diff options
| -rw-r--r-- | arch/powerpc/include/asm/mpic_msgr.h | 132 | ||||
| -rw-r--r-- | arch/powerpc/platforms/Kconfig | 8 | ||||
| -rw-r--r-- | arch/powerpc/sysdev/Makefile | 2 | ||||
| -rw-r--r-- | arch/powerpc/sysdev/mpic_msgr.c | 282 |
4 files changed, 424 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/mpic_msgr.h b/arch/powerpc/include/asm/mpic_msgr.h new file mode 100644 index 000000000000..3ec37dc9003e --- /dev/null +++ b/arch/powerpc/include/asm/mpic_msgr.h @@ -0,0 +1,132 @@ +/* + * 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 diff --git a/arch/powerpc/platforms/Kconfig b/arch/powerpc/platforms/Kconfig index 236ab67bc3a4..a35ca44ade66 100644 --- a/arch/powerpc/platforms/Kconfig +++ b/arch/powerpc/platforms/Kconfig @@ -86,6 +86,14 @@ config MPIC_WEIRD bool default n +config MPIC_MSGR + bool "MPIC message register support" + depends on MPIC + default n + help + Enables support for the MPIC message registers. These + registers are used for inter-processor communication. + config PPC_I8259 bool default n diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile index f80ff9f5f441..1bd7ecb24620 100644 --- a/arch/powerpc/sysdev/Makefile +++ b/arch/powerpc/sysdev/Makefile @@ -4,6 +4,8 @@ ccflags-$(CONFIG_PPC64) := -mno-minimal-toc mpic-msi-obj-$(CONFIG_PCI_MSI) += mpic_msi.o mpic_u3msi.o mpic_pasemi_msi.o obj-$(CONFIG_MPIC) += mpic.o $(mpic-msi-obj-y) +mpic-msgr-obj-$(CONFIG_MPIC_MSGR) += mpic_msgr.o +obj-$(CONFIG_MPIC) += mpic.o $(mpic-msi-obj-y) $(mpic-msgr-obj-y) obj-$(CONFIG_PPC_EPAPR_HV_PIC) += ehv_pic.o fsl-msi-obj-$(CONFIG_PCI_MSI) += fsl_msi.o obj-$(CONFIG_PPC_MSI_BITMAP) += msi_bitmap.o diff --git a/arch/powerpc/sysdev/mpic_msgr.c b/arch/powerpc/sysdev/mpic_msgr.c new file mode 100644 index 000000000000..6e7fa386e76a --- /dev/null +++ b/arch/powerpc/sysdev/mpic_msgr.c @@ -0,0 +1,282 @@ +/* + * Copyright 2011-2012, Meador Inge, Mentor Graphics Corporation. + * + * Some ideas based on un-pushed work done by Vivek Mahajan, Jason Jin, and + * Mingkai Hu from Freescale Semiconductor, Inc. + * + * 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. + * + */ + +#include <linux/list.h> +#include <linux/of_platform.h> +#include <linux/errno.h> +#include <asm/prom.h> +#include <asm/hw_irq.h> +#include <asm/ppc-pci.h> +#include <asm/mpic_msgr.h> + +#define MPIC_MSGR_REGISTERS_PER_BLOCK 4 +#define MPIC_MSGR_STRIDE 0x10 +#define MPIC_MSGR_MER_OFFSET 0x100 +#define MSGR_INUSE 0 +#define MSGR_FREE 1 + +static struct mpic_msgr **mpic_msgrs; +static unsigned int mpic_msgr_count; + +static inline void _mpic_msgr_mer_write(struct mpic_msgr *msgr, u32 value) +{ + out_be32(msgr->mer, value); +} + +static inline u32 _mpic_msgr_mer_read(struct mpic_msgr *msgr) +{ + return in_be32(msgr->mer); +} + +static inline void _mpic_msgr_disable(struct mpic_msgr *msgr) +{ + u32 mer = _mpic_msgr_mer_read(msgr); + + _mpic_msgr_mer_write(msgr, mer & ~(1 << msgr->num)); +} + +struct mpic_msgr *mpic_msgr_get(unsigned int reg_num) +{ + unsigned long flags; + struct mpic_msgr *msgr; + + /* Assume busy until proven otherwise. */ + msgr = ERR_PTR(-EBUSY); + + if (reg_num >= mpic_msgr_count) + return ERR_PTR(-ENODEV); + + raw_spin_lock_irqsave(&msgr->lock, flags); + if (mpic_msgrs[reg_num]->in_use == MSGR_FREE) { + msgr = mpic_msgrs[reg_num]; + msgr->in_use = MSGR_INUSE; + } + raw_spin_unlock_irqrestore(&msgr->lock, flags); + + return msgr; +} +EXPORT_SYMBOL_GPL(mpic_msgr_get); + +void mpic_msgr_put(struct mpic_msgr *msgr) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&msgr->lock, flags); + msgr->in_use = MSGR_FREE; + _mpic_msgr_disable(msgr); + raw_spin_unlock_irqrestore(&msgr->lock, flags); +} +EXPORT_SYMBOL_GPL(mpic_msgr_put); + +void mpic_msgr_enable(struct mpic_msgr *msgr) +{ + unsigned long flags; + u32 mer; + + raw_spin_lock_irqsave(&msgr->lock, flags); + mer = _mpic_msgr_mer_read(msgr); + _mpic_msgr_mer_write(msgr, mer | (1 << msgr->num)); + raw_spin_unlock_irqrestore(&msgr->lock, flags); +} +EXPORT_SYMBOL_GPL(mpic_msgr_enable); + +void mpic_msgr_disable(struct mpic_msgr *msgr) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&msgr->lock, flags); + _mpic_msgr_disable(msgr); + raw_spin_unlock_irqrestore(&msgr->lock, flags); +} +EXPORT_SYMBOL_GPL(mpic_msgr_disable); + +/* The following three functions are used to compute the order and number of + * the message register blocks. They are clearly very inefficent. However, + * they are called *only* a few times during device initialization. + */ +static unsigned int mpic_msgr_number_of_blocks(void) +{ + unsigned int count; + struct device_node *aliases; + + count = 0; + aliases = of_find_node_by_name(NULL, "aliases"); + + if (aliases) { + char buf[32]; + + for (;;) { + snprintf(buf, sizeof(buf), "mpic-msgr-block%d", count); + if (!of_find_property(aliases, buf, NULL)) + break; + + count += 1; + } + } + + return count; +} + +static unsigned int mpic_msgr_number_of_registers(void) +{ + return mpic_msgr_number_of_blocks() * MPIC_MSGR_REGISTERS_PER_BLOCK; +} + +static int mpic_msgr_block_number(struct device_node *node) +{ + struct device_node *aliases; + unsigned int index, number_of_blocks; + char buf[64]; + + number_of_blocks = mpic_msgr_number_of_blocks(); + aliases = of_find_node_by_name(NULL, "aliases"); + if (!aliases) + return -1; + + for (index = 0; index < number_of_blocks; ++index) { + struct property *prop; + + snprintf(buf, sizeof(buf), "mpic-msgr-block%d", index); + prop = of_find_property(aliases, buf, NULL); + if (node == of_find_node_by_path(prop->value)) + break; + } + + return index == number_of_blocks ? -1 : index; +} + +/* The probe function for a single message register block. + */ +static __devinit int mpic_msgr_probe(struct platform_device *dev) +{ + void __iomem *msgr_block_addr; + int block_number; + struct resource rsrc; + unsigned int i; + unsigned int irq_index; + struct device_node *np = dev->dev.of_node; + unsigned int receive_mask; + const unsigned int *prop; + + if (!np) { + dev_err(&dev->dev, "Device OF-Node is NULL"); + return -EFAULT; + } + + /* Allocate the message register array upon the first device + * registered. + */ + if (!mpic_msgrs) { + mpic_msgr_count = mpic_msgr_number_of_registers(); + dev_info(&dev->dev, "Found %d message registers\n", + mpic_msgr_count); + + mpic_msgrs = kzalloc(sizeof(struct mpic_msgr) * mpic_msgr_count, + GFP_KERNEL); + if (!mpic_msgrs) { + dev_err(&dev->dev, + "No memory for message register blocks\n"); + return -ENOMEM; + } + } + dev_info(&dev->dev, "Of-device full name %s\n", np->full_name); + + /* IO map the message register block. */ + of_address_to_resource(np, 0, &rsrc); + msgr_block_addr = ioremap(rsrc.start, rsrc.end - rsrc.start); + if (!msgr_block_addr) { + dev_err(&dev->dev, "Failed to iomap MPIC message registers"); + return -EFAULT; + } + + /* Ensure the block has a defined order. */ + block_number = mpic_msgr_block_number(np); + if (block_number < 0) { + dev_err(&dev->dev, + "Failed to find message register block alias\n"); + return -ENODEV; + } + dev_info(&dev->dev, "Setting up message register block %d\n", + block_number); + + /* Grab the receive mask which specifies what registers can receive + * interrupts. + */ + prop = of_get_property(np, "mpic-msgr-receive-mask", NULL); + receive_mask = (prop) ? *prop : 0xF; + + /* Build up the appropriate message register data structures. */ + for (i = 0, irq_index = 0; i < MPIC_MSGR_REGISTERS_PER_BLOCK; ++i) { + struct mpic_msgr *msgr; + unsigned int reg_number; + + msgr = kzalloc(sizeof(struct mpic_msgr), GFP_KERNEL); + if (!msgr) { + dev_err(&dev->dev, "No memory for message register\n"); + return -ENOMEM; + } + + reg_number = block_number * MPIC_MSGR_REGISTERS_PER_BLOCK + i; + msgr->base = msgr_block_addr + i * MPIC_MSGR_STRIDE; + msgr->mer = msgr->base + MPIC_MSGR_MER_OFFSET; + msgr->in_use = MSGR_FREE; + msgr->num = i; + raw_spin_lock_init(&msgr->lock); + + if (receive_mask & (1 << i)) { + struct resource irq; + + if (of_irq_to_resource(np, irq_index, &irq) == NO_IRQ) { + dev_err(&dev->dev, + "Missing interrupt specifier"); + kfree(msgr); + return -EFAULT; + } + msgr->irq = irq.start; + irq_index += 1; + } else { + msgr->irq = NO_IRQ; + } + + mpic_msgrs[reg_number] = msgr; + mpic_msgr_disable(msgr); + dev_info(&dev->dev, "Register %d initialized: irq %d\n", + reg_number, msgr->irq); + + } + + return 0; +} + +static const struct of_device_id mpic_msgr_ids[] = { + { + .compatible = "fsl,mpic-v3.1-msgr", + .data = NULL, + }, + {} +}; + +static struct platform_driver mpic_msgr_driver = { + .driver = { + .name = "mpic-msgr", + .owner = THIS_MODULE, + .of_match_table = mpic_msgr_ids, + }, + .probe = mpic_msgr_probe, +}; + +static __init int mpic_msgr_init(void) +{ + return platform_driver_register(&mpic_msgr_driver); +} +subsys_initcall(mpic_msgr_init); |