||||
*/
|
||||
size = resource_size(&dev->res);
|
||||
res = request_iomem_region("amba", dev->res.start, dev->res.end);
|
||||
if (!res)
|
||||
return -ENOMEM;
|
||||
dev->base = tmp = (void __force __iomem *)res->start;
|
||||
if (!tmp) {
|
||||
ret = -ENOMEM;
|
||||
goto err_release;
|
||||
}
|
||||
|
||||
/* Hard-coded primecell ID instead of plug-n-play */
|
||||
if (dev->periphid != 0)
|
||||
goto skip_probe;
|
||||
|
||||
ret = amba_get_enable_pclk(dev);
|
||||
if (ret == 0) {
|
||||
u32 pid, cid;
|
||||
|
||||
/*
|
||||
* Read pid and cid based on size of resource
|
||||
* they are located at end of region
|
||||
*/
|
||||
for (pid = 0, i = 0; i < 4; i++)
|
||||
pid |= (readl(tmp + size - 0x20 + 4 * i) & 255) <<
|
||||
(i * 8);
|
||||
for (cid = 0, i = 0; i < 4; i++)
|
||||
cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) <<
|
||||
(i * 8);
|
||||
|
||||
if (cid == AMBA_CID)
|
||||
dev->periphid = pid;
|
||||
|
||||
if (!dev->periphid)
|
||||
ret = -ENODEV;
|
||||
}
|
||||
|
||||
if (ret)
|
||||
goto err_release;
|
||||
|
||||
skip_probe:
|
||||
ret = register_device(&dev->dev);
|
||||
if (ret)
|
||||
goto err_release;
|
||||
|
||||
return ret;
|
||||
err_release:
|
||||
release_region(res);
|
||||
return ret;
|
||||
}
|
||||
|
||||
struct amba_device *
|
||||
amba_aphb_device_add(struct device_d *parent, const char *name, int id,
|
||||
resource_size_t base, size_t size,
|
||||
void *pdata, unsigned int periphid)
|
||||
{
|
||||
struct amba_device *dev;
|
||||
int ret;
|
||||
|
||||
dev = amba_device_alloc(name, id, base, size);
|
||||
|
||||
dev->periphid = periphid;
|
||||
dev->dev.platform_data = pdata;
|
||||
dev->dev.parent = parent;
|
||||
|
||||
ret = amba_device_add(dev);
|
||||
if (ret)
|
||||
return ERR_PTR(ret);
|
||||
|
||||
return dev;
|
||||
}
|
||||
|
||||
/**
|
||||
* amba_device_alloc - allocate an AMBA device
|
||||
* @name: sysfs name of the AMBA device
|
||||
* @base: base of AMBA device
|
||||
* @size: size of AMBA device
|
||||
*
|
||||
* Allocate and initialize an AMBA device structure. Returns %NULL
|
||||
* on failure.
|
||||
*/
|
||||
struct amba_device *amba_device_alloc(const char *name, int id, resource_size_t base,
|
||||
size_t size)
|
||||
{
|
||||
struct amba_device *dev;
|
||||
|
||||
dev = xzalloc(sizeof(*dev));
|
||||
|
||||
strcpy(dev->dev.name, name);
|
||||
dev->dev.id = id;
|
||||
dev->res.start = base;
|
||||
dev->res.end = base + size - 1;
|
||||
dev->res.flags = IORESOURCE_MEM;
|
||||
|
||||
return dev;
|
||||
}
|
||||
|
|
@ -0,0 +1,153 @@
|
|||
/*
|
||||
* linux/include/amba/bus.h
|
||||
*
|
||||
* This device type deals with ARM PrimeCells and anything else that
|
||||
* presents a proper CID (0xB105F00D) at the end of the I/O register
|
||||
* region or that is derived from a PrimeCell.
|
||||
*
|
||||
* Copyright (C) 2003 Deep Blue Solutions Ltd, All Rights Reserved.
|
||||
*
|
||||
* 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.
|
||||
*/
|
||||
#ifndef ASMARM_AMBA_H
|
||||
#define ASMARM_AMBA_H
|
||||
|
||||
#include <linux/clk.h>
|
||||
#include <driver.h>
|
||||
#include <linux/err.h>
|
||||
|
||||
#define AMBA_CID 0xb105f00d
|
||||
|
||||
/**
|
||||
* struct amba_id - identifies a device on an AMBA bus
|
||||
* @id: The significant bits if the hardware device ID
|
||||
* @mask: Bitmask specifying which bits of the id field are significant when
|
||||
* matching. A driver binds to a device when ((hardware device ID) & mask)
|
||||
* == id.
|
||||
* @data: Private data used by the driver.
|
||||
*/
|
||||
struct amba_id {
|
||||
unsigned int id;
|
||||
unsigned int mask;
|
||||
void *data;
|
||||
};
|
||||
|
||||
struct clk;
|
||||
|
||||
struct amba_device {
|
||||
struct device_d dev;
|
||||
struct resource res;
|
||||
void __iomem *base;
|
||||
struct clk *pclk;
|
||||
unsigned int periphid;
|
||||
};
|
||||
|
||||
struct amba_driver {
|
||||
struct driver_d drv;
|
||||
int (*probe)(struct amba_device *, const struct amba_id *);
|
||||
int (*remove)(struct amba_device *);
|
||||
const struct amba_id *id_table;
|
||||
};
|
||||
|
||||
enum amba_vendor {
|
||||
AMBA_VENDOR_ARM = 0x41,
|
||||
AMBA_VENDOR_ST = 0x80,
|
||||
};
|
||||
|
||||
extern struct bus_type amba_bustype;
|
||||
|
||||
#define to_amba_device(d) container_of(d, struct amba_device, dev)
|
||||
|
||||
#define amba_get_drvdata(d) dev_get_drvdata(&d->dev)
|
||||
#define amba_set_drvdata(d,p) dev_set_drvdata(&d->dev, p)
|
||||
|
||||
int amba_driver_register(struct amba_driver *);
|
||||
void amba_driver_unregister(struct amba_driver *);
|
||||
struct amba_device *amba_device_alloc(const char *, int id, resource_size_t, size_t);
|
||||
void amba_device_put(struct amba_device *);
|
||||
int amba_device_add(struct amba_device *);
|
||||
int amba_device_register(struct amba_device *, struct resource *);
|
||||
|
||||
struct amba_device *
|
||||
amba_aphb_device_add(struct device_d *parent, const char *name, int id,
|
||||
resource_size_t base, size_t size,
|
||||
void *pdata, unsigned int periphid);
|
||||
|
||||
static inline struct amba_device *
|
||||
amba_apb_device_add(struct device_d *parent, const char *name, int id,
|
||||
resource_size_t base, size_t size,
|
||||
void *pdata, unsigned int periphid)
|
||||
{
|
||||
return amba_aphb_device_add(parent, name, id, base, size, pdata,
|
||||
periphid);
|
||||
}
|
||||
|
||||
static inline struct amba_device *
|
||||
amba_ahb_device_add(struct device_d *parent, const char *name, int id,
|
||||
resource_size_t base, size_t size,
|
||||
void *pdata, unsigned int periphid)
|
||||
{
|
||||
return amba_aphb_device_add(parent, name, id, base, size, pdata,
|
||||
periphid);
|
||||
}
|
||||
|
||||
|
||||
void amba_device_unregister(struct amba_device *);
|
||||
struct amba_device *amba_find_device(const char *, struct device_d *, unsigned int, unsigned int);
|
||||
int amba_request_regions(struct amba_device *, const char *);
|
||||
void amba_release_regions(struct amba_device *);
|
||||
|
||||
static inline void __iomem *amba_get_mem_region(struct amba_device *dev)
|
||||
{
|
||||
return dev->base;
|
||||
}
|
||||
|
||||
#define amba_pclk_enable(d) \
|
||||
(IS_ERR((d)->pclk) ? 0 : clk_enable((d)->pclk))
|
||||
|
||||
#define amba_pclk_disable(d) \
|
||||
do { if (!IS_ERR((d)->pclk)) clk_disable((d)->pclk); } while (0)
|
||||
|
||||
/* Some drivers don't use the struct amba_device */
|
||||
#define AMBA_CONFIG_BITS(a) (((a) >> 24) & 0xff)
|
||||
#define AMBA_REV_BITS(a) (((a) >> 20) & 0x0f)
|
||||
#define AMBA_MANF_BITS(a) (((a) >> 12) & 0xff)
|
||||
#define AMBA_PART_BITS(a) ((a) & 0xfff)
|
||||
|
||||
#define amba_config(d) AMBA_CONFIG_BITS((d)->periphid)
|
||||
#define amba_rev(d) AMBA_REV_BITS((d)->periphid)
|
||||
#define amba_manf(d) AMBA_MANF_BITS((d)->periphid)
|
||||
#define amba_part(d) AMBA_PART_BITS((d)->periphid)
|
||||
|
||||
#define __AMBA_DEV(busid, data) \
|
||||
{ \
|
||||
.init_name = busid, \
|
||||
.platform_data = data, \
|
||||
}
|
||||
|
||||
/*
|
||||
* APB devices do not themselves have the ability to address memory,
|
||||
* so DMA masks should be zero (much like USB peripheral devices.)
|
||||
* The DMA controller DMA masks should be used instead (much like
|
||||
* USB host controllers in conventional PCs.)
|
||||
*/
|
||||
#define AMBA_APB_DEVICE(name, busid, id, base, data) \
|
||||
struct amba_device name##_device = { \
|
||||
.dev = __AMBA_DEV(busid, data), \
|
||||
.res = DEFINE_RES_MEM(base, SZ_4K), \
|
||||
.periphid = id, \
|
||||
}
|
||||
|
||||
/*
|
||||
* AHB devices are DMA capable, so set their DMA masks
|
||||
*/
|
||||
#define AMBA_AHB_DEVICE(name, busid, id, base, data) \
|
||||
struct amba_device name##_device = { \
|
||||
.dev = __AMBA_DEV(busid, data), \
|
||||
.res = DEFINE_RES_MEM(base, SZ_4K), \
|
||||
.periphid = id, \
|
||||
}
|
||||
|
||||
#endif
|
Loading…
Reference in New Issue