northbridge.c

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/* SPDX-License-Identifier: GPL-2.0-only */
 
#include <commonlib/helpers.h>
#include <console/console.h>
#include <acpi/acpi.h>
#include <delay.h>
#include <cpu/intel/haswell/haswell.h>
#include <device/device.h>
#include <device/pci.h>
#include <device/pci_def.h>
#include <device/pci_ids.h>
#include <device/pci_ops.h>
#include <boot/tables.h>
#include <security/intel/txt/txt_register.h>
#include <southbridge/intel/lynxpoint/pch.h>
#include <types.h>
 
#include "chip.h"
#include "haswell.h"
 
static const char *northbridge_acpi_name(const struct device *dev)
{
        if (dev->path.type == DEVICE_PATH_DOMAIN)
                return "PCI0";
 
        if (dev->path.type != DEVICE_PATH_PCI || dev->bus->secondary != 0)
                return NULL;
 
        switch (dev->path.pci.devfn) {
        case PCI_DEVFN(0, 0):
                return "MCHC";
        }
 
        return NULL;
}
 
static struct device_operations pci_domain_ops = {
        .read_resources    = pci_domain_read_resources,
        .set_resources     = pci_domain_set_resources,
        .scan_bus          = pci_domain_scan_bus,
        .acpi_name         = northbridge_acpi_name,
        .write_acpi_tables = northbridge_write_acpi_tables,
};
 
static int get_bar(struct device *dev, unsigned int index, u32 *base, u32 *len)
{
        u32 bar = pci_read_config32(dev, index);
 
        /* If not enabled don't report it */
        if (!(bar & 0x1))
                return 0;
 
        /* Knock down the enable bit */
        *base = bar & ~1;
 
        return 1;
}
 
/*
 * There are special BARs that actually are programmed in the MCHBAR. These Intel special
 * features, but they do consume resources that need to be accounted for.
 */
static int get_bar_in_mchbar(struct device *dev, unsigned int index, u32 *base, u32 *len)
{
        u32 bar = mchbar_read32(index);
 
        /* If not enabled don't report it */
        if (!(bar & 0x1))
                return 0;
 
        /* Knock down the enable bit */
        *base = bar & ~1;
 
        return 1;
}
 
struct fixed_mmio_descriptor {
        unsigned int index;
        u32 size;
        int (*get_resource)(struct device *dev, unsigned int index, u32 *base, u32 *size);
        const char *description;
};
 
struct fixed_mmio_descriptor mc_fixed_resources[] = {
        { MCHBAR,   MCH_BASE_SIZE,   get_bar,           "MCHBAR"   },
        { DMIBAR,   DMI_BASE_SIZE,   get_bar,           "DMIBAR"   },
        { EPBAR,    EP_BASE_SIZE,    get_bar,           "EPBAR"    },
        { GDXCBAR,  GDXC_BASE_SIZE,  get_bar_in_mchbar, "GDXCBAR"  },
        { EDRAMBAR, EDRAM_BASE_SIZE, get_bar_in_mchbar, "EDRAMBAR" },
};
 
/* Add all known fixed MMIO ranges that hang off the host bridge/memory controller device. */
static void mc_add_fixed_mmio_resources(struct device *dev)
{
        int i;
 
        for (i = 0; i < ARRAY_SIZE(mc_fixed_resources); i++) {
                u32 base;
                u32 size;
                struct resource *resource;
                unsigned int index;
 
                size = mc_fixed_resources[i].size;
                index = mc_fixed_resources[i].index;
                if (!mc_fixed_resources[i].get_resource(dev, index, &base, &size))
                        continue;
 
                resource = new_resource(dev, mc_fixed_resources[i].index);
                resource->flags = IORESOURCE_MEM | IORESOURCE_FIXED | IORESOURCE_STORED |
                                  IORESOURCE_RESERVE | IORESOURCE_ASSIGNED;
 
                resource->base = base;
                resource->size = size;
                printk(BIOS_DEBUG, "%s: Adding %s @ %x 0x%08lx-0x%08lx.\n",
                       __func__, mc_fixed_resources[i].description, index,
                       (unsigned long)base, (unsigned long)(base + size - 1));
        }
 
        mmconf_resource(dev, PCIEXBAR);
}
 
/*
 * Host Memory Map:
 *
 * +--------------------------+ TOUUD
 * |                          |
 * +--------------------------+ 4GiB
 * |     PCI Address Space    |
 * +--------------------------+ TOLUD (also maps into MC address space)
 * |     iGD                  |
 * +--------------------------+ BDSM
 * |     GTT                  |
 * +--------------------------+ BGSM
 * |     TSEG                 |
 * +--------------------------+ TSEGMB
 * |     DPR                  |
 * +--------------------------+ (DPR top - DPR size)
 * |     Usage DRAM           |
 * +--------------------------+ 0
 *
 * Some of the base registers above can be equal, making the size of the regions within 0.
 * This is because the memory controller internally subtracts the base registers from each
 * other to determine sizes of the regions. In other words, the memory map regions are always
 * in a fixed order, no matter what sizes they have.
 */
 
struct map_entry {
        int reg;
        int is_64_bit;
        int is_limit;
        const char *description;
};
 
static void read_map_entry(struct device *dev, struct map_entry *entry, uint64_t *result)
{
        uint64_t value;
        uint64_t mask;
 
        /* All registers have a 1MiB granularity */
        mask = ((1ULL << 20) - 1);
        mask = ~mask;
 
        value = 0;
 
        if (entry->is_64_bit) {
                value = pci_read_config32(dev, entry->reg + 4);
                value <<= 32;
        }
 
        value |= pci_read_config32(dev, entry->reg);
        value &= mask;
 
        if (entry->is_limit)
                value |= ~mask;
 
        *result = value;
}
 
#define MAP_ENTRY(reg_, is_64_, is_limit_, desc_) \
        { \
                .reg = reg_,           \
                .is_64_bit = is_64_,   \
                .is_limit = is_limit_, \
                .description = desc_,  \
        }
 
#define MAP_ENTRY_BASE_32(reg_, desc_)  MAP_ENTRY(reg_, 0, 0, desc_)
#define MAP_ENTRY_BASE_64(reg_, desc_)  MAP_ENTRY(reg_, 1, 0, desc_)
#define MAP_ENTRY_LIMIT_64(reg_, desc_) MAP_ENTRY(reg_, 1, 1, desc_)
 
enum {
        TOM_REG,
        TOUUD_REG,
        MESEG_BASE_REG,
        MESEG_LIMIT_REG,
        REMAP_BASE_REG,
        REMAP_LIMIT_REG,
        TOLUD_REG,
        BGSM_REG,
        BDSM_REG,
        TSEG_REG,
        /* Must be last */
        NUM_MAP_ENTRIES,
};
 
static struct map_entry memory_map[NUM_MAP_ENTRIES] = {
        [TOM_REG]         = MAP_ENTRY_BASE_64(TOM, "TOM"),
        [TOUUD_REG]       = MAP_ENTRY_BASE_64(TOUUD, "TOUUD"),
        [MESEG_BASE_REG]  = MAP_ENTRY_BASE_64(MESEG_BASE, "MESEG_BASE"),
        [MESEG_LIMIT_REG] = MAP_ENTRY_LIMIT_64(MESEG_LIMIT, "MESEG_LIMIT"),
        [REMAP_BASE_REG]  = MAP_ENTRY_BASE_64(REMAPBASE, "REMAP_BASE"),
        [REMAP_LIMIT_REG] = MAP_ENTRY_LIMIT_64(REMAPLIMIT, "REMAP_LIMIT"),
        [TOLUD_REG]       = MAP_ENTRY_BASE_32(TOLUD, "TOLUD"),
        [BDSM_REG]        = MAP_ENTRY_BASE_32(BDSM, "BDSM"),
        [BGSM_REG]        = MAP_ENTRY_BASE_32(BGSM, "BGSM"),
        [TSEG_REG]        = MAP_ENTRY_BASE_32(TSEG, "TSEGMB"),
};
 
static void mc_read_map_entries(struct device *dev, uint64_t *values)
{
        int i;
        for (i = 0; i < NUM_MAP_ENTRIES; i++) {
                read_map_entry(dev, &memory_map[i], &values[i]);
        }
}
 
static void mc_report_map_entries(struct device *dev, uint64_t *values)
{
        int i;
        for (i = 0; i < NUM_MAP_ENTRIES; i++) {
                printk(BIOS_DEBUG, "MC MAP: %s: 0x%llx\n",
                       memory_map[i].description, values[i]);
        }
        /* One can validate the BDSM and BGSM against the GGC */
        printk(BIOS_DEBUG, "MC MAP: GGC: 0x%x\n", pci_read_config16(dev, GGC));
}
 
static void mc_add_dram_resources(struct device *dev, int *resource_cnt)
{
        unsigned long base_k, size_k, touud_k, index;
        struct resource *resource;
        uint64_t mc_values[NUM_MAP_ENTRIES];
 
        /* Read in the MAP registers and report their values */
        mc_read_map_entries(dev, &mc_values[0]);
        mc_report_map_entries(dev, &mc_values[0]);
 
        /*
         * DMA Protected Range can be reserved below TSEG for PCODE patch
         * or TXT/Boot Guard related data.  Rather than report a base address,
         * the DPR register reports the TOP of the region, which is the same
         * as TSEG base. The region size is reported in MiB in bits 11:4.
         */
        const union dpr_register dpr = {
                .raw = pci_read_config32(dev, DPR),
        };
        printk(BIOS_DEBUG, "MC MAP: DPR: 0x%x\n", dpr.raw);
 
        /*
         * These are the host memory ranges that should be added:
         * - 0 -> 0xa0000:    cacheable
         * - 0xc0000 -> TSEG: cacheable
         * - TSEG -> BGSM:    cacheable with standard MTRRs and reserved
         * - BGSM -> TOLUD:   not cacheable with standard MTRRs and reserved
         * - 4GiB -> TOUUD:   cacheable
         *
         * The default SMRAM space is reserved so that the range doesn't have to be saved
         * during S3 Resume. Once marked reserved the OS cannot use the memory. This is a
         * bit of an odd place to reserve the region, but the CPU devices don't have
         * dev_ops->read_resources() called on them.
         *
         * The range 0xa0000 -> 0xc0000 does not have any resources associated with it to
         * handle legacy VGA memory. If this range is not omitted the mtrr code will setup
         * the area as cacheable, causing VGA access to not work.
         *
         * The TSEG region is mapped as cacheable so that one can perform SMRAM relocation
         * faster. Once the SMRR is enabled, the SMRR takes precedence over the existing
         * MTRRs covering this region.
         *
         * It should be noted that cacheable entry types need to be added in order. The reason
         * is that the current MTRR code assumes this and falls over itself if it isn't.
         *
         * The resource index starts low and should not meet or exceed PCI_BASE_ADDRESS_0.
         */
        index = *resource_cnt;
 
        /* 0 - > 0xa0000 */
        base_k = 0;
        size_k = (0xa0000 >> 10) - base_k;
        ram_resource(dev, index++, base_k, size_k);
 
        /* 0xc0000 -> TSEG - DPR */
        base_k = 0xc0000 >> 10;
        size_k = (unsigned long)(mc_values[TSEG_REG] >> 10) - base_k;
        size_k -= dpr.size * MiB / KiB;
        ram_resource(dev, index++, base_k, size_k);
 
        /* TSEG - DPR -> BGSM */
        resource = new_resource(dev, index++);
        resource->base = mc_values[TSEG_REG] - dpr.size * MiB;
        resource->size = mc_values[BGSM_REG] - resource->base;
        resource->flags = IORESOURCE_MEM | IORESOURCE_FIXED | IORESOURCE_STORED |
                          IORESOURCE_RESERVE | IORESOURCE_ASSIGNED | IORESOURCE_CACHEABLE;
 
        /* BGSM -> TOLUD. If the IGD is disabled, BGSM can equal TOLUD. */
        if (mc_values[BGSM_REG] != mc_values[TOLUD_REG]) {
                resource = new_resource(dev, index++);
                resource->base = mc_values[BGSM_REG];
                resource->size = mc_values[TOLUD_REG] - resource->base;
                resource->flags = IORESOURCE_MEM | IORESOURCE_FIXED | IORESOURCE_STORED |
                                  IORESOURCE_RESERVE | IORESOURCE_ASSIGNED;
        }
 
        /* 4GiB -> TOUUD */
        base_k = 4096 * 1024; /* 4GiB */
        touud_k = mc_values[TOUUD_REG] >> 10;
        size_k = touud_k - base_k;
        if (touud_k > base_k)
                ram_resource(dev, index++, base_k, size_k);
 
        /* Reserve everything between A segment and 1MB:
         *
         * 0xa0000 - 0xbffff: Legacy VGA
         * 0xc0000 - 0xfffff: RAM
         */
        mmio_resource(dev, index++, (0xa0000 >> 10), (0xc0000 - 0xa0000) >> 10);
        reserved_ram_resource(dev, index++, (0xc0000 >> 10), (0x100000 - 0xc0000) >> 10);
 
        *resource_cnt = index;
}
 
static void mc_read_resources(struct device *dev)
{
        int index = 0;
        const bool vtd_capable = !(pci_read_config32(dev, CAPID0_A) & VTD_DISABLE);
 
        /* Read standard PCI resources */
        pci_dev_read_resources(dev);
 
        /* Add all fixed MMIO resources */
        mc_add_fixed_mmio_resources(dev);
 
        /* Add VT-d MMIO resources, if capable */
        if (vtd_capable) {
                mmio_resource(dev, index++, GFXVT_BASE_ADDRESS / KiB, GFXVT_BASE_SIZE / KiB);
                mmio_resource(dev, index++, VTVC0_BASE_ADDRESS / KiB, VTVC0_BASE_SIZE / KiB);
        }
 
        /* Calculate and add DRAM resources */
        mc_add_dram_resources(dev, &index);
}
 
/*
 * The Mini-HD audio device is disabled whenever the IGD is. This is because it provides
 * audio over the integrated graphics port(s), which requires the IGD to be functional.
 */
static void disable_devices(void)
{
        static const struct {
                const unsigned int devfn;
                const u32 mask;
                const char *const name;
        } nb_devs[] = {
                { PCI_DEVFN(1, 2), DEVEN_D1F2EN, "PEG12" },
                { PCI_DEVFN(1, 1), DEVEN_D1F1EN, "PEG11" },
                { PCI_DEVFN(1, 0), DEVEN_D1F0EN, "PEG10" },
                { PCI_DEVFN(2, 0), DEVEN_D2EN | DEVEN_D3EN, "IGD" },
                { PCI_DEVFN(3, 0), DEVEN_D3EN, "Mini-HD audio" },
                { PCI_DEVFN(4, 0), DEVEN_D4EN, "\"device 4\"" },
                { PCI_DEVFN(7, 0), DEVEN_D7EN, "\"device 7\"" },
        };
 
        struct device *host_dev = pcidev_on_root(0, 0);
        u32 deven;
        size_t i;
 
        if (!host_dev)
                return;
 
        deven = pci_read_config32(host_dev, DEVEN);
 
        for (i = 0; i < ARRAY_SIZE(nb_devs); i++) {
                struct device *dev = pcidev_path_on_root(nb_devs[i].devfn);
                if (!dev || !dev->enabled) {
                        printk(BIOS_DEBUG, "Disabling %s.\n", nb_devs[i].name);
                        deven &= ~nb_devs[i].mask;
                }
        }
 
        pci_write_config32(host_dev, DEVEN, deven);
}
 
static void init_egress(void)
{
        /* VC0: Enable, ID0, TC0 */
        epbar_write32(EPVC0RCTL, 1 << 31 | 0 << 24 | 1 << 0);
 
        /* No Low Priority Extended VCs, one Extended VC */
        epbar_write32(EPPVCCAP1, 0 << 4 | 1 << 0);
 
        /* VC1: Enable, ID1, TC1 */
        epbar_write32(EPVC1RCTL, 1 << 31 | 1 << 24 | 1 << 1);
 
        /* Poll the VC1 Negotiation Pending bit */
        while ((epbar_read16(EPVC1RSTS) & (1 << 1)) != 0)
                ;
}
 
static void northbridge_dmi_init(void)
{
        const bool is_haswell_h = !CONFIG(INTEL_LYNXPOINT_LP);
 
        /* Steps prior to DMI ASPM */
        if (is_haswell_h) {
                /* Configure DMI De-Emphasis */
                dmibar_setbits16(DMILCTL2, 1 << 6);     /* 0b: -6.0 dB, 1b: -3.5 dB */
 
                dmibar_setbits32(DMIL0SLAT, 1 << 31);
                dmibar_setbits32(DMILLTC, 1 << 29);
 
                dmibar_clrsetbits32(DMI_AFE_PM_TMR, 0x1f, 0x13);
        }
 
        /* Clear error status bits */
        dmibar_write32(DMIUESTS, 0xffffffff);
        dmibar_write32(DMICESTS, 0xffffffff);
 
        if (is_haswell_h) {
                /* Enable ASPM L0s and L1 on SA link, should happen before PCH link */
                dmibar_setbits16(DMILCTL, 1 << 1 | 1 << 0);
        }
}
 
static void northbridge_topology_init(void)
{
        const u32 eple_a[3] = { EPLE2A, EPLE3A, EPLE4A };
        const u32 eple_d[3] = { EPLE2D, EPLE3D, EPLE4D };
 
        /* Set the CID1 Egress Port 0 Root Topology */
        epbar_clrsetbits32(EPESD, 0xff << 16, 1 << 16);
 
        epbar_clrsetbits32(EPLE1D, 0xff << 16, 1 | 1 << 16);
        epbar_write32(EPLE1A, CONFIG_FIXED_DMIBAR_MMIO_BASE);
        epbar_write32(EPLE1A + 4, 0);
 
        for (unsigned int i = 0; i <= 2; i++) {
                const struct device *const dev = pcidev_on_root(1, i);
 
                if (!dev || !dev->enabled)
                        continue;
 
                epbar_write32(eple_a[i], (u32)PCI_DEV(0, 1, i));
                epbar_write32(eple_a[i] + 4, 0);
 
                epbar_clrsetbits32(eple_d[i], 0xff << 16, 1 | 1 << 16);
 
                pci_update_config32(dev, PEG_ESD, ~(0xff << 16), (1 << 16));
                pci_write_config32(dev, PEG_LE1A, CONFIG_FIXED_EPBAR_MMIO_BASE);
                pci_write_config32(dev, PEG_LE1A + 4, 0);
                pci_update_config32(dev, PEG_LE1D, ~(0xff << 16), (1 << 16) | 1);
 
                /* Read and write to lock register */
                pci_or_config32(dev, PEG_DCAP2, 0);
        }
 
        /* Set the CID1 DMI Port Root Topology */
        dmibar_clrsetbits32(DMIESD, 0xff << 16, 1 << 16);
 
        dmibar_clrsetbits32(DMILE1D, 0xffff << 16, 1 | 2 << 16);
        dmibar_write32(DMILE1A, CONFIG_FIXED_RCBA_MMIO_BASE);
        dmibar_write32(DMILE1A + 4, 0);
 
        dmibar_write32(DMILE2A, CONFIG_FIXED_EPBAR_MMIO_BASE);
        dmibar_write32(DMILE2A + 4, 0);
        dmibar_clrsetbits32(DMILE2D, 0xff << 16, 1 | 1 << 16);
 
        /* Program RO and Write-Once Registers */
        dmibar_setbits32(DMIPVCCAP1, 0);
        dmibar_setbits32(DMILCAP, 0);
}
 
static void northbridge_init(struct device *dev)
{
        init_egress();
        northbridge_dmi_init();
        northbridge_topology_init();
 
        /* Enable Power Aware Interrupt Routing. */
        mchbar_clrsetbits8(INTRDIRCTL, 0x7, 0x4);       /* Clear 2:0, set Fixed Priority */
 
        disable_devices();
 
        /*
         * Set bits 0 + 1 of BIOS_RESET_CPL to indicate to the CPU
         * that BIOS has initialized memory and power management.
         */
        mchbar_setbits8(BIOS_RESET_CPL, 3);
        printk(BIOS_DEBUG, "Set BIOS_RESET_CPL\n");
 
        /* Configure turbo power limits 1ms after reset complete bit. */
        mdelay(1);
        set_power_limits(28);
}
 
static void northbridge_final(struct device *dev)
{
        pci_or_config16(dev, GGC,         1 << 0);
        pci_or_config32(dev, DPR,         1 << 0);
        pci_or_config32(dev, MESEG_LIMIT, 1 << 10);
        pci_or_config32(dev, REMAPBASE,   1 << 0);
        pci_or_config32(dev, REMAPLIMIT,  1 << 0);
        pci_or_config32(dev, TOM,         1 << 0);
        pci_or_config32(dev, TOUUD,       1 << 0);
        pci_or_config32(dev, BDSM,        1 << 0);
        pci_or_config32(dev, BGSM,        1 << 0);
        pci_or_config32(dev, TSEG,        1 << 0);
        pci_or_config32(dev, TOLUD,       1 << 0);
 
        /* Memory Controller Lockdown */
        mchbar_setbits32(MC_LOCK, 0x8f);
 
        mchbar_setbits32(MMIO_PAVP_MSG, 1 << 0);        /* PAVP */
        mchbar_setbits32(PCU_DDR_PTM_CTL, 1 << 5);      /* DDR PTM */
        mchbar_setbits32(DMIVCLIM, 1 << 31);
        mchbar_setbits32(CRDTLCK, 1 << 0);
        mchbar_setbits32(MCARBLCK, 1 << 0);
        mchbar_setbits32(REQLIM, 1 << 31);
        mchbar_setbits32(UMAGFXCTL, 1 << 0);            /* UMA GFX */
        mchbar_setbits32(VTDTRKLCK, 1 << 0);            /* VTDTRK */
 
        /* Read+write the following */
        mchbar_setbits32(VDMBDFBARKVM, 0);
        mchbar_setbits32(VDMBDFBARPAVP, 0);
        mchbar_setbits32(HDAUDRID, 0);
}
 
static struct device_operations mc_ops = {
        .read_resources         = mc_read_resources,
        .set_resources          = pci_dev_set_resources,
        .enable_resources       = pci_dev_enable_resources,
        .init                   = northbridge_init,
        .final                  = northbridge_final,
        .acpi_fill_ssdt         = generate_cpu_entries,
        .ops_pci                = &pci_dev_ops_pci,
};
 
static const unsigned short mc_pci_device_ids[] = {
        0x0c00, /* Desktop */
        0x0c04, /* Mobile */
        0x0a04, /* ULT */
        0x0c08, /* Server */
        0x0d00, /* Crystal Well Desktop */
        0x0d04, /* Crystal Well Mobile */
        0x0d08, /* Crystal Well Server (by extrapolation) */
        0
};
 
static const struct pci_driver mc_driver_hsw __pci_driver = {
        .ops     = &mc_ops,
        .vendor  = PCI_VID_INTEL,
        .devices = mc_pci_device_ids,
};
 
static struct device_operations cpu_bus_ops = {
        .read_resources   = noop_read_resources,
        .set_resources    = noop_set_resources,
        .init             = mp_cpu_bus_init,
};
 
static void enable_dev(struct device *dev)
{
        /* Set the operations if it is a special bus type. */
        if (dev->path.type == DEVICE_PATH_DOMAIN) {
                dev->ops = &pci_domain_ops;
        } else if (dev->path.type == DEVICE_PATH_CPU_CLUSTER) {
                dev->ops = &cpu_bus_ops;
        }
}
 
struct chip_operations northbridge_intel_haswell_ops = {
        CHIP_NAME("Intel Haswell integrated Northbridge")
        .enable_dev = enable_dev,
};