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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/powerpc/sysdev/mpic_msgr.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/sysdev/mpic_msgr.c')
-rw-r--r--arch/powerpc/sysdev/mpic_msgr.c286
1 files changed, 286 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/mpic_msgr.c b/arch/powerpc/sysdev/mpic_msgr.c
new file mode 100644
index 0000000000..7b449cc51a
--- /dev/null
+++ b/arch/powerpc/sysdev/mpic_msgr.c
@@ -0,0 +1,286 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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.
+ */
+
+#include <linux/list.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/slab.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 / sizeof(u32))
+#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 inefficient. 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_property_present(aliases, buf))
+ break;
+
+ count += 1;
+ }
+ of_node_put(aliases);
+ }
+
+ 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;
+ struct device_node *tn;
+
+ snprintf(buf, sizeof(buf), "mpic-msgr-block%d", index);
+ prop = of_find_property(aliases, buf, NULL);
+ tn = of_find_node_by_path(prop->value);
+ if (node == tn) {
+ of_node_put(tn);
+ break;
+ }
+ of_node_put(tn);
+ }
+ of_node_put(aliases);
+
+ return index == number_of_blocks ? -1 : index;
+}
+
+/* The probe function for a single message register block.
+ */
+static 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 = kcalloc(mpic_msgr_count, sizeof(*mpic_msgrs),
+ 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 %pOF\n", np);
+
+ /* IO map the message register block. */
+ of_address_to_resource(np, 0, &rsrc);
+ msgr_block_addr = devm_ioremap(&dev->dev, rsrc.start, resource_size(&rsrc));
+ 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)) {
+ msgr->irq = irq_of_parse_and_map(np, irq_index);
+ if (!msgr->irq) {
+ dev_err(&dev->dev,
+ "Missing interrupt specifier");
+ kfree(msgr);
+ return -EFAULT;
+ }
+ irq_index += 1;
+ } else {
+ msgr->irq = 0;
+ }
+
+ 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",
+ .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);