linux/include/asm-arm/arch-ixp2000/platform.h
Lennert Buytenhek b4a1f67fbf [ARM] 3053/1: introduce ixp2000_reg_wrb (ixp2000_reg_write plus readback)
Patch from Lennert Buytenhek

Introduce ixp2000_reg_wrb, which is a variant of ixp2000_reg_write
that does a readback from the target register, to make sure that
the write has been flushed out of the write buffer.

Unlike the previous (ineffective) readback in ixp2000_reg_write, this
readback is followed by an instruction that depends on the value of
the readback so that the CPU actually stalls until the readback has
completed.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2005-10-29 16:28:28 +01:00

152 lines
4.7 KiB
C

/*
* include/asm-arm/arch-ixp2000/platform.h
*
* Various bits of code used by platform-level code.
*
* Author: Deepak Saxena <dsaxena@plexity.net>
*
* Copyright 2004 (c) MontaVista Software, Inc.
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#ifndef __ASSEMBLY__
static inline unsigned long ixp2000_reg_read(volatile void *reg)
{
return *((volatile unsigned long *)reg);
}
static inline void ixp2000_reg_write(volatile void *reg, unsigned long val)
{
*((volatile unsigned long *)reg) = val;
}
/*
* On the IXP2400, we can't use XCB=000 due to chip bugs. We use
* XCB=101 instead, but that makes all I/O accesses bufferable. This
* is not a problem in general, but we do have to be slightly more
* careful because I/O writes are no longer automatically flushed out
* of the write buffer.
*
* In cases where we want to make sure that a write has been flushed
* out of the write buffer before we proceed, for example when masking
* a device interrupt before re-enabling IRQs in CPSR, we can use this
* function, ixp2000_reg_wrb, which performs a write, a readback, and
* issues a dummy instruction dependent on the value of the readback
* (mov rX, rX) to make sure that the readback has completed before we
* continue.
*/
static inline void ixp2000_reg_wrb(volatile void *reg, unsigned long val)
{
unsigned long dummy;
*((volatile unsigned long *)reg) = val;
dummy = *((volatile unsigned long *)reg);
__asm__ __volatile__("mov %0, %0" : "+r" (dummy));
}
/*
* Boards may multiplex different devices on the 2nd channel of
* the slowport interface that each need different configuration
* settings. For example, the IXDP2400 uses channel 2 on the interface
* to access the CPLD, the switch fabric card, and the media card. Each
* one needs a different mode so drivers must save/restore the mode
* before and after each operation.
*
* acquire_slowport(&your_config);
* ...
* do slowport operations
* ...
* release_slowport();
*
* Note that while you have the slowport, you are holding a spinlock,
* so your code should be written as if you explicitly acquired a lock.
*
* The configuration only affects device 2 on the slowport, so the
* MTD map driver does not acquire/release the slowport.
*/
struct slowport_cfg {
unsigned long CCR; /* Clock divide */
unsigned long WTC; /* Write Timing Control */
unsigned long RTC; /* Read Timing Control */
unsigned long PCR; /* Protocol Control Register */
unsigned long ADC; /* Address/Data Width Control */
};
void ixp2000_acquire_slowport(struct slowport_cfg *, struct slowport_cfg *);
void ixp2000_release_slowport(struct slowport_cfg *);
/*
* IXP2400 A0/A1 and IXP2800 A0/A1/A2 have broken slowport that requires
* tweaking of addresses in the MTD driver.
*/
static inline unsigned ixp2000_has_broken_slowport(void)
{
unsigned long id = *IXP2000_PRODUCT_ID;
unsigned long id_prod = id & (IXP2000_MAJ_PROD_TYPE_MASK |
IXP2000_MIN_PROD_TYPE_MASK);
return (((id_prod ==
/* fixed in IXP2400-B0 */
(IXP2000_MAJ_PROD_TYPE_IXP2000 |
IXP2000_MIN_PROD_TYPE_IXP2400)) &&
((id & IXP2000_MAJ_REV_MASK) == 0)) ||
((id_prod ==
/* fixed in IXP2800-B0 */
(IXP2000_MAJ_PROD_TYPE_IXP2000 |
IXP2000_MIN_PROD_TYPE_IXP2800)) &&
((id & IXP2000_MAJ_REV_MASK) == 0)) ||
((id_prod ==
/* fixed in IXP2850-B0 */
(IXP2000_MAJ_PROD_TYPE_IXP2000 |
IXP2000_MIN_PROD_TYPE_IXP2850)) &&
((id & IXP2000_MAJ_REV_MASK) == 0)));
}
static inline unsigned int ixp2000_has_flash(void)
{
return ((*IXP2000_STRAP_OPTIONS) & (CFG_BOOT_PROM));
}
static inline unsigned int ixp2000_is_pcimaster(void)
{
return ((*IXP2000_STRAP_OPTIONS) & (CFG_PCI_BOOT_HOST));
}
void ixp2000_map_io(void);
void ixp2000_uart_init(void);
void ixp2000_init_irq(void);
void ixp2000_init_time(unsigned long);
unsigned long ixp2000_gettimeoffset(void);
struct pci_sys_data;
u32 *ixp2000_pci_config_addr(unsigned int bus, unsigned int devfn, int where);
void ixp2000_pci_preinit(void);
int ixp2000_pci_setup(int, struct pci_sys_data*);
struct pci_bus* ixp2000_pci_scan_bus(int, struct pci_sys_data*);
int ixp2000_pci_read_config(struct pci_bus*, unsigned int, int, int, u32 *);
int ixp2000_pci_write_config(struct pci_bus*, unsigned int, int, int, u32);
/*
* Several of the IXP2000 systems have banked flash so we need to extend the
* flash_platform_data structure with some private pointers
*/
struct ixp2000_flash_data {
struct flash_platform_data *platform_data;
int nr_banks;
unsigned long (*bank_setup)(unsigned long);
};
struct ixp2000_i2c_pins {
unsigned long sda_pin;
unsigned long scl_pin;
};
#endif /* !__ASSEMBLY__ */