edac: i3200 memory controller driver

A driver for the Intel 3200 and 3210 memory controllers.  It has only had
light testing so far, and currently makes no attempt to decode error
addresses at anything finer than csrow granularity.

Signed-off-by: Jason Uhlenkott <juhlenko@akamai.com>
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 527 insertions, 0 deletions

diff --git a/drivers/edac/i3200_edac.c b/drivers/edac/i3200_edac.c
new file mode 100644
index 000000000000..fde4db91c4d2
--- /dev/null
+++ b/drivers/edac/i3200_edac.c
@@ -0,0 +1,527 @@
+/*
+ * Intel 3200/3210 Memory Controller kernel module
+ * Copyright (C) 2008-2009 Akamai Technologies, Inc.
+ * Portions by Hitoshi Mitake <h.mitake@gmail.com>.
+ *
+ * This file may be distributed under the terms of the
+ * GNU General Public License.
+ */
+
+#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 <linux/io.h>
+#include "edac_core.h"
+
+#define I3200_REVISION        "1.1"
+
+#define EDAC_MOD_STR        "i3200_edac"
+
+#define PCI_DEVICE_ID_INTEL_3200_HB    0x29f0
+
+#define I3200_RANKS             8
+#define I3200_RANKS_PER_CHANNEL 4
+#define I3200_CHANNELS          2
+
+/* Intel 3200 register addresses - device 0 function 0 - DRAM Controller */
+
+#define I3200_MCHBAR_LOW        0x48    /* MCH Memory Mapped Register BAR */
+#define I3200_MCHBAR_HIGH       0x4c
+#define I3200_MCHBAR_MASK       0xfffffc000ULL  /* bits 35:14 */
+#define I3200_MMR_WINDOW_SIZE   16384
+
+#define I3200_TOM               0xa0    /* Top of Memory (16b)
+                 *
+                 * 15:10 reserved
+                 *  9:0  total populated physical memory
+                 */
+#define I3200_TOM_MASK          0x3ff   /* bits 9:0 */
+#define I3200_TOM_SHIFT         26      /* 64MiB grain */
+
+#define I3200_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 I3200_ERRSTS_UE         0x0002
+#define I3200_ERRSTS_CE         0x0001
+#define I3200_ERRSTS_BITS       (I3200_ERRSTS_UE | I3200_ERRSTS_CE)
+
+
+/* Intel  MMIO register space - device 0 function 0 - MMR space */
+
+#define I3200_C0DRB     0x200   /* Channel 0 DRAM Rank Boundary (16b x 4)
+                 *
+                 * 15:10 reserved
+                 *  9:0  Channel 0 DRAM Rank Boundary Address
+                 */
+#define I3200_C1DRB     0x600   /* Channel 1 DRAM Rank Boundary (16b x 4) */
+#define I3200_DRB_MASK  0x3ff   /* bits 9:0 */
+#define I3200_DRB_SHIFT 26      /* 64MiB grain */
+
+#define I3200_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 I3200_C1ECCERRLOG               0x680   /* Chan 1 ECC Error Log (64b) */
+#define I3200_ECCERRLOG_CE              0x1
+#define I3200_ECCERRLOG_UE              0x2
+#define I3200_ECCERRLOG_RANK_BITS       0x18000000
+#define I3200_ECCERRLOG_RANK_SHIFT      27
+#define I3200_ECCERRLOG_SYNDROME_BITS   0xff0000
+#define I3200_ECCERRLOG_SYNDROME_SHIFT  16
+#define I3200_CAPID0                    0xe0    /* P.95 of spec for details */
+
+struct i3200_priv {
+        void __iomem *window;
+};
+
+static int nr_channels;
+
+static int how_many_channels(struct pci_dev *pdev)
+{
+        unsigned char capid0_8b; /* 8th byte of CAPID0 */
+
+        pci_read_config_byte(pdev, I3200_CAPID0 + 8, &capid0_8b);
+        if (capid0_8b & 0x20) { /* check DCD: Dual Channel Disable */
+                debugf0("In single channel mode.\n");
+                return 1;
+        } else {
+                debugf0("In dual channel mode.\n");
+                return 2;
+        }
+}
+
+static unsigned long eccerrlog_syndrome(u64 log)
+{
+        return (log & I3200_ECCERRLOG_SYNDROME_BITS) >>
+                I3200_ECCERRLOG_SYNDROME_SHIFT;
+}
+
+static int eccerrlog_row(int channel, u64 log)
+{
+        u64 rank = ((log & I3200_ECCERRLOG_RANK_BITS) >>
+                I3200_ECCERRLOG_RANK_SHIFT);
+        return rank | (channel * I3200_RANKS_PER_CHANNEL);
+}
+
+enum i3200_chips {
+        I3200 = 0,
+};
+
+struct i3200_dev_info {
+        const char *ctl_name;
+};
+
+struct i3200_error_info {
+        u16 errsts;
+        u16 errsts2;
+        u64 eccerrlog[I3200_CHANNELS];
+};
+
+static const struct i3200_dev_info i3200_devs[] = {
+        [I3200] = {
+                .ctl_name = "i3200"
+        },
+};
+
+static struct pci_dev *mci_pdev;
+static int i3200_registered = 1;
+
+
+static void i3200_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, I3200_ERRSTS, I3200_ERRSTS_BITS,
+                I3200_ERRSTS_BITS);
+}
+
+static void i3200_get_and_clear_error_info(struct mem_ctl_info *mci,
+                struct i3200_error_info *info)
+{
+        struct pci_dev *pdev;
+        struct i3200_priv *priv = mci->pvt_info;
+        void __iomem *window = priv->window;
+
+        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, I3200_ERRSTS, &info->errsts);
+        if (!(info->errsts & I3200_ERRSTS_BITS))
+                return;
+
+        info->eccerrlog[0] = readq(window + I3200_C0ECCERRLOG);
+        if (nr_channels == 2)
+                info->eccerrlog[1] = readq(window + I3200_C1ECCERRLOG);
+
+        pci_read_config_word(pdev, I3200_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) & I3200_ERRSTS_BITS) {
+                info->eccerrlog[0] = readq(window + I3200_C0ECCERRLOG);
+                if (nr_channels == 2)
+                        info->eccerrlog[1] = readq(window + I3200_C1ECCERRLOG);
+        }
+
+        i3200_clear_error_info(mci);
+}
+
+static void i3200_process_error_info(struct mem_ctl_info *mci,
+                struct i3200_error_info *info)
+{
+        int channel;
+        u64 log;
+
+        if (!(info->errsts & I3200_ERRSTS_BITS))
+                return;
+
+        if ((info->errsts ^ info->errsts2) & I3200_ERRSTS_BITS) {
+                edac_mc_handle_ce_no_info(mci, "UE overwrote CE");
+                info->errsts = info->errsts2;
+        }
+
+        for (channel = 0; channel < nr_channels; channel++) {
+                log = info->eccerrlog[channel];
+                if (log & I3200_ECCERRLOG_UE) {
+                        edac_mc_handle_ue(mci, 0, 0,
+                                eccerrlog_row(channel, log),
+                                "i3200 UE");
+                } else if (log & I3200_ECCERRLOG_CE) {
+                        edac_mc_handle_ce(mci, 0, 0,
+                                eccerrlog_syndrome(log),
+                                eccerrlog_row(channel, log), 0,
+                                "i3200 CE");
+                }
+        }
+}
+
+static void i3200_check(struct mem_ctl_info *mci)
+{
+        struct i3200_error_info info;
+
+        debugf1("MC%d: %s()\n", mci->mc_idx, __func__);
+        i3200_get_and_clear_error_info(mci, &info);
+        i3200_process_error_info(mci, &info);
+}
+
+
+void __iomem *i3200_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, I3200_MCHBAR_LOW, &u.mchbar_low);
+        pci_read_config_dword(pdev, I3200_MCHBAR_HIGH, &u.mchbar_high);
+        u.mchbar &= I3200_MCHBAR_MASK;
+
+        if (u.mchbar != (resource_size_t)u.mchbar) {
+                printk(KERN_ERR
+                        "i3200: mmio space beyond accessible range (0x%llx)\n",
+                        (unsigned long long)u.mchbar);
+                return NULL;
+        }
+
+        window = ioremap_nocache(u.mchbar, I3200_MMR_WINDOW_SIZE);
+        if (!window)
+                printk(KERN_ERR "i3200: cannot map mmio space at 0x%llx\n",
+                        (unsigned long long)u.mchbar);
+
+        return window;
+}
+
+
+static void i3200_get_drbs(void __iomem *window,
+        u16 drbs[I3200_CHANNELS][I3200_RANKS_PER_CHANNEL])
+{
+        int i;
+
+        for (i = 0; i < I3200_RANKS_PER_CHANNEL; i++) {
+                drbs[0][i] = readw(window + I3200_C0DRB + 2*i) & I3200_DRB_MASK;
+                drbs[1][i] = readw(window + I3200_C1DRB + 2*i) & I3200_DRB_MASK;
+        }
+}
+
+static bool i3200_is_stacked(struct pci_dev *pdev,
+        u16 drbs[I3200_CHANNELS][I3200_RANKS_PER_CHANNEL])
+{
+        u16 tom;
+
+        pci_read_config_word(pdev, I3200_TOM, &tom);
+        tom &= I3200_TOM_MASK;
+
+        return drbs[I3200_CHANNELS - 1][I3200_RANKS_PER_CHANNEL - 1] == tom;
+}
+
+static unsigned long drb_to_nr_pages(
+        u16 drbs[I3200_CHANNELS][I3200_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][I3200_RANKS_PER_CHANNEL - 1])
+                n -= drbs[0][I3200_RANKS_PER_CHANNEL - 1];
+
+        n <<= (I3200_DRB_SHIFT - PAGE_SHIFT);
+        return n;
+}
+
+static int i3200_probe1(struct pci_dev *pdev, int dev_idx)
+{
+        int rc;
+        int i;
+        struct mem_ctl_info *mci = NULL;
+        unsigned long last_page;
+        u16 drbs[I3200_CHANNELS][I3200_RANKS_PER_CHANNEL];
+        bool stacked;
+        void __iomem *window;
+        struct i3200_priv *priv;
+
+        debugf0("MC: %s()\n", __func__);
+
+        window = i3200_map_mchbar(pdev);
+        if (!window)
+                return -ENODEV;
+
+        i3200_get_drbs(window, drbs);
+        nr_channels = how_many_channels(pdev);
+
+        mci = edac_mc_alloc(sizeof(struct i3200_priv), I3200_RANKS,
+                nr_channels, 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 = I3200_REVISION;
+        mci->ctl_name = i3200_devs[dev_idx].ctl_name;
+        mci->dev_name = pci_name(pdev);
+        mci->edac_check = i3200_check;
+        mci->ctl_page_to_phys = NULL;
+        priv = mci->pvt_info;
+        priv->window = window;
+
+        stacked = i3200_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 / I3200_RANKS_PER_CHANNEL,
+                        i % I3200_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;
+        }
+
+        i3200_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 i3200_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 = i3200_probe1(pdev, ent->driver_data);
+        if (!mci_pdev)
+                mci_pdev = pci_dev_get(pdev);
+
+        return rc;
+}
+
+static void __devexit i3200_remove_one(struct pci_dev *pdev)
+{
+        struct mem_ctl_info *mci;
+        struct i3200_priv *priv;
+
+        debugf0("%s()\n", __func__);
+
+        mci = edac_mc_del_mc(&pdev->dev);
+        if (!mci)
+                return;
+
+        priv = mci->pvt_info;
+        iounmap(priv->window);
+
+        edac_mc_free(mci);
+}
+
+static const struct pci_device_id i3200_pci_tbl[] __devinitdata = {
+        {
+                PCI_VEND_DEV(INTEL, 3200_HB), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+                I3200},
+        {
+                0,
+        }            /* 0 terminated list. */
+};
+
+MODULE_DEVICE_TABLE(pci, i3200_pci_tbl);
+
+static struct pci_driver i3200_driver = {
+        .name = EDAC_MOD_STR,
+        .probe = i3200_init_one,
+        .remove = __devexit_p(i3200_remove_one),
+        .id_table = i3200_pci_tbl,
+};
+
+static int __init i3200_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(&i3200_driver);
+        if (pci_rc < 0)
+                goto fail0;
+
+        if (!mci_pdev) {
+                i3200_registered = 0;
+                mci_pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
+                                PCI_DEVICE_ID_INTEL_3200_HB, NULL);
+                if (!mci_pdev) {
+                        debugf0("i3200 pci_get_device fail\n");
+                        pci_rc = -ENODEV;
+                        goto fail1;
+                }
+
+                pci_rc = i3200_init_one(mci_pdev, i3200_pci_tbl);
+                if (pci_rc < 0) {
+                        debugf0("i3200 init fail\n");
+                        pci_rc = -ENODEV;
+                        goto fail1;
+                }
+        }
+
+        return 0;
+
+fail1:
+        pci_unregister_driver(&i3200_driver);
+
+fail0:
+        if (mci_pdev)
+                pci_dev_put(mci_pdev);
+
+        return pci_rc;
+}
+
+static void __exit i3200_exit(void)
+{
+        debugf3("MC: %s()\n", __func__);
+
+        pci_unregister_driver(&i3200_driver);
+        if (!i3200_registered) {
+                i3200_remove_one(mci_pdev);
+                pci_dev_put(mci_pdev);
+        }
+}
+
+module_init(i3200_init);
+module_exit(i3200_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Akamai Technologies, Inc.");
+MODULE_DESCRIPTION("MC support for Intel 3200 memory hub controllers");
+
+module_param(edac_op_state, int, 0444);
+MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");