/* * arch/arm/mach-iop13xx/msi.c * * PCI MSI support for the iop13xx processor * * Copyright (c) 2006, Intel Corporation. * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along with * this program; if not, write to the Free Software Foundation, Inc., 59 Temple * Place - Suite 330, Boston, MA 02111-1307 USA. * */ #include <linux/pci.h> #include <linux/msi.h> #include <asm/mach/irq.h> #include <asm/irq.h> #define IOP13XX_NUM_MSI_IRQS 128 static DECLARE_BITMAP(msi_irq_in_use, IOP13XX_NUM_MSI_IRQS); /* IMIPR0 CP6 R8 Page 1 */ static u32 read_imipr_0(void) { u32 val; asm volatile("mrc p6, 0, %0, c8, c1, 0":"=r" (val)); return val; } static void write_imipr_0(u32 val) { asm volatile("mcr p6, 0, %0, c8, c1, 0"::"r" (val)); } /* IMIPR1 CP6 R9 Page 1 */ static u32 read_imipr_1(void) { u32 val; asm volatile("mrc p6, 0, %0, c9, c1, 0":"=r" (val)); return val; } static void write_imipr_1(u32 val) { asm volatile("mcr p6, 0, %0, c9, c1, 0"::"r" (val)); } /* IMIPR2 CP6 R10 Page 1 */ static u32 read_imipr_2(void) { u32 val; asm volatile("mrc p6, 0, %0, c10, c1, 0":"=r" (val)); return val; } static void write_imipr_2(u32 val) { asm volatile("mcr p6, 0, %0, c10, c1, 0"::"r" (val)); } /* IMIPR3 CP6 R11 Page 1 */ static u32 read_imipr_3(void) { u32 val; asm volatile("mrc p6, 0, %0, c11, c1, 0":"=r" (val)); return val; } static void write_imipr_3(u32 val) { asm volatile("mcr p6, 0, %0, c11, c1, 0"::"r" (val)); } static u32 (*read_imipr[])(void) = { read_imipr_0, read_imipr_1, read_imipr_2, read_imipr_3, }; static void (*write_imipr[])(u32) = { write_imipr_0, write_imipr_1, write_imipr_2, write_imipr_3, }; static void iop13xx_msi_handler(unsigned int irq, struct irq_desc *desc) { int i, j; unsigned long status; /* read IMIPR registers and find any active interrupts, * then call ISR for each active interrupt */ for (i = 0; i < ARRAY_SIZE(read_imipr); i++) { status = (read_imipr[i])(); if (!status) continue; do { j = find_first_bit(&status, 32); (write_imipr[i])(1 << j); /* write back to clear bit */ generic_handle_irq(IRQ_IOP13XX_MSI_0 + j + (32*i)); status = (read_imipr[i])(); } while (status); } } void __init iop13xx_msi_init(void) { set_irq_chained_handler(IRQ_IOP13XX_INBD_MSI, iop13xx_msi_handler); } /* * Dynamic irq allocate and deallocation */ int create_irq(void) { int irq, pos; again: pos = find_first_zero_bit(msi_irq_in_use, IOP13XX_NUM_MSI_IRQS); irq = IRQ_IOP13XX_MSI_0 + pos; if (irq > NR_IRQS) return -ENOSPC; /* test_and_set_bit operates on 32-bits at a time */ if (test_and_set_bit(pos, msi_irq_in_use)) goto again; dynamic_irq_init(irq); return irq; } void destroy_irq(unsigned int irq) { int pos = irq - IRQ_IOP13XX_MSI_0; dynamic_irq_cleanup(irq); clear_bit(pos, msi_irq_in_use); } void arch_teardown_msi_irq(unsigned int irq) { destroy_irq(irq); } static void iop13xx_msi_nop(unsigned int irq) { return; } static struct irq_chip iop13xx_msi_chip = { .name = "PCI-MSI", .ack = iop13xx_msi_nop, .enable = unmask_msi_irq, .disable = mask_msi_irq, .mask = mask_msi_irq, .unmask = unmask_msi_irq, }; int arch_setup_msi_irq(struct pci_dev *pdev, struct msi_desc *desc) { int id, irq = create_irq(); struct msi_msg msg; if (irq < 0) return irq; set_irq_msi(irq, desc); msg.address_hi = 0x0; msg.address_lo = IOP13XX_MU_MIMR_PCI; id = iop13xx_cpu_id(); msg.data = (id << IOP13XX_MU_MIMR_CORE_SELECT) | (irq & 0x7f); write_msi_msg(irq, &msg); set_irq_chip_and_handler(irq, &iop13xx_msi_chip, handle_simple_irq); return 0; }