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authorIngo Molnar <mingo@kernel.org>2012-04-14 13:18:27 +0200
committerIngo Molnar <mingo@kernel.org>2012-04-14 13:19:04 +0200
commit6ac1ef482d7ae0c690f1640bf6eb818ff9a2d91e (patch)
tree021cc9f6b477146fcebe6f3be4752abfa2ba18a9 /arch/powerpc/sysdev/mpic_msgr.c
parent682968e0c425c60f0dde37977e5beb2b12ddc4cc (diff)
parenta385ec4f11bdcf81af094c03e2444ee9b7fad2e5 (diff)
Merge branch 'perf/core' into perf/uprobes
Merge in latest upstream (and the latest perf development tree), to prepare for tooling changes, and also to pick up v3.4 MM changes that the uprobes code needs to take care of. Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/powerpc/sysdev/mpic_msgr.c')
-rw-r--r--arch/powerpc/sysdev/mpic_msgr.c282
1 files changed, 282 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/mpic_msgr.c b/arch/powerpc/sysdev/mpic_msgr.c
new file mode 100644
index 00000000000..6e7fa386e76
--- /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);