alistair23-linux/include/linux/amba/bus.h
Ulf Hansson f458488425 amba: Initialize dma_parms for amba devices
It's currently the amba driver's responsibility to initialize the pointer,
dma_parms, for its corresponding struct device. The benefit with this
approach allows us to avoid the initialization and to not waste memory for
the struct device_dma_parameters, as this can be decided on a case by case
basis.

However, it has turned out that this approach is not very practical. Not
only does it lead to open coding, but also to real errors. In principle
callers of dma_set_max_seg_size() doesn't check the error code, but just
assumes it succeeds.

For these reasons, let's do the initialization from the common amba bus at
the device registration point. This also follows the way the PCI devices
are being managed, see pci_device_add().

Suggested-by: Christoph Hellwig <hch@lst.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: <stable@vger.kernel.org>
Tested-by: Haibo Chen <haibo.chen@nxp.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20200422101013.31267-1-ulf.hansson@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-28 17:44:34 +02:00

219 lines
6.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* 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.
*/
#ifndef ASMARM_AMBA_H
#define ASMARM_AMBA_H
#include <linux/clk.h>
#include <linux/device.h>
#include <linux/mod_devicetable.h>
#include <linux/err.h>
#include <linux/resource.h>
#include <linux/regulator/consumer.h>
#define AMBA_NR_IRQS 9
#define AMBA_CID 0xb105f00d
#define CORESIGHT_CID 0xb105900d
/*
* CoreSight Architecture specification updates the ID specification
* for components on the AMBA bus. (ARM IHI 0029E)
*
* Bits 15:12 of the CID are the device class.
*
* Class 0xF remains for PrimeCell and legacy components. (AMBA_CID above)
* Class 0x9 defines the component as CoreSight (CORESIGHT_CID above)
* Class 0x0, 0x1, 0xB, 0xE define components that do not have driver support
* at present.
* Class 0x2-0x8,0xA and 0xD-0xD are presently reserved.
*
* Remaining CID bits stay as 0xb105-00d
*/
/**
* Class 0x9 components use additional values to form a Unique Component
* Identifier (UCI), where peripheral ID values are identical for different
* components. Passed to the amba bus code from the component driver via
* the amba_id->data pointer.
* @devarch : coresight devarch register value
* @devarch_mask: mask bits used for matching. 0 indicates UCI not used.
* @devtype : coresight device type value
* @data : additional driver data. As we have usurped the original
* pointer some devices may still need additional data
*/
struct amba_cs_uci_id {
unsigned int devarch;
unsigned int devarch_mask;
unsigned int devtype;
void *data;
};
/* define offsets for registers used by UCI */
#define UCI_REG_DEVTYPE_OFFSET 0xFCC
#define UCI_REG_DEVARCH_OFFSET 0xFBC
struct clk;
struct amba_device {
struct device dev;
struct resource res;
struct clk *pclk;
struct device_dma_parameters dma_parms;
unsigned int periphid;
unsigned int cid;
struct amba_cs_uci_id uci;
unsigned int irq[AMBA_NR_IRQS];
char *driver_override;
};
struct amba_driver {
struct device_driver drv;
int (*probe)(struct amba_device *, const struct amba_id *);
int (*remove)(struct amba_device *);
void (*shutdown)(struct amba_device *);
const struct amba_id *id_table;
};
/*
* Constants for the designer field of the Peripheral ID register. When bit 7
* is set to '1', bits [6:0] should be the JEP106 manufacturer identity code.
*/
enum amba_vendor {
AMBA_VENDOR_ARM = 0x41,
AMBA_VENDOR_ST = 0x80,
AMBA_VENDOR_QCOM = 0x51,
AMBA_VENDOR_LSI = 0xb6,
AMBA_VENDOR_LINUX = 0xfe, /* This value is not official */
};
/* This is used to generate pseudo-ID for AMBA device */
#define AMBA_LINUX_ID(conf, rev, part) \
(((conf) & 0xff) << 24 | ((rev) & 0xf) << 20 | \
AMBA_VENDOR_LINUX << 12 | ((part) & 0xfff))
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 *, resource_size_t, size_t);
void amba_device_put(struct amba_device *);
int amba_device_add(struct amba_device *, struct resource *);
int amba_device_register(struct amba_device *, struct resource *);
struct amba_device *amba_apb_device_add(struct device *parent, const char *name,
resource_size_t base, size_t size,
int irq1, int irq2, void *pdata,
unsigned int periphid);
struct amba_device *amba_ahb_device_add(struct device *parent, const char *name,
resource_size_t base, size_t size,
int irq1, int irq2, void *pdata,
unsigned int periphid);
struct amba_device *
amba_apb_device_add_res(struct device *parent, const char *name,
resource_size_t base, size_t size, int irq1,
int irq2, void *pdata, unsigned int periphid,
struct resource *resbase);
struct amba_device *
amba_ahb_device_add_res(struct device *parent, const char *name,
resource_size_t base, size_t size, int irq1,
int irq2, void *pdata, unsigned int periphid,
struct resource *resbase);
void amba_device_unregister(struct amba_device *);
struct amba_device *amba_find_device(const char *, struct device *, unsigned int, unsigned int);
int amba_request_regions(struct amba_device *, const char *);
void amba_release_regions(struct amba_device *);
static inline int amba_pclk_enable(struct amba_device *dev)
{
return clk_enable(dev->pclk);
}
static inline void amba_pclk_disable(struct amba_device *dev)
{
clk_disable(dev->pclk);
}
static inline int amba_pclk_prepare(struct amba_device *dev)
{
return clk_prepare(dev->pclk);
}
static inline void amba_pclk_unprepare(struct amba_device *dev)
{
clk_unprepare(dev->pclk);
}
/* 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, mask) \
{ \
.coherent_dma_mask = mask, \
.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, irqs, data) \
struct amba_device name##_device = { \
.dev = __AMBA_DEV(busid, data, 0), \
.res = DEFINE_RES_MEM(base, SZ_4K), \
.irq = irqs, \
.periphid = id, \
}
/*
* AHB devices are DMA capable, so set their DMA masks
*/
#define AMBA_AHB_DEVICE(name, busid, id, base, irqs, data) \
struct amba_device name##_device = { \
.dev = __AMBA_DEV(busid, data, ~0ULL), \
.res = DEFINE_RES_MEM(base, SZ_4K), \
.irq = irqs, \
.periphid = id, \
}
/*
* module_amba_driver() - Helper macro for drivers that don't do anything
* special in module init/exit. This eliminates a lot of boilerplate. Each
* module may only use this macro once, and calling it replaces module_init()
* and module_exit()
*/
#define module_amba_driver(__amba_drv) \
module_driver(__amba_drv, amba_driver_register, amba_driver_unregister)
/*
* builtin_amba_driver() - Helper macro for drivers that don't do anything
* special in driver initcall. This eliminates a lot of boilerplate. Each
* driver may only use this macro once, and calling it replaces the instance
* device_initcall().
*/
#define builtin_amba_driver(__amba_drv) \
builtin_driver(__amba_drv, amba_driver_register)
#endif