/*
* Intel X38 Memory Controller kernel module
* Copyright (C) 2008 Cluster Computing, Inc.
*
* This file may be distributed under the terms of the
* GNU General Public License.
*
* This file is based on i3200_edac.c
*
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/pci_ids.h>
#include <linux/slab.h>
#include <linux/edac.h>
#include "edac_core.h"
#define X38_REVISION "1.1"
#define EDAC_MOD_STR "x38_edac"
#define PCI_DEVICE_ID_INTEL_X38_HB 0x29e0
#define X38_RANKS 8
#define X38_RANKS_PER_CHANNEL 4
#define X38_CHANNELS 2
/* Intel X38 register addresses - device 0 function 0 - DRAM Controller */
#define X38_MCHBAR_LOW 0x48 /* MCH Memory Mapped Register BAR */
#define X38_MCHBAR_HIGH 0x4c
#define X38_MCHBAR_MASK 0xfffffc000ULL /* bits 35:14 */
#define X38_MMR_WINDOW_SIZE 16384
#define X38_TOM 0xa0 /* Top of Memory (16b)
*
* 15:10 reserved
* 9:0 total populated physical memory
*/
#define X38_TOM_MASK 0x3ff /* bits 9:0 */
#define X38_TOM_SHIFT 26 /* 64MiB grain */
#define X38_ERRSTS 0xc8 /* Error Status Register (16b)
*
* 15 reserved
* 14 Isochronous TBWRR Run Behind FIFO Full
* (ITCV)
* 13 Isochronous TBWRR Run Behind FIFO Put
* (ITSTV)
* 12 reserved
* 11 MCH Thermal Sensor Event
* for SMI/SCI/SERR (GTSE)
* 10 reserved
* 9 LOCK to non-DRAM Memory Flag (LCKF)
* 8 reserved
* 7 DRAM Throttle Flag (DTF)
* 6:2 reserved
* 1 Multi-bit DRAM ECC Error Flag (DMERR)
* 0 Single-bit DRAM ECC Error Flag (DSERR)
*/
#define X38_ERRSTS_UE 0x0002
#define X38_ERRSTS_CE 0x0001
#define X38_ERRSTS_BITS (X38_ERRSTS_UE | X38_ERRSTS_CE)
/* Intel MMIO register space - device 0 function 0 - MMR space */
#define X38_C0DRB 0x200 /* Channel 0 DRAM Rank Boundary (16b x 4)
*
* 15:10 reserved
* 9:0 Channel 0 DRAM Rank Boundary Address
*/
#define X38_C1DRB 0x600 /* Channel 1 DRAM Rank Boundary (16b x 4) */
#define X38_DRB_MASK 0x3ff /* bits 9:0 */
#define X38_DRB_SHIFT 26 /* 64MiB grain */
#define X38_C0ECCERRLOG 0x280 /* Channel 0 ECC Error Log (64b)
*
* 63:48 Error Column Address (ERRCOL)
* 47:32 Error Row Address (ERRROW)
* 31:29 Error Bank Address (ERRBANK)
* 28:27 Error Rank Address (ERRRANK)
* 26:24 reserved
* 23:16 Error Syndrome (ERRSYND)
* 15: 2 reserved
* 1 Multiple Bit Error Status (MERRSTS)
* 0 Correctable Error Status (CERRSTS)
*/
#define X38_C1ECCERRLOG 0x680 /* Channel 1 ECC Error Log (64b) */
#define X38_ECCERRLOG_CE 0x1
#define X38_ECCERRLOG_UE 0x2
#define X38_ECCERRLOG_RANK_BITS 0x18000000
#define X38_ECCERRLOG_SYNDROME_BITS 0xff0000
#define X38_CAPID0 0xe0 /* see P.94 of spec for details */
static int x38_channel_num;
static int how_many_channel(struct pci_dev *pdev)
{
unsigned char capid0_8b; /* 8th byte of CAPID0 */
pci_read_config_byte(pdev, X38_CAPID0 + 8, &capid0_8b);
if (capid0_8b & 0x20) { /* check DCD: Dual Channel Disable */
debugf0("In single channel mode.\n");
x38_channel_num = 1;
} else {
debugf0("In dual channel mode.\n");
x38_channel_num = 2;
}
return x38_channel_num;
}
static unsigned long eccerrlog_syndrome(u64 log)
{
return (log & X38_ECCERRLOG_SYNDROME_BITS) >> 16;
}
static int eccerrlog_row(int channel, u64 log)
{
return ((log & X38_ECCERRLOG_RANK_BITS) >> 27) |
(channel * X38_RANKS_PER_CHANNEL);
}
enum x38_chips {
X38 = 0,
};
struct x38_dev_info {
const char *ctl_name;
};
struct x38_error_info {
u16 errsts;
u16 errsts2;
u64 eccerrlog[X38_CHANNELS];
};
static const struct x38_dev_info x38_devs[] = {
[X38] = {
.ctl_name = "x38"},
};
static struct pci_dev *mci_pdev;
static int x38_registered = 1;
static void x38_clear_error_info(struct mem_ctl_info *mci)
{
struct pci_dev *pdev;
pdev = to_pci_dev(mci->dev);
/*
* Clear any error bits.
* (Yes, we really clear bits by writing 1 to them.)
*/
pci_write_bits16(pdev, X38_ERRSTS, X38_ERRSTS_BITS,
X38_ERRSTS_BITS);
}
static u64 x38_readq(const void __iomem *addr)
{
return readl(addr) | (((u64)readl(addr + 4)) << 32);
}
static void x38_get_and_clear_error_info(struct mem_ctl_info *mci,
struct x38_error_info *info)
{
struct pci_dev *pdev;
void __iomem *window = mci->pvt_info;
pdev = to_pci_dev(mci->dev);
/*
* This is a mess because there is no atomic way to read all the
* registers at once and the registers can transition from CE being
* overwritten by UE.
*/
pci_read_config_word(pdev, X38_ERRSTS, &info->errsts);
if (!(info->errsts & X38_ERRSTS_BITS))
return;
info->eccerrlog[0] = x38_readq(window + X38_C0ECCERRLOG);
if (x38_channel_num == 2)
info->eccerrlog[1] = x38_readq(window + X38_C1ECCERRLOG);
pci_read_config_word(pdev, X38_ERRSTS, &info->errsts2);
/*
* If the error is the same for both reads then the first set
* of reads is valid. If there is a change then there is a CE
* with no info and the second set of reads is valid and
* should be UE info.
*/
if ((info->errsts ^ info->errsts2) & X38_ERRSTS_BITS) {
info->eccerrlog[0] = x38_readq(window + X38_C0ECCERRLOG);
if (x38_channel_num == 2)
info->eccerrlog[1] =
x38_readq(window + X38_C1ECCERRLOG);
}
x38_clear_error_info(mci);
}
static void x38_process_error_info(struct mem_ctl_info *mci,
struct x38_error_info *info)
{
int channel;
u64 log;
if (!(info->errsts & X38_ERRSTS_BITS))
return;
if ((info->errsts ^ info->errsts2) & X38_ERRSTS_BITS) {
edac_mc_handle_ce_no_info(mci, "UE overwrote CE");
info->errsts = info->errsts2;
}
for (channel = 0; channel < x38_channel_num; channel++) {
log = info->eccerrlog[channel];
if (log & X38_ECCERRLOG_UE) {
edac_mc_handle_ue(mci, 0, 0,
eccerrlog_row(channel, log), "x38 UE");
} else if (log & X38_ECCERRLOG_CE) {
edac_mc_handle_ce(mci, 0, 0,
eccerrlog_syndrome(log),
eccerrlog_row(channel, log), 0, "x38 CE");
}
}
}
static void x38_check(struct mem_ctl_info *mci)
{
struct x38_error_info info;
debugf1("MC%d: %s()\n", mci->mc_idx, __func__);
x38_get_and_clear_error_info(mci, &info);
x38_process_error_info(mci, &info);
}
void __iomem *x38_map_mchbar(struct pci_dev *pdev)
{
union {
u64 mchbar;
struct {
u32 mchbar_low;
u32 mchbar_high;
};
} u;
void __iomem *window;
pci_read_config_dword(pdev, X38_MCHBAR_LOW, &u.mchbar_low);
pci_write_config_dword(pdev, X38_MCHBAR_LOW, u.mchbar_low | 0x1);
pci_read_config_dword(pdev, X38_MCHBAR_HIGH, &u.mchbar_high);
u.mchbar &= X38_MCHBAR_MASK;
if (u.mchbar != (resource_size_t)u.mchbar) {
printk(KERN_ERR
"x38: mmio space beyond accessible range (0x%llx)\n",
(unsigned long long)u.mchbar);
return NULL;
}
window = ioremap_nocache(u.mchbar, X38_MMR_WINDOW_SIZE);
if (!window)
printk(KERN_ERR "x38: cannot map mmio space at 0x%llx\n",
(unsigned long long)u.mchbar);
return window;
}
static void x38_get_drbs(void __iomem *window,
u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL])
{
int i;
for (i = 0; i < X38_RANKS_PER_CHANNEL; i++) {
drbs[0][i] = readw(window + X38_C0DRB + 2*i) & X38_DRB_MASK;
drbs[1][i] = readw(window + X38_C1DRB + 2*i) & X38_DRB_MASK;
}
}
static bool x38_is_stacked(struct pci_dev *pdev,
u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL])
{
u16 tom;
pci_read_config_word(pdev, X38_TOM, &tom);
tom &= X38_TOM_MASK;
return drbs[X38_CHANNELS - 1][X38_RANKS_PER_CHANNEL - 1] == tom;
}
static unsigned long drb_to_nr_pages(
u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL],
bool stacked, int channel, int rank)
{
int n;
n = drbs[channel][rank];
if (rank > 0)
n -= drbs[channel][rank - 1];
if (stacked && (channel == 1) && drbs[channel][rank] ==
drbs[channel][X38_RANKS_PER_CHANNEL - 1]) {
n -= drbs[0][X38_RANKS_PER_CHANNEL - 1];
}
n <<= (X38_DRB_SHIFT - PAGE_SHIFT);
return n;
}
static int x38_probe1(struct pci_dev *pdev, int dev_idx)
{
int rc;
int i;
struct mem_ctl_info *mci = NULL;
unsigned long last_page;
u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL];
bool stacked;
void __iomem *window;
debugf0("MC: %s()\n", __func__);
window = x38_map_mchbar(pdev);
if (!window)
return -ENODEV;
x38_get_drbs(window, drbs);
how_many_channel(pdev);
/* FIXME: unconventional pvt_info usage */
mci = edac_mc_alloc(0, X38_RANKS, x38_channel_num, 0);
if (!mci)
return -ENOMEM;
debugf3("MC: %s(): init mci\n", __func__);
mci->dev = &pdev->dev;
mci->mtype_cap = MEM_FLAG_DDR2;
mci->edac_ctl_cap = EDAC_FLAG_SECDED;
mci->edac_cap = EDAC_FLAG_SECDED;
mci->mod_name = EDAC_MOD_STR;
mci->mod_ver = X38_REVISION;
mci->ctl_name = x38_devs[dev_idx].ctl_name;
mci->dev_name = pci_name(pdev);
mci->edac_check = x38_check;
mci->ctl_page_to_phys = NULL;
mci->pvt_info = window;
stacked = x38_is_stacked(pdev, drbs);
/*
* The dram rank boundary (DRB) reg values are boundary addresses
* for each DRAM rank with a granularity of 64MB. DRB regs are
* cumulative; the last one will contain the total memory
* contained in all ranks.
*/
last_page = -1UL;
for (i = 0; i < mci->nr_csrows; i++) {
unsigned long nr_pages;
struct csrow_info *csrow = &mci->csrows[i];
nr_pages = drb_to_nr_pages(drbs, stacked,
i / X38_RANKS_PER_CHANNEL,
i % X38_RANKS_PER_CHANNEL);
if (nr_pages == 0) {
csrow->mtype = MEM_EMPTY;
continue;
}
csrow->first_page = last_page + 1;
last_page += nr_pages;
csrow->last_page = last_page;
csrow->nr_pages = nr_pages;
csrow->grain = nr_pages << PAGE_SHIFT;
csrow->mtype = MEM_DDR2;
csrow->dtype = DEV_UNKNOWN;
csrow->edac_mode = EDAC_UNKNOWN;
}
x38_clear_error_info(mci);
rc = -ENODEV;
if (edac_mc_add_mc(mci)) {
debugf3("MC: %s(): failed edac_mc_add_mc()\n", __func__);
goto fail;
}
/* get this far and it's successful */
debugf3("MC: %s(): success\n", __func__);
return 0;
fail:
iounmap(window);
if (mci)
edac_mc_free(mci);
return rc;
}
static int __devinit x38_init_one(struct pci_dev *pdev,
const struct pci_device_id *ent)
{
int rc;
debugf0("MC: %s()\n", __func__);
if (pci_enable_device(pdev) < 0)
return -EIO;
rc = x38_probe1(pdev, ent->driver_data);
if (!mci_pdev)
mci_pdev = pci_dev_get(pdev);
return rc;
}
static void __devexit x38_remove_one(struct pci_dev *pdev)
{
struct mem_ctl_info *mci;
debugf0("%s()\n", __func__);
mci = edac_mc_del_mc(&pdev->dev);
if (!mci)
return;
iounmap(mci->pvt_info);
edac_mc_free(mci);
}
static const struct pci_device_id x38_pci_tbl[] __devinitdata = {
{
PCI_VEND_DEV(INTEL, X38_HB), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
X38},
{
0,
} /* 0 terminated list. */
};
MODULE_DEVICE_TABLE(pci, x38_pci_tbl);
static struct pci_driver x38_driver = {
.name = EDAC_MOD_STR,
.probe = x38_init_one,
.remove = __devexit_p(x38_remove_one),
.id_table = x38_pci_tbl,
};
static int __init x38_init(void)
{
int pci_rc;
debugf3("MC: %s()\n", __func__);
/* Ensure that the OPSTATE is set correctly for POLL or NMI */
opstate_init();
pci_rc = pci_register_driver(&x38_driver);
if (pci_rc < 0)
goto fail0;
if (!mci_pdev) {
x38_registered = 0;
mci_pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
PCI_DEVICE_ID_INTEL_X38_HB, NULL);
if (!mci_pdev) {
debugf0("x38 pci_get_device fail\n");
pci_rc = -ENODEV;
goto fail1;
}
pci_rc = x38_init_one(mci_pdev, x38_pci_tbl);
if (pci_rc < 0) {
debugf0("x38 init fail\n");
pci_rc = -ENODEV;
goto fail1;
}
}
return 0;
fail1:
pci_unregister_driver(&x38_driver);
fail0:
if (mci_pdev)
pci_dev_put(mci_pdev);
return pci_rc;
}
static void __exit x38_exit(void)
{
debugf3("MC: %s()\n", __func__);
pci_unregister_driver(&x38_driver);
if (!x38_registered) {
x38_remove_one(mci_pdev);
pci_dev_put(mci_pdev);
}
}
module_init(x38_init);
module_exit(x38_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Cluster Computing, Inc. Hitoshi Mitake");
MODULE_DESCRIPTION("MC support for Intel X38 memory hub controllers");
module_param(edac_op_state, int, 0444);
MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");
