|  | /* | 
|  | * 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 DEFINE_RAW_SPINLOCK(msgrs_lock); | 
|  |  | 
|  | 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(&msgrs_lock, flags); | 
|  | msgr = mpic_msgrs[reg_num]; | 
|  | if (msgr->in_use == MSGR_FREE) | 
|  | msgr->in_use = MSGR_INUSE; | 
|  | raw_spin_unlock_irqrestore(&msgrs_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 = (u32 *)((u8 *)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); |