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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /arch/powerpc/sysdev/mpic_msgr.c | |
parent | Initial commit. (diff) | |
download | linux-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.c | 286 |
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); |