|  | // SPDX-License-Identifier: GPL-2.0-or-later | 
|  | /* | 
|  | * External Interrupt Controller on Spider South Bridge | 
|  | * | 
|  | * (C) Copyright IBM Deutschland Entwicklung GmbH 2005 | 
|  | * | 
|  | * Author: Arnd Bergmann <arndb@de.ibm.com> | 
|  | */ | 
|  |  | 
|  | #include <linux/interrupt.h> | 
|  | #include <linux/irq.h> | 
|  | #include <linux/ioport.h> | 
|  | #include <linux/of_address.h> | 
|  | #include <linux/of_irq.h> | 
|  | #include <linux/pgtable.h> | 
|  |  | 
|  | #include <asm/io.h> | 
|  |  | 
|  | #include "interrupt.h" | 
|  |  | 
|  | /* register layout taken from Spider spec, table 7.4-4 */ | 
|  | enum { | 
|  | TIR_DEN		= 0x004, /* Detection Enable Register */ | 
|  | TIR_MSK		= 0x084, /* Mask Level Register */ | 
|  | TIR_EDC		= 0x0c0, /* Edge Detection Clear Register */ | 
|  | TIR_PNDA	= 0x100, /* Pending Register A */ | 
|  | TIR_PNDB	= 0x104, /* Pending Register B */ | 
|  | TIR_CS		= 0x144, /* Current Status Register */ | 
|  | TIR_LCSA	= 0x150, /* Level Current Status Register A */ | 
|  | TIR_LCSB	= 0x154, /* Level Current Status Register B */ | 
|  | TIR_LCSC	= 0x158, /* Level Current Status Register C */ | 
|  | TIR_LCSD	= 0x15c, /* Level Current Status Register D */ | 
|  | TIR_CFGA	= 0x200, /* Setting Register A0 */ | 
|  | TIR_CFGB	= 0x204, /* Setting Register B0 */ | 
|  | /* 0x208 ... 0x3ff Setting Register An/Bn */ | 
|  | TIR_PPNDA	= 0x400, /* Packet Pending Register A */ | 
|  | TIR_PPNDB	= 0x404, /* Packet Pending Register B */ | 
|  | TIR_PIERA	= 0x408, /* Packet Output Error Register A */ | 
|  | TIR_PIERB	= 0x40c, /* Packet Output Error Register B */ | 
|  | TIR_PIEN	= 0x444, /* Packet Output Enable Register */ | 
|  | TIR_PIPND	= 0x454, /* Packet Output Pending Register */ | 
|  | TIRDID		= 0x484, /* Spider Device ID Register */ | 
|  | REISTIM		= 0x500, /* Reissue Command Timeout Time Setting */ | 
|  | REISTIMEN	= 0x504, /* Reissue Command Timeout Setting */ | 
|  | REISWAITEN	= 0x508, /* Reissue Wait Control*/ | 
|  | }; | 
|  |  | 
|  | #define SPIDER_CHIP_COUNT	4 | 
|  | #define SPIDER_SRC_COUNT	64 | 
|  | #define SPIDER_IRQ_INVALID	63 | 
|  |  | 
|  | struct spider_pic { | 
|  | struct irq_domain		*host; | 
|  | void __iomem		*regs; | 
|  | unsigned int		node_id; | 
|  | }; | 
|  | static struct spider_pic spider_pics[SPIDER_CHIP_COUNT]; | 
|  |  | 
|  | static struct spider_pic *spider_irq_data_to_pic(struct irq_data *d) | 
|  | { | 
|  | return irq_data_get_irq_chip_data(d); | 
|  | } | 
|  |  | 
|  | static void __iomem *spider_get_irq_config(struct spider_pic *pic, | 
|  | unsigned int src) | 
|  | { | 
|  | return pic->regs + TIR_CFGA + 8 * src; | 
|  | } | 
|  |  | 
|  | static void spider_unmask_irq(struct irq_data *d) | 
|  | { | 
|  | struct spider_pic *pic = spider_irq_data_to_pic(d); | 
|  | void __iomem *cfg = spider_get_irq_config(pic, irqd_to_hwirq(d)); | 
|  |  | 
|  | out_be32(cfg, in_be32(cfg) | 0x30000000u); | 
|  | } | 
|  |  | 
|  | static void spider_mask_irq(struct irq_data *d) | 
|  | { | 
|  | struct spider_pic *pic = spider_irq_data_to_pic(d); | 
|  | void __iomem *cfg = spider_get_irq_config(pic, irqd_to_hwirq(d)); | 
|  |  | 
|  | out_be32(cfg, in_be32(cfg) & ~0x30000000u); | 
|  | } | 
|  |  | 
|  | static void spider_ack_irq(struct irq_data *d) | 
|  | { | 
|  | struct spider_pic *pic = spider_irq_data_to_pic(d); | 
|  | unsigned int src = irqd_to_hwirq(d); | 
|  |  | 
|  | /* Reset edge detection logic if necessary | 
|  | */ | 
|  | if (irqd_is_level_type(d)) | 
|  | return; | 
|  |  | 
|  | /* Only interrupts 47 to 50 can be set to edge */ | 
|  | if (src < 47 || src > 50) | 
|  | return; | 
|  |  | 
|  | /* Perform the clear of the edge logic */ | 
|  | out_be32(pic->regs + TIR_EDC, 0x100 | (src & 0xf)); | 
|  | } | 
|  |  | 
|  | static int spider_set_irq_type(struct irq_data *d, unsigned int type) | 
|  | { | 
|  | unsigned int sense = type & IRQ_TYPE_SENSE_MASK; | 
|  | struct spider_pic *pic = spider_irq_data_to_pic(d); | 
|  | unsigned int hw = irqd_to_hwirq(d); | 
|  | void __iomem *cfg = spider_get_irq_config(pic, hw); | 
|  | u32 old_mask; | 
|  | u32 ic; | 
|  |  | 
|  | /* Note that only level high is supported for most interrupts */ | 
|  | if (sense != IRQ_TYPE_NONE && sense != IRQ_TYPE_LEVEL_HIGH && | 
|  | (hw < 47 || hw > 50)) | 
|  | return -EINVAL; | 
|  |  | 
|  | /* Decode sense type */ | 
|  | switch(sense) { | 
|  | case IRQ_TYPE_EDGE_RISING: | 
|  | ic = 0x3; | 
|  | break; | 
|  | case IRQ_TYPE_EDGE_FALLING: | 
|  | ic = 0x2; | 
|  | break; | 
|  | case IRQ_TYPE_LEVEL_LOW: | 
|  | ic = 0x0; | 
|  | break; | 
|  | case IRQ_TYPE_LEVEL_HIGH: | 
|  | case IRQ_TYPE_NONE: | 
|  | ic = 0x1; | 
|  | break; | 
|  | default: | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | /* Configure the source. One gross hack that was there before and | 
|  | * that I've kept around is the priority to the BE which I set to | 
|  | * be the same as the interrupt source number. I don't know whether | 
|  | * that's supposed to make any kind of sense however, we'll have to | 
|  | * decide that, but for now, I'm not changing the behaviour. | 
|  | */ | 
|  | old_mask = in_be32(cfg) & 0x30000000u; | 
|  | out_be32(cfg, old_mask | (ic << 24) | (0x7 << 16) | | 
|  | (pic->node_id << 4) | 0xe); | 
|  | out_be32(cfg + 4, (0x2 << 16) | (hw & 0xff)); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static struct irq_chip spider_pic = { | 
|  | .name = "SPIDER", | 
|  | .irq_unmask = spider_unmask_irq, | 
|  | .irq_mask = spider_mask_irq, | 
|  | .irq_ack = spider_ack_irq, | 
|  | .irq_set_type = spider_set_irq_type, | 
|  | }; | 
|  |  | 
|  | static int spider_host_map(struct irq_domain *h, unsigned int virq, | 
|  | irq_hw_number_t hw) | 
|  | { | 
|  | irq_set_chip_data(virq, h->host_data); | 
|  | irq_set_chip_and_handler(virq, &spider_pic, handle_level_irq); | 
|  |  | 
|  | /* Set default irq type */ | 
|  | irq_set_irq_type(virq, IRQ_TYPE_NONE); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int spider_host_xlate(struct irq_domain *h, struct device_node *ct, | 
|  | const u32 *intspec, unsigned int intsize, | 
|  | irq_hw_number_t *out_hwirq, unsigned int *out_flags) | 
|  |  | 
|  | { | 
|  | /* Spider interrupts have 2 cells, first is the interrupt source, | 
|  | * second, well, I don't know for sure yet ... We mask the top bits | 
|  | * because old device-trees encode a node number in there | 
|  | */ | 
|  | *out_hwirq = intspec[0] & 0x3f; | 
|  | *out_flags = IRQ_TYPE_LEVEL_HIGH; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static const struct irq_domain_ops spider_host_ops = { | 
|  | .map = spider_host_map, | 
|  | .xlate = spider_host_xlate, | 
|  | }; | 
|  |  | 
|  | static void spider_irq_cascade(struct irq_desc *desc) | 
|  | { | 
|  | struct irq_chip *chip = irq_desc_get_chip(desc); | 
|  | struct spider_pic *pic = irq_desc_get_handler_data(desc); | 
|  | unsigned int cs; | 
|  |  | 
|  | cs = in_be32(pic->regs + TIR_CS) >> 24; | 
|  | if (cs != SPIDER_IRQ_INVALID) | 
|  | generic_handle_domain_irq(pic->host, cs); | 
|  |  | 
|  | chip->irq_eoi(&desc->irq_data); | 
|  | } | 
|  |  | 
|  | /* For hooking up the cascade we have a problem. Our device-tree is | 
|  | * crap and we don't know on which BE iic interrupt we are hooked on at | 
|  | * least not the "standard" way. We can reconstitute it based on two | 
|  | * informations though: which BE node we are connected to and whether | 
|  | * we are connected to IOIF0 or IOIF1. Right now, we really only care | 
|  | * about the IBM cell blade and we know that its firmware gives us an | 
|  | * interrupt-map property which is pretty strange. | 
|  | */ | 
|  | static unsigned int __init spider_find_cascade_and_node(struct spider_pic *pic) | 
|  | { | 
|  | unsigned int virq; | 
|  | const u32 *imap, *tmp; | 
|  | int imaplen, intsize, unit; | 
|  | struct device_node *iic; | 
|  | struct device_node *of_node; | 
|  |  | 
|  | of_node = irq_domain_get_of_node(pic->host); | 
|  |  | 
|  | /* First, we check whether we have a real "interrupts" in the device | 
|  | * tree in case the device-tree is ever fixed | 
|  | */ | 
|  | virq = irq_of_parse_and_map(of_node, 0); | 
|  | if (virq) | 
|  | return virq; | 
|  |  | 
|  | /* Now do the horrible hacks */ | 
|  | tmp = of_get_property(of_node, "#interrupt-cells", NULL); | 
|  | if (tmp == NULL) | 
|  | return 0; | 
|  | intsize = *tmp; | 
|  | imap = of_get_property(of_node, "interrupt-map", &imaplen); | 
|  | if (imap == NULL || imaplen < (intsize + 1)) | 
|  | return 0; | 
|  | iic = of_find_node_by_phandle(imap[intsize]); | 
|  | if (iic == NULL) | 
|  | return 0; | 
|  | imap += intsize + 1; | 
|  | tmp = of_get_property(iic, "#interrupt-cells", NULL); | 
|  | if (tmp == NULL) { | 
|  | of_node_put(iic); | 
|  | return 0; | 
|  | } | 
|  | intsize = *tmp; | 
|  | /* Assume unit is last entry of interrupt specifier */ | 
|  | unit = imap[intsize - 1]; | 
|  | /* Ok, we have a unit, now let's try to get the node */ | 
|  | tmp = of_get_property(iic, "ibm,interrupt-server-ranges", NULL); | 
|  | if (tmp == NULL) { | 
|  | of_node_put(iic); | 
|  | return 0; | 
|  | } | 
|  | /* ugly as hell but works for now */ | 
|  | pic->node_id = (*tmp) >> 1; | 
|  | of_node_put(iic); | 
|  |  | 
|  | /* Ok, now let's get cracking. You may ask me why I just didn't match | 
|  | * the iic host from the iic OF node, but that way I'm still compatible | 
|  | * with really really old old firmwares for which we don't have a node | 
|  | */ | 
|  | /* Manufacture an IIC interrupt number of class 2 */ | 
|  | virq = irq_create_mapping(NULL, | 
|  | (pic->node_id << IIC_IRQ_NODE_SHIFT) | | 
|  | (2 << IIC_IRQ_CLASS_SHIFT) | | 
|  | unit); | 
|  | if (!virq) | 
|  | printk(KERN_ERR "spider_pic: failed to map cascade !"); | 
|  | return virq; | 
|  | } | 
|  |  | 
|  |  | 
|  | static void __init spider_init_one(struct device_node *of_node, int chip, | 
|  | unsigned long addr) | 
|  | { | 
|  | struct spider_pic *pic = &spider_pics[chip]; | 
|  | int i, virq; | 
|  |  | 
|  | /* Map registers */ | 
|  | pic->regs = ioremap(addr, 0x1000); | 
|  | if (pic->regs == NULL) | 
|  | panic("spider_pic: can't map registers !"); | 
|  |  | 
|  | /* Allocate a host */ | 
|  | pic->host = irq_domain_add_linear(of_node, SPIDER_SRC_COUNT, | 
|  | &spider_host_ops, pic); | 
|  | if (pic->host == NULL) | 
|  | panic("spider_pic: can't allocate irq host !"); | 
|  |  | 
|  | /* Go through all sources and disable them */ | 
|  | for (i = 0; i < SPIDER_SRC_COUNT; i++) { | 
|  | void __iomem *cfg = pic->regs + TIR_CFGA + 8 * i; | 
|  | out_be32(cfg, in_be32(cfg) & ~0x30000000u); | 
|  | } | 
|  |  | 
|  | /* do not mask any interrupts because of level */ | 
|  | out_be32(pic->regs + TIR_MSK, 0x0); | 
|  |  | 
|  | /* enable interrupt packets to be output */ | 
|  | out_be32(pic->regs + TIR_PIEN, in_be32(pic->regs + TIR_PIEN) | 0x1); | 
|  |  | 
|  | /* Hook up the cascade interrupt to the iic and nodeid */ | 
|  | virq = spider_find_cascade_and_node(pic); | 
|  | if (!virq) | 
|  | return; | 
|  | irq_set_handler_data(virq, pic); | 
|  | irq_set_chained_handler(virq, spider_irq_cascade); | 
|  |  | 
|  | printk(KERN_INFO "spider_pic: node %d, addr: 0x%lx %pOF\n", | 
|  | pic->node_id, addr, of_node); | 
|  |  | 
|  | /* Enable the interrupt detection enable bit. Do this last! */ | 
|  | out_be32(pic->regs + TIR_DEN, in_be32(pic->regs + TIR_DEN) | 0x1); | 
|  | } | 
|  |  | 
|  | void __init spider_init_IRQ(void) | 
|  | { | 
|  | struct resource r; | 
|  | struct device_node *dn; | 
|  | int chip = 0; | 
|  |  | 
|  | /* XXX node numbers are totally bogus. We _hope_ we get the device | 
|  | * nodes in the right order here but that's definitely not guaranteed, | 
|  | * we need to get the node from the device tree instead. | 
|  | * There is currently no proper property for it (but our whole | 
|  | * device-tree is bogus anyway) so all we can do is pray or maybe test | 
|  | * the address and deduce the node-id | 
|  | */ | 
|  | for_each_node_by_name(dn, "interrupt-controller") { | 
|  | if (of_device_is_compatible(dn, "CBEA,platform-spider-pic")) { | 
|  | if (of_address_to_resource(dn, 0, &r)) { | 
|  | printk(KERN_WARNING "spider-pic: Failed\n"); | 
|  | continue; | 
|  | } | 
|  | } else if (of_device_is_compatible(dn, "sti,platform-spider-pic") | 
|  | && (chip < 2)) { | 
|  | static long hard_coded_pics[] = | 
|  | { 0x24000008000ul, 0x34000008000ul}; | 
|  | r.start = hard_coded_pics[chip]; | 
|  | } else | 
|  | continue; | 
|  | spider_init_one(dn, chip++, r.start); | 
|  | } | 
|  | } |