[PATCH] EDAC: drivers for Radisys 82600

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/edac/r82600_edac.c

@@ -0,0 +1,407 @@
+/*
+ * Radisys 82600 Embedded chipset Memory Controller kernel module
+ * (C) 2005 EADS Astrium
+ * This file may be distributed under the terms of the
+ * GNU General Public License.
+ *
+ * Written by Tim Small <tim@buttersideup.com>, based on work by Thayne
+ * Harbaugh, Dan Hollis <goemon at anime dot net> and others.
+ *
+ * $Id: edac_r82600.c,v 1.1.2.6 2005/10/05 00:43:44 dsp_llnl Exp $
+ *
+ * Written with reference to 82600 High Integration Dual PCI System
+ * Controller Data Book:
+ * http://www.radisys.com/files/support_downloads/007-01277-0002.82600DataBook.pdf
+ * references to this document given in []
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+
+#include <linux/slab.h>
+
+#include "edac_mc.h"
+
+/* Radisys say "The 82600 integrates a main memory SDRAM controller that
+ * supports up to four banks of memory. The four banks can support a mix of
+ * sizes of 64 bit wide (72 bits with ECC) Synchronous DRAM (SDRAM) DIMMs,
+ * each of which can be any size from 16MB to 512MB. Both registered (control
+ * signals buffered) and unbuffered DIMM types are supported. Mixing of
+ * registered and unbuffered DIMMs as well as mixing of ECC and non-ECC DIMMs
+ * is not allowed. The 82600 SDRAM interface operates at the same frequency as
+ * the CPU bus, 66MHz, 100MHz or 133MHz."
+ */
+
+#define R82600_NR_CSROWS 4
+#define R82600_NR_CHANS  1
+#define R82600_NR_DIMMS  4
+
+#define R82600_BRIDGE_ID  0x8200
+
+/* Radisys 82600 register addresses - device 0 function 0 - PCI bridge */
+#define R82600_DRAMC	0x57	/* Various SDRAM related control bits
+				 * all bits are R/W
+				 *
+				 * 7    SDRAM ISA Hole Enable
+				 * 6    Flash Page Mode Enable
+				 * 5    ECC Enable: 1=ECC 0=noECC
+				 * 4    DRAM DIMM Type: 1=
+				 * 3    BIOS Alias Disable
+				 * 2    SDRAM BIOS Flash Write Enable
+				 * 1:0  SDRAM Refresh Rate: 00=Disabled
+				 *          01=7.8usec (256Mbit SDRAMs)
+				 *          10=15.6us 11=125usec
+				 */
+
+#define R82600_SDRAMC	0x76	/* "SDRAM Control Register"
+				 * More SDRAM related control bits
+				 * all bits are R/W
+				 *
+				 * 15:8 Reserved.
+				 *
+				 * 7:5  Special SDRAM Mode Select
+				 *
+				 * 4    Force ECC
+				 *
+				 *        1=Drive ECC bits to 0 during
+				 *          write cycles (i.e. ECC test mode)
+				 *
+				 *        0=Normal ECC functioning
+				 *
+				 * 3    Enhanced Paging Enable
+				 *
+				 * 2    CAS# Latency 0=3clks 1=2clks
+				 *
+				 * 1    RAS# to CAS# Delay 0=3 1=2
+				 *
+				 * 0    RAS# Precharge     0=3 1=2
+				 */
+
+#define R82600_EAP	0x80	/* ECC Error Address Pointer Register
+				 *
+				 * 31    Disable Hardware Scrubbing (RW)
+				 *        0=Scrub on corrected read
+				 *        1=Don't scrub on corrected read
+				 *
+				 * 30:12 Error Address Pointer (RO)
+				 *        Upper 19 bits of error address
+				 *
+				 * 11:4  Syndrome Bits (RO)
+				 *
+				 * 3     BSERR# on multibit error (RW)
+				 *        1=enable 0=disable
+				 *
+				 * 2     NMI on Single Bit Eror (RW)
+				 *        1=NMI triggered by SBE n.b. other
+				 *          prerequeists
+				 *        0=NMI not triggered
+				 *
+				 * 1     MBE (R/WC)
+				 *        read 1=MBE at EAP (see above)
+				 *        read 0=no MBE, or SBE occurred first
+				 *        write 1=Clear MBE status (must also
+				 *          clear SBE)
+				 *        write 0=NOP
+				 *
+				 * 1     SBE (R/WC)
+				 *        read 1=SBE at EAP (see above)
+				 *        read 0=no SBE, or MBE occurred first
+				 *        write 1=Clear SBE status (must also
+				 *          clear MBE)
+				 *        write 0=NOP
+				 */
+
+#define R82600_DRBA	0x60	/* + 0x60..0x63 SDRAM Row Boundry Address
+				 *  Registers
+				 *
+				 * 7:0  Address lines 30:24 - upper limit of
+				 * each row [p57]
+				 */
+
+struct r82600_error_info {
+	u32 eapr;
+};
+
+
+static unsigned int disable_hardware_scrub = 0;
+
+
+static void r82600_get_error_info (struct mem_ctl_info *mci,
+		struct r82600_error_info *info)
+{
+	pci_read_config_dword(mci->pdev, R82600_EAP, &info->eapr);
+
+	if (info->eapr & BIT(0))
+		/* Clear error to allow next error to be reported [p.62] */
+		pci_write_bits32(mci->pdev, R82600_EAP,
+				   ((u32) BIT(0) & (u32) BIT(1)),
+				   ((u32) BIT(0) & (u32) BIT(1)));
+
+	if (info->eapr & BIT(1))
+		/* Clear error to allow next error to be reported [p.62] */
+		pci_write_bits32(mci->pdev, R82600_EAP,
+				   ((u32) BIT(0) & (u32) BIT(1)),
+				   ((u32) BIT(0) & (u32) BIT(1)));
+}
+
+
+static int r82600_process_error_info (struct mem_ctl_info *mci,
+		struct r82600_error_info *info, int handle_errors)
+{
+	int error_found;
+	u32 eapaddr, page;
+	u32 syndrome;
+
+	error_found = 0;
+
+	/* bits 30:12 store the upper 19 bits of the 32 bit error address */
+	eapaddr = ((info->eapr >> 12) & 0x7FFF) << 13;
+	/* Syndrome in bits 11:4 [p.62]       */
+	syndrome = (info->eapr >> 4) & 0xFF;
+
+	/* the R82600 reports at less than page *
+	 * granularity (upper 19 bits only)     */
+	page = eapaddr >> PAGE_SHIFT;
+
+	if (info->eapr & BIT(0)) { 	/* CE? */
+		error_found = 1;
+
+		if (handle_errors)
+			edac_mc_handle_ce(
+			    mci, page, 0,	/* not avail */
+			    syndrome,
+			    edac_mc_find_csrow_by_page(mci, page),
+			    0,	/* channel */
+			    mci->ctl_name);
+	}
+
+	if (info->eapr & BIT(1)) { 	/* UE? */
+		error_found = 1;
+
+		if (handle_errors)
+			/* 82600 doesn't give enough info */
+			edac_mc_handle_ue(mci, page, 0,
+			    edac_mc_find_csrow_by_page(mci, page),
+			    mci->ctl_name);
+	}
+
+	return error_found;
+}
+
+static void r82600_check(struct mem_ctl_info *mci)
+{
+	struct r82600_error_info info;
+
+	debugf1("MC%d: " __FILE__ ": %s()\n", mci->mc_idx, __func__);
+	r82600_get_error_info(mci, &info);
+	r82600_process_error_info(mci, &info, 1);
+}
+
+static int r82600_probe1(struct pci_dev *pdev, int dev_idx)
+{
+	int rc = -ENODEV;
+	int index;
+	struct mem_ctl_info *mci = NULL;
+	u8 dramcr;
+	u32 ecc_on;
+	u32 reg_sdram;
+	u32 eapr;
+	u32 scrub_disabled;
+	u32 sdram_refresh_rate;
+	u32 row_high_limit_last = 0;
+	u32 eap_init_bits;
+
+	debugf0("MC: " __FILE__ ": %s()\n", __func__);
+
+
+	pci_read_config_byte(pdev, R82600_DRAMC, &dramcr);
+	pci_read_config_dword(pdev, R82600_EAP, &eapr);
+
+	ecc_on = dramcr & BIT(5);
+	reg_sdram = dramcr & BIT(4);
+	scrub_disabled = eapr & BIT(31);
+	sdram_refresh_rate = dramcr & (BIT(0) | BIT(1));
+
+	debugf2("MC: " __FILE__ ": %s(): sdram refresh rate = %#0x\n",
+		__func__, sdram_refresh_rate);
+
+	debugf2("MC: " __FILE__ ": %s(): DRAMC register = %#0x\n", __func__,
+		dramcr);
+
+	mci = edac_mc_alloc(0, R82600_NR_CSROWS, R82600_NR_CHANS);
+
+	if (mci == NULL) {
+		rc = -ENOMEM;
+		goto fail;
+	}
+
+	debugf0("MC: " __FILE__ ": %s(): mci = %p\n", __func__, mci);
+
+	mci->pdev = pdev;
+	mci->mtype_cap = MEM_FLAG_RDDR | MEM_FLAG_DDR;
+
+	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
+	/* FIXME try to work out if the chip leads have been                 *
+	 * used for COM2 instead on this board? [MA6?]       MAYBE:          */
+
+	/* On the R82600, the pins for memory bits 72:65 - i.e. the   *
+	 * EC bits are shared with the pins for COM2 (!), so if COM2  *
+	 * is enabled, we assume COM2 is wired up, and thus no EDAC   *
+	 * is possible.                                               */
+	mci->edac_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
+	if (ecc_on) {
+		if (scrub_disabled)
+			debugf3("MC: " __FILE__ ": %s(): mci = %p - "
+				"Scrubbing disabled! EAP: %#0x\n", __func__,
+				mci, eapr);
+	} else
+		mci->edac_cap = EDAC_FLAG_NONE;
+
+	mci->mod_name = BS_MOD_STR;
+	mci->mod_ver = "$Revision: 1.1.2.6 $";
+	mci->ctl_name = "R82600";
+	mci->edac_check = r82600_check;
+	mci->ctl_page_to_phys = NULL;
+
+	for (index = 0; index < mci->nr_csrows; index++) {
+		struct csrow_info *csrow = &mci->csrows[index];
+		u8 drbar;	/* sDram Row Boundry Address Register */
+		u32 row_high_limit;
+		u32 row_base;
+
+		/* find the DRAM Chip Select Base address and mask */
+		pci_read_config_byte(mci->pdev, R82600_DRBA + index, &drbar);
+
+		debugf1("MC%d: " __FILE__ ": %s() Row=%d DRBA = %#0x\n",
+			mci->mc_idx, __func__, index, drbar);
+
+		row_high_limit = ((u32) drbar << 24);
+/*		row_high_limit = ((u32)drbar << 24) | 0xffffffUL; */
+
+		debugf1("MC%d: " __FILE__ ": %s() Row=%d, "
+			"Boundry Address=%#0x, Last = %#0x \n",
+			mci->mc_idx, __func__, index, row_high_limit,
+			row_high_limit_last);
+
+		/* Empty row [p.57] */
+		if (row_high_limit == row_high_limit_last)
+			continue;
+
+		row_base = row_high_limit_last;
+
+		csrow->first_page = row_base >> PAGE_SHIFT;
+		csrow->last_page = (row_high_limit >> PAGE_SHIFT) - 1;
+		csrow->nr_pages = csrow->last_page - csrow->first_page + 1;
+		/* Error address is top 19 bits - so granularity is      *
+		 * 14 bits                                               */
+		csrow->grain = 1 << 14;
+		csrow->mtype = reg_sdram ? MEM_RDDR : MEM_DDR;
+		/* FIXME - check that this is unknowable with this chipset */
+		csrow->dtype = DEV_UNKNOWN;
+
+		/* Mode is global on 82600 */
+		csrow->edac_mode = ecc_on ? EDAC_SECDED : EDAC_NONE;
+		row_high_limit_last = row_high_limit;
+	}
+
+	/* clear counters */
+	/* FIXME should we? */
+
+	if (edac_mc_add_mc(mci)) {
+		debugf3("MC: " __FILE__
+			": %s(): failed edac_mc_add_mc()\n", __func__);
+		goto fail;
+	}
+
+	/* get this far and it's successful */
+
+	/* Clear error flags to allow next error to be reported [p.62] */
+	/* Test systems seem to always have the UE flag raised on boot */
+
+	eap_init_bits = BIT(0) & BIT(1);
+	if (disable_hardware_scrub) {
+		eap_init_bits |= BIT(31);
+		debugf3("MC: " __FILE__ ": %s(): Disabling Hardware Scrub "
+			"(scrub on error)\n", __func__);
+	}
+
+	pci_write_bits32(mci->pdev, R82600_EAP, eap_init_bits,
+			 eap_init_bits);
+
+	debugf3("MC: " __FILE__ ": %s(): success\n", __func__);
+	return 0;
+
+fail:
+	if (mci)
+		edac_mc_free(mci);
+
+	return rc;
+}
+
+/* returns count (>= 0), or negative on error */
+static int __devinit r82600_init_one(struct pci_dev *pdev,
+				     const struct pci_device_id *ent)
+{
+	debugf0("MC: " __FILE__ ": %s()\n", __func__);
+
+	/* don't need to call pci_device_enable() */
+	return r82600_probe1(pdev, ent->driver_data);
+}
+
+
+static void __devexit r82600_remove_one(struct pci_dev *pdev)
+{
+	struct mem_ctl_info *mci;
+
+	debugf0(__FILE__ ": %s()\n", __func__);
+
+	if (((mci = edac_mc_find_mci_by_pdev(pdev)) != NULL) &&
+	    !edac_mc_del_mc(mci))
+		edac_mc_free(mci);
+}
+
+
+static const struct pci_device_id r82600_pci_tbl[] __devinitdata = {
+	{PCI_DEVICE(PCI_VENDOR_ID_RADISYS, R82600_BRIDGE_ID)},
+	{0,}			/* 0 terminated list. */
+};
+
+MODULE_DEVICE_TABLE(pci, r82600_pci_tbl);
+
+
+static struct pci_driver r82600_driver = {
+	.name = BS_MOD_STR,
+	.probe = r82600_init_one,
+	.remove = __devexit_p(r82600_remove_one),
+	.id_table = r82600_pci_tbl,
+};
+
+
+int __init r82600_init(void)
+{
+	return pci_register_driver(&r82600_driver);
+}
+
+
+static void __exit r82600_exit(void)
+{
+	pci_unregister_driver(&r82600_driver);
+}
+
+
+module_init(r82600_init);
+module_exit(r82600_exit);
+
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Tim Small <tim@buttersideup.com> - WPAD Ltd. "
+	      "on behalf of EADS Astrium");
+MODULE_DESCRIPTION("MC support for Radisys 82600 memory controllers");
+
+module_param(disable_hardware_scrub, bool, 0644);
+MODULE_PARM_DESC(disable_hardware_scrub,
+		 "If set, disable the chipset's automatic scrub for CEs");