arch/powerpc/platforms/52xx/media5200.c

   1 /*
   2  * Support for 'media5200-platform' compatible boards.
   3  *
   4  * Copyright (C) 2008 Secret Lab Technologies Ltd.
   5  *
   6  * This program is free software; you can redistribute  it and/or modify it
   7  * under  the terms of  the GNU General  Public License as published by the
   8  * Free Software Foundation;  either version 2 of the  License, or (at your
   9  * option) any later version.
  10  *
  11  * Description:
  12  * This code implements support for the Freescape Media5200 platform
  13  * (built around the MPC5200 SoC).
  14  *
  15  * Notable characteristic of the Media5200 is the presence of an FPGA
  16  * that has all external IRQ lines routed through it.  This file implements
  17  * a cascaded interrupt controller driver which attaches itself to the
  18  * Virtual IRQ subsystem after the primary mpc5200 interrupt controller
  19  * is initialized.
  20  *
  21  */
  22
  23 #undef DEBUG
  24
  25 #include <linux/irq.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/io.h>
  28 #include <asm/time.h>
  29 #include <asm/prom.h>
  30 #include <asm/machdep.h>
  31 #include <asm/mpc52xx.h>
  32
  33 static struct of_device_id mpc5200_gpio_ids[] __initdata = {
  34         { .compatible = "fsl,mpc5200-gpio", },
  35         { .compatible = "mpc5200-gpio", },
  36         {}
  37 };
  38
  39 /* FPGA register set */
  40 #define MEDIA5200_IRQ_ENABLE (0x40c)
  41 #define MEDIA5200_IRQ_STATUS (0x410)
  42 #define MEDIA5200_NUM_IRQS   (6)
  43 #define MEDIA5200_IRQ_SHIFT  (32 - MEDIA5200_NUM_IRQS)
  44
  45 struct media5200_irq {
  46         void __iomem *regs;
  47         spinlock_t lock;
  48         struct irq_host *irqhost;
  49 };
  50 struct media5200_irq media5200_irq;
  51
  52 static void media5200_irq_unmask(struct irq_data *d)
  53 {
  54         unsigned long flags;
  55         u32 val;
  56
  57         spin_lock_irqsave(&media5200_irq.lock, flags);
  58         val = in_be32(media5200_irq.regs + MEDIA5200_IRQ_ENABLE);
  59         val |= 1 << (MEDIA5200_IRQ_SHIFT + irq_map[d->irq].hwirq);
  60         out_be32(media5200_irq.regs + MEDIA5200_IRQ_ENABLE, val);
  61         spin_unlock_irqrestore(&media5200_irq.lock, flags);
  62 }
  63
  64 static void media5200_irq_mask(struct irq_data *d)
  65 {
  66         unsigned long flags;
  67         u32 val;
  68
  69         spin_lock_irqsave(&media5200_irq.lock, flags);
  70         val = in_be32(media5200_irq.regs + MEDIA5200_IRQ_ENABLE);
  71         val &= ~(1 << (MEDIA5200_IRQ_SHIFT + irq_map[d->irq].hwirq));
  72         out_be32(media5200_irq.regs + MEDIA5200_IRQ_ENABLE, val);
  73         spin_unlock_irqrestore(&media5200_irq.lock, flags);
  74 }
  75
  76 static struct irq_chip media5200_irq_chip = {
  77         .name = "Media5200 FPGA",
  78         .irq_unmask = media5200_irq_unmask,
  79         .irq_mask = media5200_irq_mask,
  80         .irq_mask_ack = media5200_irq_mask,
  81 };
  82
  83 void media5200_irq_cascade(unsigned int virq, struct irq_desc *desc)
  84 {
  85         struct irq_chip *chip = get_irq_desc_chip(desc);
  86         int sub_virq, val;
  87         u32 status, enable;
  88
  89         /* Mask off the cascaded IRQ */
  90         raw_spin_lock(&desc->lock);
  91         chip->irq_mask(&desc->irq_data);
  92         raw_spin_unlock(&desc->lock);
  93
  94         /* Ask the FPGA for IRQ status.  If 'val' is 0, then no irqs
  95          * are pending.  'ffs()' is 1 based */
  96         status = in_be32(media5200_irq.regs + MEDIA5200_IRQ_ENABLE);
  97         enable = in_be32(media5200_irq.regs + MEDIA5200_IRQ_STATUS);
  98         val = ffs((status & enable) >> MEDIA5200_IRQ_SHIFT);
  99         if (val) {
 100                 sub_virq = irq_linear_revmap(media5200_irq.irqhost, val - 1);
 101                 /* pr_debug("%s: virq=%i s=%.8x e=%.8x hwirq=%i subvirq=%i\n",
 102                  *          __func__, virq, status, enable, val - 1, sub_virq);
 103                  */
 104                 generic_handle_irq(sub_virq);
 105         }
 106
 107         /* Processing done; can reenable the cascade now */
 108         raw_spin_lock(&desc->lock);
 109         chip->irq_ack(&desc->irq_data);
 110         if (!irqd_irq_disabled(&desc->irq_data))
 111                 chip->irq_unmask(&desc->irq_data);
 112         raw_spin_unlock(&desc->lock);
 113 }
 114
 115 static int media5200_irq_map(struct irq_host *h, unsigned int virq,
 116                              irq_hw_number_t hw)
 117 {
 118         pr_debug("%s: h=%p, virq=%i, hwirq=%i\n", __func__, h, virq, (int)hw);
 119         set_irq_chip_data(virq, &media5200_irq);
 120         set_irq_chip_and_handler(virq, &media5200_irq_chip, handle_level_irq);
 121         irq_set_status_flags(virq, IRQ_LEVEL);
 122         return 0;
 123 }
 124
 125 static int media5200_irq_xlate(struct irq_host *h, struct device_node *ct,
 126                                  const u32 *intspec, unsigned int intsize,
 127                                  irq_hw_number_t *out_hwirq,
 128                                  unsigned int *out_flags)
 129 {
 130         if (intsize != 2)
 131                 return -1;
 132
 133         pr_debug("%s: bank=%i, number=%i\n", __func__, intspec[0], intspec[1]);
 134         *out_hwirq = intspec[1];
 135         *out_flags = IRQ_TYPE_NONE;
 136         return 0;
 137 }
 138
 139 static struct irq_host_ops media5200_irq_ops = {
 140         .map = media5200_irq_map,
 141         .xlate = media5200_irq_xlate,
 142 };
 143
 144 /*
 145  * Setup Media5200 IRQ mapping
 146  */
 147 static void __init media5200_init_irq(void)
 148 {
 149         struct device_node *fpga_np;
 150         int cascade_virq;
 151
 152         /* First setup the regular MPC5200 interrupt controller */
 153         mpc52xx_init_irq();
 154
 155         /* Now find the FPGA IRQ */
 156         fpga_np = of_find_compatible_node(NULL, NULL, "fsl,media5200-fpga");
 157         if (!fpga_np)
 158                 goto out;
 159         pr_debug("%s: found fpga node: %s\n", __func__, fpga_np->full_name);
 160
 161         media5200_irq.regs = of_iomap(fpga_np, 0);
 162         if (!media5200_irq.regs)
 163                 goto out;
 164         pr_debug("%s: mapped to %p\n", __func__, media5200_irq.regs);
 165
 166         cascade_virq = irq_of_parse_and_map(fpga_np, 0);
 167         if (!cascade_virq)
 168                 goto out;
 169         pr_debug("%s: cascaded on virq=%i\n", __func__, cascade_virq);
 170
 171         /* Disable all FPGA IRQs */
 172         out_be32(media5200_irq.regs + MEDIA5200_IRQ_ENABLE, 0);
 173
 174         spin_lock_init(&media5200_irq.lock);
 175
 176         media5200_irq.irqhost = irq_alloc_host(fpga_np, IRQ_HOST_MAP_LINEAR,
 177                                                MEDIA5200_NUM_IRQS,
 178                                                &media5200_irq_ops, -1);
 179         if (!media5200_irq.irqhost)
 180                 goto out;
 181         pr_debug("%s: allocated irqhost\n", __func__);
 182
 183         media5200_irq.irqhost->host_data = &media5200_irq;
 184
 185         set_irq_data(cascade_virq, &media5200_irq);
 186         set_irq_chained_handler(cascade_virq, media5200_irq_cascade);
 187
 188         return;
 189
 190  out:
 191         pr_err("Could not find Media5200 FPGA; PCI interrupts will not work\n");
 192 }
 193
 194 /*
 195  * Setup the architecture
 196  */
 197 static void __init media5200_setup_arch(void)
 198 {
 199
 200         struct device_node *np;
 201         struct mpc52xx_gpio __iomem *gpio;
 202         u32 port_config;
 203
 204         if (ppc_md.progress)
 205                 ppc_md.progress("media5200_setup_arch()", 0);
 206
 207         /* Map important registers from the internal memory map */
 208         mpc52xx_map_common_devices();
 209
 210         /* Some mpc5200 & mpc5200b related configuration */
 211         mpc5200_setup_xlb_arbiter();
 212
 213         mpc52xx_setup_pci();
 214
 215         np = of_find_matching_node(NULL, mpc5200_gpio_ids);
 216         gpio = of_iomap(np, 0);
 217         of_node_put(np);
 218         if (!gpio) {
 219                 printk(KERN_ERR "%s() failed. expect abnormal behavior\n",
 220                        __func__);
 221                 return;
 222         }
 223
 224         /* Set port config */
 225         port_config = in_be32(&gpio->port_config);
 226
 227         port_config &= ~0x03000000;     /* ATA CS is on csb_4/5         */
 228         port_config |=  0x01000000;
 229
 230         out_be32(&gpio->port_config, port_config);
 231
 232         /* Unmap zone */
 233         iounmap(gpio);
 234
 235 }
 236
 237 /* list of the supported boards */
 238 static const char *board[] __initdata = {
 239         "fsl,media5200",
 240         NULL
 241 };
 242
 243 /*
 244  * Called very early, MMU is off, device-tree isn't unflattened
 245  */
 246 static int __init media5200_probe(void)
 247 {
 248         return of_flat_dt_match(of_get_flat_dt_root(), board);
 249 }
 250
 251 define_machine(media5200_platform) {
 252         .name           = "media5200-platform",
 253         .probe          = media5200_probe,
 254         .setup_arch     = media5200_setup_arch,
 255         .init           = mpc52xx_declare_of_platform_devices,
 256         .init_IRQ       = media5200_init_irq,
 257         .get_irq        = mpc52xx_get_irq,
 258         .restart        = mpc52xx_restart,
 259         .calibrate_decr = generic_calibrate_decr,
 260 };