| /* |
| * Copyright 2011 IBM Corporation. |
| * |
| * 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; either version |
| * 2 of the License, or (at your option) any later version. |
| * |
| */ |
| |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| #include <linux/irq.h> |
| #include <linux/smp.h> |
| #include <linux/interrupt.h> |
| #include <linux/init.h> |
| #include <linux/cpu.h> |
| #include <linux/of.h> |
| #include <linux/spinlock.h> |
| |
| #include <asm/prom.h> |
| #include <asm/io.h> |
| #include <asm/smp.h> |
| #include <asm/irq.h> |
| #include <asm/errno.h> |
| #include <asm/xics.h> |
| |
| struct icp_ipl { |
| union { |
| u32 word; |
| u8 bytes[4]; |
| } xirr_poll; |
| union { |
| u32 word; |
| u8 bytes[4]; |
| } xirr; |
| u32 dummy; |
| union { |
| u32 word; |
| u8 bytes[4]; |
| } qirr; |
| u32 link_a; |
| u32 link_b; |
| u32 link_c; |
| }; |
| |
| static struct icp_ipl __iomem *icp_native_regs[NR_CPUS]; |
| |
| static inline unsigned int icp_native_get_xirr(void) |
| { |
| int cpu = smp_processor_id(); |
| |
| return in_be32(&icp_native_regs[cpu]->xirr.word); |
| } |
| |
| static inline void icp_native_set_xirr(unsigned int value) |
| { |
| int cpu = smp_processor_id(); |
| |
| out_be32(&icp_native_regs[cpu]->xirr.word, value); |
| } |
| |
| static inline void icp_native_set_cppr(u8 value) |
| { |
| int cpu = smp_processor_id(); |
| |
| out_8(&icp_native_regs[cpu]->xirr.bytes[0], value); |
| } |
| |
| static inline void icp_native_set_qirr(int n_cpu, u8 value) |
| { |
| out_8(&icp_native_regs[n_cpu]->qirr.bytes[0], value); |
| } |
| |
| static void icp_native_set_cpu_priority(unsigned char cppr) |
| { |
| xics_set_base_cppr(cppr); |
| icp_native_set_cppr(cppr); |
| iosync(); |
| } |
| |
| static void icp_native_eoi(struct irq_data *d) |
| { |
| unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d); |
| |
| iosync(); |
| icp_native_set_xirr((xics_pop_cppr() << 24) | hw_irq); |
| } |
| |
| static void icp_native_teardown_cpu(void) |
| { |
| int cpu = smp_processor_id(); |
| |
| /* Clear any pending IPI */ |
| icp_native_set_qirr(cpu, 0xff); |
| } |
| |
| static void icp_native_flush_ipi(void) |
| { |
| /* We take the ipi irq but and never return so we |
| * need to EOI the IPI, but want to leave our priority 0 |
| * |
| * should we check all the other interrupts too? |
| * should we be flagging idle loop instead? |
| * or creating some task to be scheduled? |
| */ |
| |
| icp_native_set_xirr((0x00 << 24) | XICS_IPI); |
| } |
| |
| static unsigned int icp_native_get_irq(void) |
| { |
| unsigned int xirr = icp_native_get_xirr(); |
| unsigned int vec = xirr & 0x00ffffff; |
| unsigned int irq; |
| |
| if (vec == XICS_IRQ_SPURIOUS) |
| return NO_IRQ; |
| |
| irq = irq_radix_revmap_lookup(xics_host, vec); |
| if (likely(irq != NO_IRQ)) { |
| xics_push_cppr(vec); |
| return irq; |
| } |
| |
| /* We don't have a linux mapping, so have rtas mask it. */ |
| xics_mask_unknown_vec(vec); |
| |
| /* We might learn about it later, so EOI it */ |
| icp_native_set_xirr(xirr); |
| |
| return NO_IRQ; |
| } |
| |
| #ifdef CONFIG_SMP |
| |
| static void icp_native_cause_ipi(int cpu, unsigned long data) |
| { |
| icp_native_set_qirr(cpu, IPI_PRIORITY); |
| } |
| |
| static irqreturn_t icp_native_ipi_action(int irq, void *dev_id) |
| { |
| int cpu = smp_processor_id(); |
| |
| icp_native_set_qirr(cpu, 0xff); |
| |
| return smp_ipi_demux(); |
| } |
| |
| #endif /* CONFIG_SMP */ |
| |
| static int __init icp_native_map_one_cpu(int hw_id, unsigned long addr, |
| unsigned long size) |
| { |
| char *rname; |
| int i, cpu = -1; |
| |
| /* This may look gross but it's good enough for now, we don't quite |
| * have a hard -> linux processor id matching. |
| */ |
| for_each_possible_cpu(i) { |
| if (!cpu_present(i)) |
| continue; |
| if (hw_id == get_hard_smp_processor_id(i)) { |
| cpu = i; |
| break; |
| } |
| } |
| |
| /* Fail, skip that CPU. Don't print, it's normal, some XICS come up |
| * with way more entries in there than you have CPUs |
| */ |
| if (cpu == -1) |
| return 0; |
| |
| rname = kasprintf(GFP_KERNEL, "CPU %d [0x%x] Interrupt Presentation", |
| cpu, hw_id); |
| |
| if (!request_mem_region(addr, size, rname)) { |
| pr_warning("icp_native: Could not reserve ICP MMIO" |
| " for CPU %d, interrupt server #0x%x\n", |
| cpu, hw_id); |
| return -EBUSY; |
| } |
| |
| icp_native_regs[cpu] = ioremap(addr, size); |
| if (!icp_native_regs[cpu]) { |
| pr_warning("icp_native: Failed ioremap for CPU %d, " |
| "interrupt server #0x%x, addr %#lx\n", |
| cpu, hw_id, addr); |
| release_mem_region(addr, size); |
| return -ENOMEM; |
| } |
| return 0; |
| } |
| |
| static int __init icp_native_init_one_node(struct device_node *np, |
| unsigned int *indx) |
| { |
| unsigned int ilen; |
| const u32 *ireg; |
| int i; |
| int reg_tuple_size; |
| int num_servers = 0; |
| |
| /* This code does the theorically broken assumption that the interrupt |
| * server numbers are the same as the hard CPU numbers. |
| * This happens to be the case so far but we are playing with fire... |
| * should be fixed one of these days. -BenH. |
| */ |
| ireg = of_get_property(np, "ibm,interrupt-server-ranges", &ilen); |
| |
| /* Do that ever happen ? we'll know soon enough... but even good'old |
| * f80 does have that property .. |
| */ |
| WARN_ON((ireg == NULL) || (ilen != 2*sizeof(u32))); |
| |
| if (ireg) { |
| *indx = of_read_number(ireg, 1); |
| if (ilen >= 2*sizeof(u32)) |
| num_servers = of_read_number(ireg + 1, 1); |
| } |
| |
| ireg = of_get_property(np, "reg", &ilen); |
| if (!ireg) { |
| pr_err("icp_native: Can't find interrupt reg property"); |
| return -1; |
| } |
| |
| reg_tuple_size = (of_n_addr_cells(np) + of_n_size_cells(np)) * 4; |
| if (((ilen % reg_tuple_size) != 0) |
| || (num_servers && (num_servers != (ilen / reg_tuple_size)))) { |
| pr_err("icp_native: ICP reg len (%d) != num servers (%d)", |
| ilen / reg_tuple_size, num_servers); |
| return -1; |
| } |
| |
| for (i = 0; i < (ilen / reg_tuple_size); i++) { |
| struct resource r; |
| int err; |
| |
| err = of_address_to_resource(np, i, &r); |
| if (err) { |
| pr_err("icp_native: Could not translate ICP MMIO" |
| " for interrupt server 0x%x (%d)\n", *indx, err); |
| return -1; |
| } |
| |
| if (icp_native_map_one_cpu(*indx, r.start, resource_size(&r))) |
| return -1; |
| |
| (*indx)++; |
| } |
| return 0; |
| } |
| |
| static const struct icp_ops icp_native_ops = { |
| .get_irq = icp_native_get_irq, |
| .eoi = icp_native_eoi, |
| .set_priority = icp_native_set_cpu_priority, |
| .teardown_cpu = icp_native_teardown_cpu, |
| .flush_ipi = icp_native_flush_ipi, |
| #ifdef CONFIG_SMP |
| .ipi_action = icp_native_ipi_action, |
| .cause_ipi = icp_native_cause_ipi, |
| #endif |
| }; |
| |
| int icp_native_init(void) |
| { |
| struct device_node *np; |
| u32 indx = 0; |
| int found = 0; |
| |
| for_each_compatible_node(np, NULL, "ibm,ppc-xicp") |
| if (icp_native_init_one_node(np, &indx) == 0) |
| found = 1; |
| if (!found) { |
| for_each_node_by_type(np, |
| "PowerPC-External-Interrupt-Presentation") { |
| if (icp_native_init_one_node(np, &indx) == 0) |
| found = 1; |
| } |
| } |
| |
| if (found == 0) |
| return -ENODEV; |
| |
| icp_ops = &icp_native_ops; |
| |
| return 0; |
| } |