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-rw-r--r--arch/arm/mach-iop13xx/msi.c194
1 files changed, 194 insertions, 0 deletions
diff --git a/arch/arm/mach-iop13xx/msi.c b/arch/arm/mach-iop13xx/msi.c
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index 000000000000..2d2369302220
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+++ b/arch/arm/mach-iop13xx/msi.c
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+/*
+ * 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 inline u32 read_imipr_0(void)
+{
+ u32 val;
+ asm volatile("mrc p6, 0, %0, c8, c1, 0":"=r" (val));
+ return val;
+}
+static inline void write_imipr_0(u32 val)
+{
+ asm volatile("mcr p6, 0, %0, c8, c1, 0"::"r" (val));
+}
+
+/* IMIPR1 CP6 R9 Page 1
+ */
+static inline u32 read_imipr_1(void)
+{
+ u32 val;
+ asm volatile("mrc p6, 0, %0, c9, c1, 0":"=r" (val));
+ return val;
+}
+static inline void write_imipr_1(u32 val)
+{
+ asm volatile("mcr p6, 0, %0, c9, c1, 0"::"r" (val));
+}
+
+/* IMIPR2 CP6 R10 Page 1
+ */
+static inline u32 read_imipr_2(void)
+{
+ u32 val;
+ asm volatile("mrc p6, 0, %0, c10, c1, 0":"=r" (val));
+ return val;
+}
+static inline void write_imipr_2(u32 val)
+{
+ asm volatile("mcr p6, 0, %0, c10, c1, 0"::"r" (val));
+}
+
+/* IMIPR3 CP6 R11 Page 1
+ */
+static inline u32 read_imipr_3(void)
+{
+ u32 val;
+ asm volatile("mrc p6, 0, %0, c11, c1, 0":"=r" (val));
+ return val;
+}
+static inline 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 */
+ desc = irq_desc + IRQ_IOP13XX_MSI_0 + j + (32*i);
+ desc_handle_irq(IRQ_IOP13XX_MSI_0 + j + (32*i), desc);
+ 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 irq;
+}
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