// SPDX-License-Identifier: GPL-2.0
/*
 *      linux/arch/alpha/kernel/core_mcpcia.c
 *
 * Based on code written by David A Rusling (david.rusling@reo.mts.dec.com).
 *
 * Code common to all MCbus-PCI Adaptor core logic chipsets
 */

#define __EXTERN_INLINE inline
#include <asm/io.h>
#include <asm/core_mcpcia.h>
#undef __EXTERN_INLINE

#include <linux/types.h>
#include <linux/pci.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/delay.h>

#include <asm/ptrace.h>

#include "proto.h"
#include "pci_impl.h"

/*
 * NOTE: Herein lie back-to-back mb instructions.  They are magic. 
 * One plausible explanation is that the i/o controller does not properly
 * handle the system transaction.  Another involves timing.  Ho hum.
 */

/*
 * BIOS32-style PCI interface:
 */

#define DEBUG_CFG 0

#if DEBUG_CFG
# define DBG_CFG(args)  printk args
#else
# define DBG_CFG(args)
#endif

/*
 * Given a bus, device, and function number, compute resulting
 * configuration space address and setup the MCPCIA_HAXR2 register
 * accordingly.  It is therefore not safe to have concurrent
 * invocations to configuration space access routines, but there
 * really shouldn't be any need for this.
 *
 * Type 0:
 *
 *  3 3|3 3 2 2|2 2 2 2|2 2 2 2|1 1 1 1|1 1 1 1|1 1 
 *  3 2|1 0 9 8|7 6 5 4|3 2 1 0|9 8 7 6|5 4 3 2|1 0 9 8|7 6 5 4|3 2 1 0
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * | | |D|D|D|D|D|D|D|D|D|D|D|D|D|D|D|D|D|D|D|D|D|F|F|F|R|R|R|R|R|R|0|0|
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *      31:11   Device select bit.
 *      10:8    Function number
 *       7:2    Register number
 *
 * Type 1:
 *
 *  3 3|3 3 2 2|2 2 2 2|2 2 2 2|1 1 1 1|1 1 1 1|1 1 
 *  3 2|1 0 9 8|7 6 5 4|3 2 1 0|9 8 7 6|5 4 3 2|1 0 9 8|7 6 5 4|3 2 1 0
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * | | | | | | | | | | |B|B|B|B|B|B|B|B|D|D|D|D|D|F|F|F|R|R|R|R|R|R|0|1|
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *      31:24   reserved
 *      23:16   bus number (8 bits = 128 possible buses)
 *      15:11   Device number (5 bits)
 *      10:8    function number
 *       7:2    register number
 *  
 * Notes:
 *      The function number selects which function of a multi-function device 
 *      (e.g., SCSI and Ethernet).
 * 
 *      The register selects a DWORD (32 bit) register offset.  Hence it
 *      doesn't get shifted by 2 bits as we want to "drop" the bottom two
 *      bits.
 */

static unsigned int
conf_read(unsigned long addr, unsigned char type1,
          struct pci_controller *hose)
{
        unsigned long flags;
        unsigned long mid = MCPCIA_HOSE2MID(hose->index);
        unsigned int stat0, value, cpu;

        cpu = smp_processor_id();

        local_irq_save(flags);

        DBG_CFG(("conf_read(addr=0x%lx, type1=%d, hose=%d)\n",
                 addr, type1, mid));

        /* Reset status register to avoid losing errors.  */
        stat0 = *(vuip)MCPCIA_CAP_ERR(mid);
        *(vuip)MCPCIA_CAP_ERR(mid) = stat0;
        mb();
        *(vuip)MCPCIA_CAP_ERR(mid);
        DBG_CFG(("conf_read: MCPCIA_CAP_ERR(%d) was 0x%x\n", mid, stat0));

        mb();
        draina();
        mcheck_expected(cpu) = 1;
        mcheck_taken(cpu) = 0;
        mcheck_extra(cpu) = mid;
        mb();

        /* Access configuration space.  */
        value = *((vuip)addr);
        mb();
        mb();  /* magic */

        if (mcheck_taken(cpu)) {
                mcheck_taken(cpu) = 0;
                value = 0xffffffffU;
                mb();
        }
        mcheck_expected(cpu) = 0;
        mb();

        DBG_CFG(("conf_read(): finished\n"));

        local_irq_restore(flags);
        return value;
}

static void
conf_write(unsigned long addr, unsigned int value, unsigned char type1,
           struct pci_controller *hose)
{
        unsigned long flags;
        unsigned long mid = MCPCIA_HOSE2MID(hose->index);
        unsigned int stat0, cpu;

        cpu = smp_processor_id();

        local_irq_save(flags);  /* avoid getting hit by machine check */

        /* Reset status register to avoid losing errors.  */
        stat0 = *(vuip)MCPCIA_CAP_ERR(mid);
        *(vuip)MCPCIA_CAP_ERR(mid) = stat0; mb();
        *(vuip)MCPCIA_CAP_ERR(mid);
        DBG_CFG(("conf_write: MCPCIA CAP_ERR(%d) was 0x%x\n", mid, stat0));

        draina();
        mcheck_expected(cpu) = 1;
        mcheck_extra(cpu) = mid;
        mb();

        /* Access configuration space.  */
        *((vuip)addr) = value;
        mb();
        mb();  /* magic */
        *(vuip)MCPCIA_CAP_ERR(mid); /* read to force the write */
        mcheck_expected(cpu) = 0;
        mb();

        DBG_CFG(("conf_write(): finished\n"));
        local_irq_restore(flags);
}

static int
mk_conf_addr(struct pci_bus *pbus, unsigned int devfn, int where,
             struct pci_controller *hose, unsigned long *pci_addr,
             unsigned char *type1)
{
        u8 bus = pbus->number;
        unsigned long addr;

        DBG_CFG(("mk_conf_addr(bus=%d,devfn=0x%x,hose=%d,where=0x%x,"
                 " pci_addr=0x%p, type1=0x%p)\n",
                 bus, devfn, hose->index, where, pci_addr, type1));

        /* Type 1 configuration cycle for *ALL* busses.  */
        *type1 = 1;

        if (!pbus->parent) /* No parent means peer PCI bus. */
                bus = 0;
        addr = (bus << 16) | (devfn << 8) | (where);
        addr <<= 5; /* swizzle for SPARSE */
        addr |= hose->config_space_base;

        *pci_addr = addr;
        DBG_CFG(("mk_conf_addr: returning pci_addr 0x%lx\n", addr));
        return 0;
}

static int
mcpcia_read_config(struct pci_bus *bus, unsigned int devfn, int where,
                   int size, u32 *value)
{
        struct pci_controller *hose = bus->sysdata;
        unsigned long addr, w;
        unsigned char type1;

        if (mk_conf_addr(bus, devfn, where, hose, &addr, &type1))
                return PCIBIOS_DEVICE_NOT_FOUND;

        addr |= (size - 1) * 8;
        w = conf_read(addr, type1, hose);
        switch (size) {
        case 1:
                *value = __kernel_extbl(w, where & 3);
                break;
        case 2:
                *value = __kernel_extwl(w, where & 3);
                break;
        case 4:
                *value = w;
                break;
        }
        return PCIBIOS_SUCCESSFUL;
}

static int
mcpcia_write_config(struct pci_bus *bus, unsigned int devfn, int where,
                    int size, u32 value)
{
        struct pci_controller *hose = bus->sysdata;
        unsigned long addr;
        unsigned char type1;

        if (mk_conf_addr(bus, devfn, where, hose, &addr, &type1))
                return PCIBIOS_DEVICE_NOT_FOUND;

        addr |= (size - 1) * 8;
        value = __kernel_insql(value, where & 3);
        conf_write(addr, value, type1, hose);
        return PCIBIOS_SUCCESSFUL;
}

struct pci_ops mcpcia_pci_ops = 
{
        .read =         mcpcia_read_config,
        .write =        mcpcia_write_config,
};

void
mcpcia_pci_tbi(struct pci_controller *hose, dma_addr_t start, dma_addr_t end)
{
        wmb();
        *(vuip)MCPCIA_SG_TBIA(MCPCIA_HOSE2MID(hose->index)) = 0;
        mb();
}

static int __init
mcpcia_probe_hose(int h)
{
        int cpu = smp_processor_id();
        int mid = MCPCIA_HOSE2MID(h);
        unsigned int pci_rev;

        /* Gotta be REAL careful.  If hose is absent, we get an mcheck.  */

        mb();
        mb();
        draina();
        wrmces(7);

        mcheck_expected(cpu) = 2;       /* indicates probing */
        mcheck_taken(cpu) = 0;
        mcheck_extra(cpu) = mid;
        mb();

        /* Access the bus revision word. */
        pci_rev = *(vuip)MCPCIA_REV(mid);

        mb();
        mb();  /* magic */
        if (mcheck_taken(cpu)) {
                mcheck_taken(cpu) = 0;
                pci_rev = 0xffffffff;
                mb();
        }
        mcheck_expected(cpu) = 0;
        mb();

        return (pci_rev >> 16) == PCI_CLASS_BRIDGE_HOST;
}

static void __init
mcpcia_new_hose(int h)
{
        struct pci_controller *hose;
        struct resource *io, *mem, *hae_mem;
        int mid = MCPCIA_HOSE2MID(h);

        hose = alloc_pci_controller();
        if (h == 0)
                pci_isa_hose = hose;
        io = alloc_resource();
        mem = alloc_resource();
        hae_mem = alloc_resource();
                        
        hose->io_space = io;
        hose->mem_space = hae_mem;
        hose->sparse_mem_base = MCPCIA_SPARSE(mid) - IDENT_ADDR;
        hose->dense_mem_base = MCPCIA_DENSE(mid) - IDENT_ADDR;
        hose->sparse_io_base = MCPCIA_IO(mid) - IDENT_ADDR;
        hose->dense_io_base = 0;
        hose->config_space_base = MCPCIA_CONF(mid);
        hose->index = h;

        io->start = MCPCIA_IO(mid) - MCPCIA_IO_BIAS;
        io->end = io->start + 0xffff;
        io->name = pci_io_names[h];
        io->flags = IORESOURCE_IO;

        mem->start = MCPCIA_DENSE(mid) - MCPCIA_MEM_BIAS;
        mem->end = mem->start + 0xffffffff;
        mem->name = pci_mem_names[h];
        mem->flags = IORESOURCE_MEM;

        hae_mem->start = mem->start;
        hae_mem->end = mem->start + MCPCIA_MEM_MASK;
        hae_mem->name = pci_hae0_name;
        hae_mem->flags = IORESOURCE_MEM;

        if (request_resource(&ioport_resource, io) < 0)
                printk(KERN_ERR "Failed to request IO on hose %d\n", h);
        if (request_resource(&iomem_resource, mem) < 0)
                printk(KERN_ERR "Failed to request MEM on hose %d\n", h);
        if (request_resource(mem, hae_mem) < 0)
                printk(KERN_ERR "Failed to request HAE_MEM on hose %d\n", h);
}

static void
mcpcia_pci_clr_err(int mid)
{
        *(vuip)MCPCIA_CAP_ERR(mid);
        *(vuip)MCPCIA_CAP_ERR(mid) = 0xffffffff;   /* Clear them all.  */
        mb();
        *(vuip)MCPCIA_CAP_ERR(mid);  /* Re-read for force write.  */
}

static void __init
mcpcia_startup_hose(struct pci_controller *hose)
{
        int mid = MCPCIA_HOSE2MID(hose->index);
        unsigned int tmp;

        mcpcia_pci_clr_err(mid);

        /* 
         * Set up error reporting.
         */
        tmp = *(vuip)MCPCIA_CAP_ERR(mid);
        tmp |= 0x0006;          /* master/target abort */
        *(vuip)MCPCIA_CAP_ERR(mid) = tmp;
        mb();
        tmp = *(vuip)MCPCIA_CAP_ERR(mid);

        /*
         * Set up the PCI->physical memory translation windows.
         *
         * Window 0 is scatter-gather 8MB at 8MB (for isa)
         * Window 1 is scatter-gather (up to) 1GB at 1GB (for pci)
         * Window 2 is direct access 2GB at 2GB
         */
        hose->sg_isa = iommu_arena_new(hose, 0x00800000, 0x00800000,
                                       SMP_CACHE_BYTES);
        hose->sg_pci = iommu_arena_new(hose, 0x40000000,
                                       size_for_memory(0x40000000),
                                       SMP_CACHE_BYTES);

        __direct_map_base = 0x80000000;
        __direct_map_size = 0x80000000;

        *(vuip)MCPCIA_W0_BASE(mid) = hose->sg_isa->dma_base | 3;
        *(vuip)MCPCIA_W0_MASK(mid) = (hose->sg_isa->size - 1) & 0xfff00000;
        *(vuip)MCPCIA_T0_BASE(mid) = virt_to_phys(hose->sg_isa->ptes) >> 8;

        *(vuip)MCPCIA_W1_BASE(mid) = hose->sg_pci->dma_base | 3;
        *(vuip)MCPCIA_W1_MASK(mid) = (hose->sg_pci->size - 1) & 0xfff00000;
        *(vuip)MCPCIA_T1_BASE(mid) = virt_to_phys(hose->sg_pci->ptes) >> 8;

        *(vuip)MCPCIA_W2_BASE(mid) = __direct_map_base | 1;
        *(vuip)MCPCIA_W2_MASK(mid) = (__direct_map_size - 1) & 0xfff00000;
        *(vuip)MCPCIA_T2_BASE(mid) = 0;

        *(vuip)MCPCIA_W3_BASE(mid) = 0x0;

        mcpcia_pci_tbi(hose, 0, -1);

        *(vuip)MCPCIA_HBASE(mid) = 0x0;
        mb();

        *(vuip)MCPCIA_HAE_MEM(mid) = 0U;
        mb();
        *(vuip)MCPCIA_HAE_MEM(mid); /* read it back. */
        *(vuip)MCPCIA_HAE_IO(mid) = 0;
        mb();
        *(vuip)MCPCIA_HAE_IO(mid);  /* read it back. */
}

void __init
mcpcia_init_arch(void)
{
        /* With multiple PCI busses, we play with I/O as physical addrs.  */
        ioport_resource.end = ~0UL;

        /* Allocate hose 0.  That's the one that all the ISA junk hangs
           off of, from which we'll be registering stuff here in a bit.
           Other hose detection is done in mcpcia_init_hoses, which is
           called from init_IRQ.  */

        mcpcia_new_hose(0);
}

/* This is called from init_IRQ, since we cannot take interrupts
   before then.  Which means we cannot do this in init_arch.  */

void __init
mcpcia_init_hoses(void)
{
        struct pci_controller *hose;
        int hose_count;
        int h;

        /* First, find how many hoses we have.  */
        hose_count = 0;
        for (h = 0; h < MCPCIA_MAX_HOSES; ++h) {
                if (mcpcia_probe_hose(h)) {
                        if (h != 0)
                                mcpcia_new_hose(h);
                        hose_count++;
                }
        }

        printk("mcpcia_init_hoses: found %d hoses\n", hose_count);

        /* Now do init for each hose.  */
        for (hose = hose_head; hose; hose = hose->next)
                mcpcia_startup_hose(hose);
}

static void
mcpcia_print_uncorrectable(struct el_MCPCIA_uncorrected_frame_mcheck *logout)
{
        struct el_common_EV5_uncorrectable_mcheck *frame;
        int i;

        frame = &logout->procdata;

        /* Print PAL fields */
        for (i = 0; i < 24; i += 2) {
                printk("  paltmp[%d-%d] = %16lx %16lx\n",
                       i, i+1, frame->paltemp[i], frame->paltemp[i+1]);
        }
        for (i = 0; i < 8; i += 2) {
                printk("  shadow[%d-%d] = %16lx %16lx\n",
                       i, i+1, frame->shadow[i], 
                       frame->shadow[i+1]);
        }
        printk("  Addr of excepting instruction  = %16lx\n",
               frame->exc_addr);
        printk("  Summary of arithmetic traps    = %16lx\n",
               frame->exc_sum);
        printk("  Exception mask                 = %16lx\n",
               frame->exc_mask);
        printk("  Base address for PALcode       = %16lx\n",
               frame->pal_base);
        printk("  Interrupt Status Reg           = %16lx\n",
               frame->isr);
        printk("  CURRENT SETUP OF EV5 IBOX      = %16lx\n",
               frame->icsr);
        printk("  I-CACHE Reg %s parity error   = %16lx\n",
               (frame->ic_perr_stat & 0x800L) ? 
               "Data" : "Tag", 
               frame->ic_perr_stat); 
        printk("  D-CACHE error Reg              = %16lx\n",
               frame->dc_perr_stat);
        if (frame->dc_perr_stat & 0x2) {
                switch (frame->dc_perr_stat & 0x03c) {
                case 8:
                        printk("    Data error in bank 1\n");
                        break;
                case 4:
                        printk("    Data error in bank 0\n");
                        break;
                case 20:
                        printk("    Tag error in bank 1\n");
                        break;
                case 10:
                        printk("    Tag error in bank 0\n");
                        break;
                }
        }
        printk("  Effective VA                   = %16lx\n",
               frame->va);
        printk("  Reason for D-stream            = %16lx\n",
               frame->mm_stat);
        printk("  EV5 SCache address             = %16lx\n",
               frame->sc_addr);
        printk("  EV5 SCache TAG/Data parity     = %16lx\n",
               frame->sc_stat);
        printk("  EV5 BC_TAG_ADDR                = %16lx\n",
               frame->bc_tag_addr);
        printk("  EV5 EI_ADDR: Phys addr of Xfer = %16lx\n",
               frame->ei_addr);
        printk("  Fill Syndrome                  = %16lx\n",
               frame->fill_syndrome);
        printk("  EI_STAT reg                    = %16lx\n",
               frame->ei_stat);
        printk("  LD_LOCK                        = %16lx\n",
               frame->ld_lock);
}

static void
mcpcia_print_system_area(unsigned long la_ptr)
{
        struct el_common *frame;
        struct pci_controller *hose;

        struct IOD_subpacket {
          unsigned long base;
          unsigned int whoami;
          unsigned int rsvd1;
          unsigned int pci_rev;
          unsigned int cap_ctrl;
          unsigned int hae_mem;
          unsigned int hae_io;
          unsigned int int_ctl;
          unsigned int int_reg;
          unsigned int int_mask0;
          unsigned int int_mask1;
          unsigned int mc_err0;
          unsigned int mc_err1;
          unsigned int cap_err;
          unsigned int rsvd2;
          unsigned int pci_err1;
          unsigned int mdpa_stat;
          unsigned int mdpa_syn;
          unsigned int mdpb_stat;
          unsigned int mdpb_syn;
          unsigned int rsvd3;
          unsigned int rsvd4;
          unsigned int rsvd5;
        } *iodpp;

        frame = (struct el_common *)la_ptr;
        iodpp = (struct IOD_subpacket *) (la_ptr + frame->sys_offset);

        for (hose = hose_head; hose; hose = hose->next, iodpp++) {

          printk("IOD %d Register Subpacket - Bridge Base Address %16lx\n",
                 hose->index, iodpp->base);
          printk("  WHOAMI      = %8x\n", iodpp->whoami);
          printk("  PCI_REV     = %8x\n", iodpp->pci_rev);
          printk("  CAP_CTRL    = %8x\n", iodpp->cap_ctrl);
          printk("  HAE_MEM     = %8x\n", iodpp->hae_mem);
          printk("  HAE_IO      = %8x\n", iodpp->hae_io);
          printk("  INT_CTL     = %8x\n", iodpp->int_ctl);
          printk("  INT_REG     = %8x\n", iodpp->int_reg);
          printk("  INT_MASK0   = %8x\n", iodpp->int_mask0);
          printk("  INT_MASK1   = %8x\n", iodpp->int_mask1);
          printk("  MC_ERR0     = %8x\n", iodpp->mc_err0);
          printk("  MC_ERR1     = %8x\n", iodpp->mc_err1);
          printk("  CAP_ERR     = %8x\n", iodpp->cap_err);
          printk("  PCI_ERR1    = %8x\n", iodpp->pci_err1);
          printk("  MDPA_STAT   = %8x\n", iodpp->mdpa_stat);
          printk("  MDPA_SYN    = %8x\n", iodpp->mdpa_syn);
          printk("  MDPB_STAT   = %8x\n", iodpp->mdpb_stat);
          printk("  MDPB_SYN    = %8x\n", iodpp->mdpb_syn);
        }
}

void
mcpcia_machine_check(unsigned long vector, unsigned long la_ptr)
{
        struct el_MCPCIA_uncorrected_frame_mcheck *mchk_logout;
        unsigned int cpu = smp_processor_id();
        int expected;

        mchk_logout = (struct el_MCPCIA_uncorrected_frame_mcheck *)la_ptr;
        expected = mcheck_expected(cpu);

        mb();
        mb();  /* magic */
        draina();

        switch (expected) {
        case 0:
            {
                /* FIXME: how do we figure out which hose the
                   error was on?  */    
                struct pci_controller *hose;
                for (hose = hose_head; hose; hose = hose->next)
                        mcpcia_pci_clr_err(MCPCIA_HOSE2MID(hose->index));
                break;
            }
        case 1:
                mcpcia_pci_clr_err(mcheck_extra(cpu));
                break;
        default:
                /* Otherwise, we're being called from mcpcia_probe_hose
                   and there's no hose clear an error from.  */
                break;
        }

        wrmces(0x7);
        mb();

        process_mcheck_info(vector, la_ptr, "MCPCIA", expected != 0);
        if (!expected && vector != 0x620 && vector != 0x630) {
                mcpcia_print_uncorrectable(mchk_logout);
                mcpcia_print_system_area(la_ptr);
        }
}