LXR linux/arch/powerpc/sysdev/tsi108

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Common routines for Tundra Semiconductor TSI108 host bridge.
   4 *
   5 * 2004-2005 (c) Tundra Semiconductor Corp.
   6 * Author: Alex Bounine (alexandreb@tundra.com)
   7 * Author: Roy Zang (tie-fei.zang@freescale.com)
   8 *         Add pci interrupt router host
   9 */
  10
  11#include <linux/kernel.h>
  12#include <linux/init.h>
  13#include <linux/pci.h>
  14#include <linux/irq.h>
  15#include <linux/interrupt.h>
  16
  17#include <asm/byteorder.h>
  18#include <asm/io.h>
  19#include <asm/irq.h>
  20#include <linux/uaccess.h>
  21#include <asm/machdep.h>
  22#include <asm/pci-bridge.h>
  23#include <asm/tsi108.h>
  24#include <asm/tsi108_pci.h>
  25#include <asm/tsi108_irq.h>
  26#include <asm/prom.h>
  27
  28#undef DEBUG
  29#ifdef DEBUG
  30#define DBG(x...) printk(x)
  31#else
  32#define DBG(x...)
  33#endif
  34
  35#define tsi_mk_config_addr(bus, devfunc, offset) \
  36        ((((bus)<<16) | ((devfunc)<<8) | (offset & 0xfc)) + tsi108_pci_cfg_base)
  37
  38u32 tsi108_pci_cfg_base;
  39static u32 tsi108_pci_cfg_phys;
  40u32 tsi108_csr_vir_base;
  41static struct irq_domain *pci_irq_host;
  42
  43extern u32 get_vir_csrbase(void);
  44extern u32 tsi108_read_reg(u32 reg_offset);
  45extern void tsi108_write_reg(u32 reg_offset, u32 val);
  46
  47int
  48tsi108_direct_write_config(struct pci_bus *bus, unsigned int devfunc,
  49                           int offset, int len, u32 val)
  50{
  51        volatile unsigned char *cfg_addr;
  52        struct pci_controller *hose = pci_bus_to_host(bus);
  53
  54        if (ppc_md.pci_exclude_device)
  55                if (ppc_md.pci_exclude_device(hose, bus->number, devfunc))
  56                        return PCIBIOS_DEVICE_NOT_FOUND;
  57
  58        cfg_addr = (unsigned char *)(tsi_mk_config_addr(bus->number,
  59                                                        devfunc, offset) |
  60                                                        (offset & 0x03));
  61
  62#ifdef DEBUG
  63        printk("PCI CFG write : ");
  64        printk("%d:0x%x:0x%x ", bus->number, devfunc, offset);
  65        printk("%d ADDR=0x%08x ", len, (uint) cfg_addr);
  66        printk("data = 0x%08x\n", val);
  67#endif
  68
  69        switch (len) {
  70        case 1:
  71                out_8((u8 *) cfg_addr, val);
  72                break;
  73        case 2:
  74                out_le16((u16 *) cfg_addr, val);
  75                break;
  76        default:
  77                out_le32((u32 *) cfg_addr, val);
  78                break;
  79        }
  80
  81        return PCIBIOS_SUCCESSFUL;
  82}
  83
  84void tsi108_clear_pci_error(u32 pci_cfg_base)
  85{
  86        u32 err_stat, err_addr, pci_stat;
  87
  88        /*
  89         * Quietly clear PB and PCI error flags set as result
  90         * of PCI/X configuration read requests.
  91         */
  92
  93        /* Read PB Error Log Registers */
  94
  95        err_stat = tsi108_read_reg(TSI108_PB_OFFSET + TSI108_PB_ERRCS);
  96        err_addr = tsi108_read_reg(TSI108_PB_OFFSET + TSI108_PB_AERR);
  97
  98        if (err_stat & TSI108_PB_ERRCS_ES) {
  99                /* Clear error flag */
 100                tsi108_write_reg(TSI108_PB_OFFSET + TSI108_PB_ERRCS,
 101                                 TSI108_PB_ERRCS_ES);
 102
 103                /* Clear read error reported in PB_ISR */
 104                tsi108_write_reg(TSI108_PB_OFFSET + TSI108_PB_ISR,
 105                                 TSI108_PB_ISR_PBS_RD_ERR);
 106
 107                /* Clear PCI/X bus cfg errors if applicable */
 108                if ((err_addr & 0xFF000000) == pci_cfg_base) {
 109                        pci_stat =
 110                            tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_CSR);
 111                        tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_CSR,
 112                                         pci_stat);
 113                }
 114        }
 115
 116        return;
 117}
 118
 119#define __tsi108_read_pci_config(x, addr, op)           \
 120        __asm__ __volatile__(                           \
 121                "       "op" %0,0,%1\n"         \
 122                "1:     eieio\n"                        \
 123                "2:\n"                                  \
 124                ".section .fixup,\"ax\"\n"              \
 125                "3:     li %0,-1\n"                     \
 126                "       b 2b\n"                         \
 127                ".previous\n"                           \
 128                EX_TABLE(1b, 3b)                        \
 129                : "=r"(x) : "r"(addr))
 130
 131int
 132tsi108_direct_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
 133                          int len, u32 * val)
 134{
 135        volatile unsigned char *cfg_addr;
 136        struct pci_controller *hose = pci_bus_to_host(bus);
 137        u32 temp;
 138
 139        if (ppc_md.pci_exclude_device)
 140                if (ppc_md.pci_exclude_device(hose, bus->number, devfn))
 141                        return PCIBIOS_DEVICE_NOT_FOUND;
 142
 143        cfg_addr = (unsigned char *)(tsi_mk_config_addr(bus->number,
 144                                                        devfn,
 145                                                        offset) | (offset &
 146                                                                   0x03));
 147
 148        switch (len) {
 149        case 1:
 150                __tsi108_read_pci_config(temp, cfg_addr, "lbzx");
 151                break;
 152        case 2:
 153                __tsi108_read_pci_config(temp, cfg_addr, "lhbrx");
 154                break;
 155        default:
 156                __tsi108_read_pci_config(temp, cfg_addr, "lwbrx");
 157                break;
 158        }
 159
 160        *val = temp;
 161
 162#ifdef DEBUG
 163        if ((0xFFFFFFFF != temp) && (0xFFFF != temp) && (0xFF != temp)) {
 164                printk("PCI CFG read : ");
 165                printk("%d:0x%x:0x%x ", bus->number, devfn, offset);
 166                printk("%d ADDR=0x%08x ", len, (uint) cfg_addr);
 167                printk("data = 0x%x\n", *val);
 168        }
 169#endif
 170        return PCIBIOS_SUCCESSFUL;
 171}
 172
 173void tsi108_clear_pci_cfg_error(void)
 174{
 175        tsi108_clear_pci_error(tsi108_pci_cfg_phys);
 176}
 177
 178static struct pci_ops tsi108_direct_pci_ops = {
 179        .read = tsi108_direct_read_config,
 180        .write = tsi108_direct_write_config,
 181};
 182
 183int __init tsi108_setup_pci(struct device_node *dev, u32 cfg_phys, int primary)
 184{
 185        int len;
 186        struct pci_controller *hose;
 187        struct resource rsrc;
 188        const int *bus_range;
 189        int has_address = 0;
 190
 191        /* PCI Config mapping */
 192        tsi108_pci_cfg_base = (u32)ioremap(cfg_phys, TSI108_PCI_CFG_SIZE);
 193        tsi108_pci_cfg_phys = cfg_phys;
 194        DBG("TSI_PCI: %s tsi108_pci_cfg_base=0x%x\n", __func__,
 195            tsi108_pci_cfg_base);
 196
 197        /* Fetch host bridge registers address */
 198        has_address = (of_address_to_resource(dev, 0, &rsrc) == 0);
 199
 200        /* Get bus range if any */
 201        bus_range = of_get_property(dev, "bus-range", &len);
 202        if (bus_range == NULL || len < 2 * sizeof(int)) {
 203                printk(KERN_WARNING "Can't get bus-range for %pOF, assume"
 204                       " bus 0\n", dev);
 205        }
 206
 207        hose = pcibios_alloc_controller(dev);
 208
 209        if (!hose) {
 210                printk("PCI Host bridge init failed\n");
 211                return -ENOMEM;
 212        }
 213
 214        hose->first_busno = bus_range ? bus_range[0] : 0;
 215        hose->last_busno = bus_range ? bus_range[1] : 0xff;
 216
 217        (hose)->ops = &tsi108_direct_pci_ops;
 218
 219        printk(KERN_INFO "Found tsi108 PCI host bridge at 0x%08x. "
 220               "Firmware bus number: %d->%d\n",
 221               rsrc.start, hose->first_busno, hose->last_busno);
 222
 223        /* Interpret the "ranges" property */
 224        /* This also maps the I/O region and sets isa_io/mem_base */
 225        pci_process_bridge_OF_ranges(hose, dev, primary);
 226        return 0;
 227}
 228
 229/*
 230 * Low level utility functions
 231 */
 232
 233static void tsi108_pci_int_mask(u_int irq)
 234{
 235        u_int irp_cfg;
 236        int int_line = (irq - IRQ_PCI_INTAD_BASE);
 237
 238        irp_cfg = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL);
 239        mb();
 240        irp_cfg |= (1 << int_line);     /* INTx_DIR = output */
 241        irp_cfg &= ~(3 << (8 + (int_line * 2)));        /* INTx_TYPE = unused */
 242        tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL, irp_cfg);
 243        mb();
 244        irp_cfg = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL);
 245}
 246
 247static void tsi108_pci_int_unmask(u_int irq)
 248{
 249        u_int irp_cfg;
 250        int int_line = (irq - IRQ_PCI_INTAD_BASE);
 251
 252        irp_cfg = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL);
 253        mb();
 254        irp_cfg &= ~(1 << int_line);
 255        irp_cfg |= (3 << (8 + (int_line * 2)));
 256        tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL, irp_cfg);
 257        mb();
 258}
 259
 260static void init_pci_source(void)
 261{
 262        tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL,
 263                        0x0000ff00);
 264        tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE,
 265                        TSI108_PCI_IRP_ENABLE_P_INT);
 266        mb();
 267}
 268
 269static inline unsigned int get_pci_source(void)
 270{
 271        u_int temp = 0;
 272        int irq = -1;
 273        int i;
 274        u_int pci_irp_stat;
 275        static int mask = 0;
 276
 277        /* Read PCI/X block interrupt status register */
 278        pci_irp_stat = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_STAT);
 279        mb();
 280
 281        if (pci_irp_stat & TSI108_PCI_IRP_STAT_P_INT) {
 282                /* Process Interrupt from PCI bus INTA# - INTD# lines */
 283                temp =
 284                    tsi108_read_reg(TSI108_PCI_OFFSET +
 285                                    TSI108_PCI_IRP_INTAD) & 0xf;
 286                mb();
 287                for (i = 0; i < 4; i++, mask++) {
 288                        if (temp & (1 << mask % 4)) {
 289                                irq = IRQ_PCI_INTA + mask % 4;
 290                                mask++;
 291                                break;
 292                        }
 293                }
 294
 295                /* Disable interrupts from PCI block */
 296                temp = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE);
 297                tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE,
 298                                temp & ~TSI108_PCI_IRP_ENABLE_P_INT);
 299                mb();
 300                (void)tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE);
 301                mb();
 302        }
 303#ifdef DEBUG
 304        else {
 305                printk("TSI108_PIC: error in TSI108_PCI_IRP_STAT\n");
 306                pci_irp_stat =
 307                    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_STAT);
 308                temp =
 309                    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_INTAD);
 310                mb();
 311                printk(">> stat=0x%08x intad=0x%08x ", pci_irp_stat, temp);
 312                temp =
 313                    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL);
 314                mb();
 315                printk("cfg_ctl=0x%08x ", temp);
 316                temp =
 317                    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE);
 318                mb();
 319                printk("irp_enable=0x%08x\n", temp);
 320        }
 321#endif  /* end of DEBUG */
 322
 323        return irq;
 324}
 325
 326
 327/*
 328 * Linux descriptor level callbacks
 329 */
 330
 331static void tsi108_pci_irq_unmask(struct irq_data *d)
 332{
 333        tsi108_pci_int_unmask(d->irq);
 334
 335        /* Enable interrupts from PCI block */
 336        tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE,
 337                         tsi108_read_reg(TSI108_PCI_OFFSET +
 338                                         TSI108_PCI_IRP_ENABLE) |
 339                         TSI108_PCI_IRP_ENABLE_P_INT);
 340        mb();
 341}
 342
 343static void tsi108_pci_irq_mask(struct irq_data *d)
 344{
 345        tsi108_pci_int_mask(d->irq);
 346}
 347
 348static void tsi108_pci_irq_ack(struct irq_data *d)
 349{
 350        tsi108_pci_int_mask(d->irq);
 351}
 352
 353/*
 354 * Interrupt controller descriptor for cascaded PCI interrupt controller.
 355 */
 356
 357static struct irq_chip tsi108_pci_irq = {
 358        .name = "tsi108_PCI_int",
 359        .irq_mask = tsi108_pci_irq_mask,
 360        .irq_ack = tsi108_pci_irq_ack,
 361        .irq_unmask = tsi108_pci_irq_unmask,
 362};
 363
 364static int pci_irq_host_xlate(struct irq_domain *h, struct device_node *ct,
 365                            const u32 *intspec, unsigned int intsize,
 366                            irq_hw_number_t *out_hwirq, unsigned int *out_flags)
 367{
 368        *out_hwirq = intspec[0];
 369        *out_flags = IRQ_TYPE_LEVEL_HIGH;
 370        return 0;
 371}
 372
 373static int pci_irq_host_map(struct irq_domain *h, unsigned int virq,
 374                          irq_hw_number_t hw)
 375{       unsigned int irq;
 376        DBG("%s(%d, 0x%lx)\n", __func__, virq, hw);
 377        if ((virq >= 1) && (virq <= 4)){
 378                irq = virq + IRQ_PCI_INTAD_BASE - 1;
 379                irq_set_status_flags(irq, IRQ_LEVEL);
 380                irq_set_chip(irq, &tsi108_pci_irq);
 381        }
 382        return 0;
 383}
 384
 385static const struct irq_domain_ops pci_irq_domain_ops = {
 386        .map = pci_irq_host_map,
 387        .xlate = pci_irq_host_xlate,
 388};
 389
 390/*
 391 * Exported functions
 392 */
 393
 394/*
 395 * The Tsi108 PCI interrupts initialization routine.
 396 *
 397 * The INTA# - INTD# interrupts on the PCI bus are reported by the PCI block
 398 * to the MPIC using single interrupt source (IRQ_TSI108_PCI). Therefore the
 399 * PCI block has to be treated as a cascaded interrupt controller connected
 400 * to the MPIC.
 401 */
 402
 403void __init tsi108_pci_int_init(struct device_node *node)
 404{
 405        DBG("Tsi108_pci_int_init: initializing PCI interrupts\n");
 406
 407        pci_irq_host = irq_domain_add_legacy_isa(node, &pci_irq_domain_ops, NULL);
 408        if (pci_irq_host == NULL) {
 409                printk(KERN_ERR "pci_irq_host: failed to allocate irq domain!\n");
 410                return;
 411        }
 412
 413        init_pci_source();
 414}
 415
 416void tsi108_irq_cascade(struct irq_desc *desc)
 417{
 418        struct irq_chip *chip = irq_desc_get_chip(desc);
 419        unsigned int cascade_irq = get_pci_source();
 420
 421        if (cascade_irq)
 422                generic_handle_irq(cascade_irq);
 423
 424        chip->irq_eoi(&desc->irq_data);
 425}
 426