linux_dsm_epyc7002/arch/powerpc/include/asm/mpic_msgr.h
Jia Hongtao 8626816e90 powerpc: add support for MPIC message register API
Some MPIC implementations contain one or more blocks of message registers
that are used to send messages between cores via IPIs.  A simple API has
been added to access (get/put, read, write, etc ...) these message registers.
The available message registers are initially discovered via nodes in the
device tree.  A separate commit contains a binding for the message register
nodes.

Signed-off-by: Meador Inge <meador_inge@mentor.com>
Signed-off-by: Jia Hongtao <B38951@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2012-03-16 16:15:28 -05:00

133 lines
3.5 KiB
C

/*
* Copyright 2011-2012, Meador Inge, Mentor Graphics Corporation.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; version 2 of the
* License.
*
*/
#ifndef _ASM_MPIC_MSGR_H
#define _ASM_MPIC_MSGR_H
#include <linux/types.h>
#include <linux/spinlock.h>
struct mpic_msgr {
u32 __iomem *base;
u32 __iomem *mer;
int irq;
unsigned char in_use;
raw_spinlock_t lock;
int num;
};
/* Get a message register
*
* @reg_num: the MPIC message register to get
*
* A pointer to the message register is returned. If
* the message register asked for is already in use, then
* EBUSY is returned. If the number given is not associated
* with an actual message register, then ENODEV is returned.
* Successfully getting the register marks it as in use.
*/
extern struct mpic_msgr *mpic_msgr_get(unsigned int reg_num);
/* Relinquish a message register
*
* @msgr: the message register to return
*
* Disables the given message register and marks it as free.
* After this call has completed successully the message
* register is available to be acquired by a call to
* mpic_msgr_get.
*/
extern void mpic_msgr_put(struct mpic_msgr *msgr);
/* Enable a message register
*
* @msgr: the message register to enable
*
* The given message register is enabled for sending
* messages.
*/
extern void mpic_msgr_enable(struct mpic_msgr *msgr);
/* Disable a message register
*
* @msgr: the message register to disable
*
* The given message register is disabled for sending
* messages.
*/
extern void mpic_msgr_disable(struct mpic_msgr *msgr);
/* Write a message to a message register
*
* @msgr: the message register to write to
* @message: the message to write
*
* The given 32-bit message is written to the given message
* register. Writing to an enabled message registers fires
* an interrupt.
*/
static inline void mpic_msgr_write(struct mpic_msgr *msgr, u32 message)
{
out_be32(msgr->base, message);
}
/* Read a message from a message register
*
* @msgr: the message register to read from
*
* Returns the 32-bit value currently in the given message register.
* Upon reading the register any interrupts for that register are
* cleared.
*/
static inline u32 mpic_msgr_read(struct mpic_msgr *msgr)
{
return in_be32(msgr->base);
}
/* Clear a message register
*
* @msgr: the message register to clear
*
* Clears any interrupts associated with the given message register.
*/
static inline void mpic_msgr_clear(struct mpic_msgr *msgr)
{
(void) mpic_msgr_read(msgr);
}
/* Set the destination CPU for the message register
*
* @msgr: the message register whose destination is to be set
* @cpu_num: the Linux CPU number to bind the message register to
*
* Note that the CPU number given is the CPU number used by the kernel
* and *not* the actual hardware CPU number.
*/
static inline void mpic_msgr_set_destination(struct mpic_msgr *msgr,
u32 cpu_num)
{
out_be32(msgr->base, 1 << get_hard_smp_processor_id(cpu_num));
}
/* Get the IRQ number for the message register
* @msgr: the message register whose IRQ is to be returned
*
* Returns the IRQ number associated with the given message register.
* NO_IRQ is returned if this message register is not capable of
* receiving interrupts. What message register can and cannot receive
* interrupts is specified in the device tree for the system.
*/
static inline int mpic_msgr_get_irq(struct mpic_msgr *msgr)
{
return msgr->irq;
}
#endif