// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2008 Nuovation System Designs, LLC
* Grant Erickson <gerickson@nuovations.com>
*/
#include <linux/edac.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/types.h>
#include <asm/dcr.h>
#include "edac_module.h"
#include "ppc4xx_edac.h"
/*
* This file implements a driver for monitoring and handling events
* associated with the IMB DDR2 ECC controller found in the AMCC/IBM
* 405EX[r], 440SP, 440SPe, 460EX, 460GT and 460SX.
*
* As realized in the 405EX[r], this controller features:
*
* - Support for registered- and non-registered DDR1 and DDR2 memory.
* - 32-bit or 16-bit memory interface with optional ECC.
*
* o ECC support includes:
*
* - 4-bit SEC/DED
* - Aligned-nibble error detect
* - Bypass mode
*
* - Two (2) memory banks/ranks.
* - Up to 1 GiB per bank/rank in 32-bit mode and up to 512 MiB per
* bank/rank in 16-bit mode.
*
* As realized in the 440SP and 440SPe, this controller changes/adds:
*
* - 64-bit or 32-bit memory interface with optional ECC.
*
* o ECC support includes:
*
* - 8-bit SEC/DED
* - Aligned-nibble error detect
* - Bypass mode
*
* - Up to 4 GiB per bank/rank in 64-bit mode and up to 2 GiB
* per bank/rank in 32-bit mode.
*
* As realized in the 460EX and 460GT, this controller changes/adds:
*
* - 64-bit or 32-bit memory interface with optional ECC.
*
* o ECC support includes:
*
* - 8-bit SEC/DED
* - Aligned-nibble error detect
* - Bypass mode
*
* - Four (4) memory banks/ranks.
* - Up to 16 GiB per bank/rank in 64-bit mode and up to 8 GiB
* per bank/rank in 32-bit mode.
*
* At present, this driver has ONLY been tested against the controller
* realization in the 405EX[r] on the AMCC Kilauea and Haleakala
* boards (256 MiB w/o ECC memory soldered onto the board) and a
* proprietary board based on those designs (128 MiB ECC memory, also
* soldered onto the board).
*
* Dynamic feature detection and handling needs to be added for the
* other realizations of this controller listed above.
*
* Eventually, this driver will likely be adapted to the above variant
* realizations of this controller as well as broken apart to handle
* the other known ECC-capable controllers prevalent in other 4xx
* processors:
*
* - IBM SDRAM (405GP, 405CR and 405EP) "ibm,sdram-4xx"
* - IBM DDR1 (440GP, 440GX, 440EP and 440GR) "ibm,sdram-4xx-ddr"
* - Denali DDR1/DDR2 (440EPX and 440GRX) "denali,sdram-4xx-ddr2"
*
* For this controller, unfortunately, correctable errors report
* nothing more than the beat/cycle and byte/lane the correction
* occurred on and the check bit group that covered the error.
*
* In contrast, uncorrectable errors also report the failing address,
* the bus master and the transaction direction (i.e. read or write)
*
* Regardless of whether the error is a CE or a UE, we report the
* following pieces of information in the driver-unique message to the
* EDAC subsystem:
*
* - Device tree path
* - Bank(s)
* - Check bit error group
* - Beat(s)/lane(s)
*/
/* Preprocessor Definitions */
#define EDAC_OPSTATE_INT_STR "interrupt"
#define EDAC_OPSTATE_POLL_STR "polled"
#define EDAC_OPSTATE_UNKNOWN_STR "unknown"
#define PPC4XX_EDAC_MODULE_NAME "ppc4xx_edac"
#define PPC4XX_EDAC_MODULE_REVISION "v1.0.0"
#define PPC4XX_EDAC_MESSAGE_SIZE 256
/*
* Kernel logging without an EDAC instance
*/
#define ppc4xx_edac_printk(level, fmt, arg...) \
edac_printk(level, "PPC4xx MC", fmt, ##arg)
/*
* Kernel logging with an EDAC instance
*/
#define ppc4xx_edac_mc_printk(level, mci, fmt, arg...) \
edac_mc_chipset_printk(mci, level, "PPC4xx", fmt, ##arg)
/*
* Macros to convert bank configuration size enumerations into MiB and
* page values.
*/
#define SDRAM_MBCF_SZ_MiB_MIN 4
#define SDRAM_MBCF_SZ_TO_MiB(n) (SDRAM_MBCF_SZ_MiB_MIN \
<< (SDRAM_MBCF_SZ_DECODE(n)))
#define SDRAM_MBCF_SZ_TO_PAGES(n) (SDRAM_MBCF_SZ_MiB_MIN \
<< (20 - PAGE_SHIFT + \
SDRAM_MBCF_SZ_DECODE(n)))
/*
* The ibm,sdram-4xx-ddr2 Device Control Registers (DCRs) are
* indirectly accessed and have a base and length defined by the
* device tree. The base can be anything; however, we expect the
* length to be precisely two registers, the first for the address
* window and the second for the data window.
*/
#define SDRAM_DCR_RESOURCE_LEN 2
#define SDRAM_DCR_ADDR_OFFSET 0
#define SDRAM_DCR_DATA_OFFSET 1
/*
* Device tree interrupt indices
*/
#define INTMAP_ECCDED_INDEX 0 /* Double-bit Error Detect */
#define INTMAP_ECCSEC_INDEX 1 /* Single-bit Error Correct */
/* Type Definitions */
/*
* PPC4xx SDRAM memory controller private instance data
*/
struct ppc4xx_edac_pdata {
dcr_host_t dcr_host; /* Indirect DCR address/data window mapping */
struct {
int sec; /* Single-bit correctable error IRQ assigned */
int ded; /* Double-bit detectable error IRQ assigned */
} irqs;
};
/*
* Various status data gathered and manipulated when checking and
* reporting ECC status.
*/
struct ppc4xx_ecc_status {
u32 ecces;
u32 besr;
u32 bearh;
u32 bearl;
u32 wmirq;
};
/* Global Variables */
/*
* Device tree node type and compatible tuples this driver can match
* on.
*/
static const struct of_device_id ppc4xx_edac_match[] = {
{
.compatible = "ibm,sdram-4xx-ddr2"
},
{ }
};
MODULE_DEVICE_TABLE(of, ppc4xx_edac_match);
/*
* TODO: The row and channel parameters likely need to be dynamically
* set based on the aforementioned variant controller realizations.
*/
static const unsigned ppc4xx_edac_nr_csrows = 2;
static const unsigned ppc4xx_edac_nr_chans = 1;
/*
* Strings associated with PLB master IDs capable of being posted in
* SDRAM_BESR or SDRAM_WMIRQ on uncorrectable ECC errors.
*/
static const char * const ppc4xx_plb_masters[9] = {
[SDRAM_PLB_M0ID_ICU] = "ICU",
[SDRAM_PLB_M0ID_PCIE0] = "PCI-E 0",
[SDRAM_PLB_M0ID_PCIE1] = "PCI-E 1",
[SDRAM_PLB_M0ID_DMA] = "DMA",
[SDRAM_PLB_M0ID_DCU] = "DCU",
[SDRAM_PLB_M0ID_OPB] = "OPB",
[SDRAM_PLB_M0ID_MAL] = "MAL",
[SDRAM_PLB_M0ID_SEC] = "SEC",
[SDRAM_PLB_M0ID_AHB] = "AHB"
};
/**
* mfsdram - read and return controller register data
* @dcr_host: A pointer to the DCR mapping.
* @idcr_n: The indirect DCR register to read.
*
* This routine reads and returns the data associated with the
* controller's specified indirect DCR register.
*
* Returns the read data.
*/
static inline u32
mfsdram(const dcr_host_t *dcr_host, unsigned int idcr_n)
{
return __mfdcri(dcr_host->base + SDRAM_DCR_ADDR_OFFSET,
dcr_host->base + SDRAM_DCR_DATA_OFFSET,
idcr_n);
}
/**
* mtsdram - write controller register data
* @dcr_host: A pointer to the DCR mapping.
* @idcr_n: The indirect DCR register to write.
* @value: The data to write.
*
* This routine writes the provided data to the controller's specified
* indirect DCR register.
*/
static inline void
mtsdram(const dcr_host_t *dcr_host, unsigned int idcr_n, u32 value)
{
return __mtdcri(dcr_host->base + SDRAM_DCR_ADDR_OFFSET,
dcr_host->base + SDRAM_DCR_DATA_OFFSET,
idcr_n,
value);
}
/**
* ppc4xx_edac_check_bank_error - check a bank for an ECC bank error
* @status: A pointer to the ECC status structure to check for an
* ECC bank error.
* @bank: The bank to check for an ECC error.
*
* This routine determines whether the specified bank has an ECC
* error.
*
* Returns true if the specified bank has an ECC error; otherwise,
* false.
*/
static bool
ppc4xx_edac_check_bank_error(const struct ppc4xx_ecc_status *status,
unsigned int bank)
{
switch (bank) {
case 0:
return status->ecces & SDRAM_ECCES_BK0ER;
case 1:
return status->ecces & SDRAM_ECCES_BK1ER;
default:
return false;
}
}
/**
* ppc4xx_edac_generate_bank_message - generate interpretted bank status message
* @mci: A pointer to the EDAC memory controller instance associated
* with the bank message being generated.
* @status: A pointer to the ECC status structure to generate the
* message from.
* @buffer: A pointer to the buffer in which to generate the
* message.
* @size: The size, in bytes, of space available in buffer.
*
* This routine generates to the provided buffer the portion of the
* driver-unique report message associated with the ECCESS[BKNER]
* field of the specified ECC status.
*
* Returns the number of characters generated on success; otherwise, <
* 0 on error.
*/
static int
ppc4xx_edac_generate_bank_message(const struct mem_ctl_info *mci,
const struct ppc4xx_ecc_status *status,
char *buffer,
size_t size)
{
int n, total = 0;
unsigned int row, rows;
n = snprintf(buffer, size, "%s: Banks: ", mci->dev_name);
if (n < 0 || n >= size)
goto fail;
buffer += n;
size -= n;
total += n;
for (rows = 0, row = 0; row < mci->nr_csrows; row++) {
if (ppc4xx_edac_check_bank_error(status, row)) {
n = snprintf(buffer, size, "%s%u",
(rows++ ? ", " : ""), row);
if (n < 0 || n >= size)
goto fail;
buffer += n;
size -= n;
total += n;
}
}
n = snprintf(buffer, size, "%s; ", rows ? "" : "None");
if (n < 0 || n >= size)
goto fail;
buffer += n;
size -= n;
total += n;
fail:
return total;
}
/**
* ppc4xx_edac_generate_checkbit_message - generate interpretted checkbit message
* @mci: A pointer to the EDAC memory controller instance associated
* with the checkbit message being generated.
* @status: A pointer to the ECC status structure to generate the
* message from.
* @buffer: A pointer to the buffer in which to generate the
* message.
* @size: The size, in bytes, of space available in buffer.
*
* This routine generates to the provided buffer the portion of the
* driver-unique report message associated with the ECCESS[CKBER]
* field of the specified ECC status.
*
* Returns the number of characters generated on success; otherwise, <
* 0 on error.
*/
static int
ppc4xx_edac_generate_checkbit_message(const struct mem_ctl_info *mci,
const struct ppc4xx_ecc_status *status,
char *buffer,
size_t size)
{
const struct ppc4xx_edac_pdata *pdata = mci->pvt_info;
const char *ckber = NULL;
switch (status->ecces & SDRAM_ECCES_CKBER_MASK) {
case SDRAM_ECCES_CKBER_NONE:
ckber = "None";
break;
case SDRAM_ECCES_CKBER_32_ECC_0_3:
ckber = "ECC0:3";
break;
case SDRAM_ECCES_CKBER_32_ECC_4_8:
switch (mfsdram(&pdata->dcr_host, SDRAM_MCOPT1) &
SDRAM_MCOPT1_WDTH_MASK) {
case SDRAM_MCOPT1_WDTH_16:
ckber = "ECC0:3";
break;
case SDRAM_MCOPT1_WDTH_32:
ckber = "ECC4:8";
break;
default:
ckber = "Unknown";
break;
}
break;
case SDRAM_ECCES_CKBER_32_ECC_0_8:
ckber = "ECC0:8";
break;
default:
ckber = "Unknown";
break;
}
return snprintf(buffer, size, "Checkbit Error: %s", ckber);
}
/**
* ppc4xx_edac_generate_lane_message - generate interpretted byte lane message
* @mci: A pointer to the EDAC memory controller instance associated
* with the byte lane message being generated.
* @status: A pointer to the ECC status structure to generate the
* message from.
* @buffer: A pointer to the buffer in which to generate the
* message.
* @size: The size, in bytes, of space available in buffer.
*
* This routine generates to the provided buffer the portion of the
* driver-unique report message associated with the ECCESS[BNCE]
* field of the specified ECC status.
*
* Returns the number of characters generated on success; otherwise, <
* 0 on error.
*/
static int
ppc4xx_edac_generate_lane_message(const struct mem_ctl_info *mci,
const struct ppc4xx_ecc_status *status,
char *buffer,
size_t size)
{
int n, total = 0;
unsigned int lane, lanes;
const unsigned int first_lane = 0;
const unsigned int lane_count = 16;
n = snprintf(buffer, size, "; Byte Lane Errors: ");
if (n < 0 || n >= size)
goto fail;
buffer += n;
size -= n;
total += n;
for (lanes = 0, lane = first_lane; lane < lane_count; lane++) {
if ((status->ecces & SDRAM_ECCES_BNCE_ENCODE(lane)) != 0) {
n = snprintf(buffer, size,
"%s%u",
(lanes++ ? ", " : ""), lane);
if (n < 0 || n >= size)
goto fail;
buffer += n;
size -= n;
total += n;
}
}
n = snprintf(buffer, size, "%s; ", lanes ? "" : "None");
if (n < 0 || n >= size)
goto fail;
buffer += n;
size -= n;
total += n;
fail:
return total;
}
/**
* ppc4xx_edac_generate_ecc_message - generate interpretted ECC status message
* @mci: A pointer to the EDAC memory controller instance associated
* with the ECCES message being generated.
* @status: A pointer to the ECC status structure to generate the
* message from.
* @buffer: A pointer to the buffer in which to generate the
* message.
* @size: The size, in bytes, of space available in buffer.
*
* This routine generates to the provided buffer the portion of the
* driver-unique report message associated with the ECCESS register of
* the specified ECC status.
*
* Returns the number of characters generated on success; otherwise, <
* 0 on error.
*/
static int
ppc4xx_edac_generate_ecc_message(const struct mem_ctl_info *mci,
const struct ppc4xx_ecc_status *status,
char *buffer,
size_t size)
{
int n, total = 0;
n = ppc4xx_edac_generate_bank_message(mci, status, buffer, size);
if (n < 0 || n >= size)
goto fail;
buffer += n;
size -= n;
total += n;
n = ppc4xx_edac_generate_checkbit_message(mci, status, buffer, size);
if (n < 0 || n >= size)
goto fail;
buffer += n;
size -= n;
total += n;
n = ppc4xx_edac_generate_lane_message(mci, status, buffer, size);
if (n < 0 || n >= size)
goto fail;
buffer += n;
size -= n;
total += n;
fail:
return total;
}
/**
* ppc4xx_edac_generate_plb_message - generate interpretted PLB status message
* @mci: A pointer to the EDAC memory controller instance associated
* with the PLB message being generated.
* @status: A pointer to the ECC status structure to generate the
* message from.
* @buffer: A pointer to the buffer in which to generate the
* message.
* @size: The size, in bytes, of space available in buffer.
*
* This routine generates to the provided buffer the portion of the
* driver-unique report message associated with the PLB-related BESR
* and/or WMIRQ registers of the specified ECC status.
*
* Returns the number of characters generated on success; otherwise, <
* 0 on error.
*/
static int
ppc4xx_edac_generate_plb_message(const struct mem_ctl_info *mci,
const struct ppc4xx_ecc_status *status,
char *buffer,
size_t size)
{
unsigned int master;
bool read;
if ((status->besr & SDRAM_BESR_MASK) == 0)
return 0;
if ((status->besr & SDRAM_BESR_M0ET_MASK) == SDRAM_BESR_M0ET_NONE)
return 0;
read = ((status->besr & SDRAM_BESR_M0RW_MASK) == SDRAM_BESR_M0RW_READ);
master = SDRAM_BESR_M0ID_DECODE(status->besr);
return snprintf(buffer, size,
"%s error w/ PLB master %u \"%s\"; ",
(read ? "Read" : "Write"),
master,
(((master >= SDRAM_PLB_M0ID_FIRST) &&
(master <= SDRAM_PLB_M0ID_LAST)) ?
ppc4xx_plb_masters[master] : "UNKNOWN"));
}
/**
* ppc4xx_edac_generate_message - generate interpretted status message
* @mci: A pointer to the EDAC memory controller instance associated
* with the driver-unique message being generated.
* @status: A pointer to the ECC status structure to generate the
* message from.
* @buffer: A pointer to the buffer in which to generate the
* message.
* @size: The size, in bytes, of space available in buffer.
*
* This routine generates to the provided buffer the driver-unique
* EDAC report message from the specified ECC status.
*/
static void
ppc4xx_edac_generate_message(const struct mem_ctl_info *mci,
const struct ppc4xx_ecc_status *status,
char *buffer,
size_t size)
{
int n;
if (buffer == NULL || size == 0)
return;
n = ppc4xx_edac_generate_ecc_message(mci, status, buffer, size);
if (n < 0 || n >= size)
return;
buffer += n;
size -= n;
ppc4xx_edac_generate_plb_message(mci, status, buffer, size);
}
#ifdef DEBUG
/**
* ppc4xx_ecc_dump_status - dump controller ECC status registers
* @mci: A pointer to the EDAC memory controller instance
* associated with the status being dumped.
* @status: A pointer to the ECC status structure to generate the
* dump from.
*
* This routine dumps to the kernel log buffer the raw and
* interpretted specified ECC status.
*/
static void
ppc4xx_ecc_dump_status(const struct mem_ctl_info *mci,
const struct ppc4xx_ecc_status *status)
{
char message[PPC4XX_EDAC_MESSAGE_SIZE];
ppc4xx_edac_generate_message(mci, status, message, sizeof(message));
ppc4xx_edac_mc_printk(KERN_INFO, mci,
"\n"
"\tECCES: 0x%08x\n"
"\tWMIRQ: 0x%08x\n"
"\tBESR: 0x%08x\n"
"\tBEAR: 0x%08x%08x\n"
"\t%s\n",
status->ecces,
status->wmirq,
status->besr,
status->bearh,
status->bearl,
message);
}
#endif /* DEBUG */
/**
* ppc4xx_ecc_get_status - get controller ECC status
* @mci: A pointer to the EDAC memory controller instance
* associated with the status being retrieved.
* @status: A pointer to the ECC status structure to populate the
* ECC status with.
*
* This routine reads and masks, as appropriate, all the relevant
* status registers that deal with ibm,sdram-4xx-ddr2 ECC errors.
* While we read all of them, for correctable errors, we only expect
* to deal with ECCES. For uncorrectable errors, we expect to deal
* with all of them.
*/
static void
ppc4xx_ecc_get_status(const struct mem_ctl_info *mci,
struct ppc4xx_ecc_status *status)
{
const struct ppc4xx_edac_pdata *pdata = mci->pvt_info;
const dcr_host_t *dcr_host = &pdata->dcr_host;
status->ecces = mfsdram(dcr_host, SDRAM_ECCES) & SDRAM_ECCES_MASK;
status->wmirq = mfsdram(dcr_host, SDRAM_WMIRQ) & SDRAM_WMIRQ_MASK;
status->besr = mfsdram(dcr_host, SDRAM_BESR) & SDRAM_BESR_MASK;
status->bearl = mfsdram(dcr_host, SDRAM_BEARL);
status->bearh = mfsdram(dcr_host, SDRAM_BEARH);
}
/**
* ppc4xx_ecc_clear_status - clear controller ECC status
* @mci: A pointer to the EDAC memory controller instance
* associated with the status being cleared.
* @status: A pointer to the ECC status structure containing the
* values to write to clear the ECC status.
*
* This routine clears--by writing the masked (as appropriate) status
* values back to--the status registers that deal with
* ibm,sdram-4xx-ddr2 ECC errors.
*/
static void
ppc4xx_ecc_clear_status(const struct mem_ctl_info *mci,
const struct ppc4xx_ecc_status *status)
{
const struct ppc4xx_edac_pdata *pdata = mci->pvt_info;
const dcr_host_t *dcr_host = &pdata->dcr_host;
mtsdram(dcr_host, SDRAM_ECCES, status->ecces & SDRAM_ECCES_MASK);
mtsdram(dcr_host, SDRAM_WMIRQ, status->wmirq & SDRAM_WMIRQ_MASK);
mtsdram(dcr_host, SDRAM_BESR, status->besr & SDRAM_BESR_MASK);
mtsdram(dcr_host, SDRAM_BEARL, 0);
mtsdram(dcr_host, SDRAM_BEARH, 0);
}
/**
* ppc4xx_edac_handle_ce - handle controller correctable ECC error (CE)
* @mci: A pointer to the EDAC memory controller instance
* associated with the correctable error being handled and reported.
* @status: A pointer to the ECC status structure associated with
* the correctable error being handled and reported.
*
* This routine handles an ibm,sdram-4xx-ddr2 controller ECC
* correctable error. Per the aforementioned discussion, there's not
* enough status available to use the full EDAC correctable error
* interface, so we just pass driver-unique message to the "no info"
* interface.
*/
static void
ppc4xx_edac_handle_ce(struct mem_ctl_info *mci,
const struct ppc4xx_ecc_status *status)
{
int row;
char message[PPC4XX_EDAC_MESSAGE_SIZE];
ppc4xx_edac_generate_message(mci, status, message, sizeof(message));
for (row = 0; row < mci->nr_csrows; row++)
if (ppc4xx_edac_check_bank_error(status, row))
edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
0, 0, 0,
row, 0, -1,
message, "");
}
/**
* ppc4xx_edac_handle_ue - handle controller uncorrectable ECC error (UE)
* @mci: A pointer to the EDAC memory controller instance
* associated with the uncorrectable error being handled and
* reported.
* @status: A pointer to the ECC status structure associated with
* the uncorrectable error being handled and reported.
*
* This routine handles an ibm,sdram-4xx-ddr2 controller ECC
* uncorrectable error.
*/
static void
ppc4xx_edac_handle_ue(struct mem_ctl_info *mci,
const struct ppc4xx_ecc_status *status)
{
const u64 bear = ((u64)status->bearh << 32 | status->bearl);
const unsigned long page = bear >> PAGE_SHIFT;
const unsigned long offset = bear & ~PAGE_MASK;
int row;
char message[PPC4XX_EDAC_MESSAGE_SIZE];
ppc4xx_edac_generate_message(mci, status, message, sizeof(message));
for (row = 0; row < mci->nr_csrows; row++)
if (ppc4xx_edac_check_bank_error(status, row))
edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
page, offset, 0,
row, 0, -1,
message, "");
}
/**
* ppc4xx_edac_check - check controller for ECC errors
* @mci: A pointer to the EDAC memory controller instance
* associated with the ibm,sdram-4xx-ddr2 controller being
* checked.
*
* This routine is used to check and post ECC errors and is called by
* both the EDAC polling thread and this driver's CE and UE interrupt
* handler.
*/
static void
ppc4xx_edac_check(struct mem_ctl_info *mci)
{
#ifdef DEBUG
static unsigned int count;
#endif
struct ppc4xx_ecc_status status;
ppc4xx_ecc_get_status(mci, &status);
#ifdef DEBUG
if (count++ % 30 == 0)
ppc4xx_ecc_dump_status(mci, &status);
#endif
if (status.ecces & SDRAM_ECCES_UE)
ppc4xx_edac_handle_ue(mci, &status);
if (status.ecces & SDRAM_ECCES_CE)
ppc4xx_edac_handle_ce(mci, &status);
ppc4xx_ecc_clear_status(mci, &status);
}
/**
* ppc4xx_edac_isr - SEC (CE) and DED (UE) interrupt service routine
* @irq: The virtual interrupt number being serviced.
* @dev_id: A pointer to the EDAC memory controller instance
* associated with the interrupt being handled.
*
* This routine implements the interrupt handler for both correctable
* (CE) and uncorrectable (UE) ECC errors for the ibm,sdram-4xx-ddr2
* controller. It simply calls through to the same routine used during
* polling to check, report and clear the ECC status.
*
* Unconditionally returns IRQ_HANDLED.
*/
static irqreturn_t
ppc4xx_edac_isr(int irq, void *dev_id)
{
struct mem_ctl_info *mci = dev_id;
ppc4xx_edac_check(mci);
return IRQ_HANDLED;
}
/**
* ppc4xx_edac_get_dtype - return the controller memory width
* @mcopt1: The 32-bit Memory Controller Option 1 register value
* currently set for the controller, from which the width
* is derived.
*
* This routine returns the EDAC device type width appropriate for the
* current controller configuration.
*
* TODO: This needs to be conditioned dynamically through feature
* flags or some such when other controller variants are supported as
* the 405EX[r] is 16-/32-bit and the others are 32-/64-bit with the
* 16- and 64-bit field definition/value/enumeration (b1) overloaded
* among them.
*
* Returns a device type width enumeration.
*/
static enum dev_type ppc4xx_edac_get_dtype(u32 mcopt1)
{
switch (mcopt1 & SDRAM_MCOPT1_WDTH_MASK) {
case SDRAM_MCOPT1_WDTH_16:
return DEV_X2;
case SDRAM_MCOPT1_WDTH_32:
return DEV_X4;
default:
return DEV_UNKNOWN;
}
}
/**
* ppc4xx_edac_get_mtype - return controller memory type
* @mcopt1: The 32-bit Memory Controller Option 1 register value
* currently set for the controller, from which the memory type
* is derived.
*
* This routine returns the EDAC memory type appropriate for the
* current controller configuration.
*
* Returns a memory type enumeration.
*/
static enum mem_type ppc4xx_edac_get_mtype(u32 mcopt1)
{
bool rden = ((mcopt1 & SDRAM_MCOPT1_RDEN_MASK) == SDRAM_MCOPT1_RDEN);
switch (mcopt1 & SDRAM_MCOPT1_DDR_TYPE_MASK) {
case SDRAM_MCOPT1_DDR2_TYPE:
return rden ? MEM_RDDR2 : MEM_DDR2;
case SDRAM_MCOPT1_DDR1_TYPE:
return rden ? MEM_RDDR : MEM_DDR;
default:
return MEM_UNKNOWN;
}
}
/**
* ppc4xx_edac_init_csrows - initialize driver instance rows
* @mci: A pointer to the EDAC memory controller instance
* associated with the ibm,sdram-4xx-ddr2 controller for which
* the csrows (i.e. banks/ranks) are being initialized.
* @mcopt1: The 32-bit Memory Controller Option 1 register value
* currently set for the controller, from which bank width
* and memory typ information is derived.
*
* This routine initializes the virtual "chip select rows" associated
* with the EDAC memory controller instance. An ibm,sdram-4xx-ddr2
* controller bank/rank is mapped to a row.
*
* Returns 0 if OK; otherwise, -EINVAL if the memory bank size
* configuration cannot be determined.
*/
static int ppc4xx_edac_init_csrows(struct mem_ctl_info *mci, u32 mcopt1)
{
const struct ppc4xx_edac_pdata *pdata = mci->pvt_info;
int status = 0;
enum mem_type mtype;
enum dev_type dtype;
enum edac_type edac_mode;
int row, j;
u32 mbxcf, size, nr_pages;
/* Establish the memory type and width */
mtype = ppc4xx_edac_get_mtype(mcopt1);
dtype = ppc4xx_edac_get_dtype(mcopt1);
/* Establish EDAC mode */
if (mci->edac_cap & EDAC_FLAG_SECDED)
edac_mode = EDAC_SECDED;
else if (mci->edac_cap & EDAC_FLAG_EC)
edac_mode = EDAC_EC;
else
edac_mode = EDAC_NONE;
/*
* Initialize each chip select row structure which correspond
* 1:1 with a controller bank/rank.
*/
for (row = 0; row < mci->nr_csrows; row++) {
struct csrow_info *csi = mci->csrows[row];
/*
* Get the configuration settings for this
* row/bank/rank and skip disabled banks.
*/
mbxcf = mfsdram(&pdata->dcr_host, SDRAM_MBXCF(row));
if ((mbxcf & SDRAM_MBCF_BE_MASK) != SDRAM_MBCF_BE_ENABLE)
continue;
/* Map the bank configuration size setting to pages. */
size = mbxcf & SDRAM_MBCF_SZ_MASK;
switch (size) {
case SDRAM_MBCF_SZ_4MB:
case SDRAM_MBCF_SZ_8MB:
case SDRAM_MBCF_SZ_16MB:
case SDRAM_MBCF_SZ_32MB:
case SDRAM_MBCF_SZ_64MB:
case SDRAM_MBCF_SZ_128MB:
case SDRAM_MBCF_SZ_256MB:
case SDRAM_MBCF_SZ_512MB:
case SDRAM_MBCF_SZ_1GB:
case SDRAM_MBCF_SZ_2GB:
case SDRAM_MBCF_SZ_4GB:
case SDRAM_MBCF_SZ_8GB:
nr_pages = SDRAM_MBCF_SZ_TO_PAGES(size);
break;
default:
ppc4xx_edac_mc_printk(KERN_ERR, mci,
"Unrecognized memory bank %d "
"size 0x%08x\n",
row, SDRAM_MBCF_SZ_DECODE(size));
status = -EINVAL;
goto done;
}
/*
* It's unclear exactly what grain should be set to
* here. The SDRAM_ECCES register allows resolution of
* an error down to a nibble which would potentially
* argue for a grain of '1' byte, even though we only
* know the associated address for uncorrectable
* errors. This value is not used at present for
* anything other than error reporting so getting it
* wrong should be of little consequence. Other
* possible values would be the PLB width (16), the
* page size (PAGE_SIZE) or the memory width (2 or 4).
*/
for (j = 0; j < csi->nr_channels; j++) {
struct dimm_info *dimm = csi->channels[j]->dimm;
dimm->nr_pages = nr_pages / csi->nr_channels;
dimm->grain = 1;
dimm->mtype = mtype;
dimm->dtype = dtype;
dimm->edac_mode = edac_mode;
}
}
done:
return status;
}
/**
* ppc4xx_edac_mc_init - initialize driver instance
* @mci: A pointer to the EDAC memory controller instance being
* initialized.
* @op: A pointer to the OpenFirmware device tree node associated
* with the controller this EDAC instance is bound to.
* @dcr_host: A pointer to the DCR data containing the DCR mapping
* for this controller instance.
* @mcopt1: The 32-bit Memory Controller Option 1 register value
* currently set for the controller, from which ECC capabilities
* and scrub mode are derived.
*
* This routine performs initialization of the EDAC memory controller
* instance and related driver-private data associated with the
* ibm,sdram-4xx-ddr2 memory controller the instance is bound to.
*
* Returns 0 if OK; otherwise, < 0 on error.
*/
static int ppc4xx_edac_mc_init(struct mem_ctl_info *mci,
struct platform_device *op,
const dcr_host_t *dcr_host, u32 mcopt1)
{
int status = 0;
const u32 memcheck = (mcopt1 & SDRAM_MCOPT1_MCHK_MASK);
struct ppc4xx_edac_pdata *pdata = NULL;
const struct device_node *np = op->dev.of_node;
if (of_match_device(ppc4xx_edac_match, &op->dev) == NULL)
return -EINVAL;
/* Initial driver pointers and private data */
mci->pdev = &op->dev;
dev_set_drvdata(mci->pdev, mci);
pdata = mci->pvt_info;
pdata->dcr_host = *dcr_host;
/* Initialize controller capabilities and configuration */
mci->mtype_cap = (MEM_FLAG_DDR | MEM_FLAG_RDDR |
MEM_FLAG_DDR2 | MEM_FLAG_RDDR2);
mci->edac_ctl_cap = (EDAC_FLAG_NONE |
EDAC_FLAG_EC |
EDAC_FLAG_SECDED);
mci->scrub_cap = SCRUB_NONE;
mci->scrub_mode = SCRUB_NONE;
/*
* Update the actual capabilites based on the MCOPT1[MCHK]
* settings. Scrubbing is only useful if reporting is enabled.
*/
switch (memcheck) {
case SDRAM_MCOPT1_MCHK_CHK:
mci->edac_cap = EDAC_FLAG_EC;
break;
case SDRAM_MCOPT1_MCHK_CHK_REP:
mci->edac_cap = (EDAC_FLAG_EC | EDAC_FLAG_SECDED);
mci->scrub_mode = SCRUB_SW_SRC;
break;
default:
mci->edac_cap = EDAC_FLAG_NONE;
break;
}
/* Initialize strings */
mci->mod_name = PPC4XX_EDAC_MODULE_NAME;
mci->ctl_name = ppc4xx_edac_match->compatible;
mci->dev_name = np->full_name;
/* Initialize callbacks */
mci->edac_check = ppc4xx_edac_check;
mci->ctl_page_to_phys = NULL;
/* Initialize chip select rows */
status = ppc4xx_edac_init_csrows(mci, mcopt1);
if (status)
ppc4xx_edac_mc_printk(KERN_ERR, mci,
"Failed to initialize rows!\n");
return status;
}
/**
* ppc4xx_edac_register_irq - setup and register controller interrupts
* @op: A pointer to the OpenFirmware device tree node associated
* with the controller this EDAC instance is bound to.
* @mci: A pointer to the EDAC memory controller instance
* associated with the ibm,sdram-4xx-ddr2 controller for which
* interrupts are being registered.
*
* This routine parses the correctable (CE) and uncorrectable error (UE)
* interrupts from the device tree node and maps and assigns them to
* the associated EDAC memory controller instance.
*
* Returns 0 if OK; otherwise, -ENODEV if the interrupts could not be
* mapped and assigned.
*/
static int ppc4xx_edac_register_irq(struct platform_device *op,
struct mem_ctl_info *mci)
{
int status = 0;
int ded_irq, sec_irq;
struct ppc4xx_edac_pdata *pdata = mci->pvt_info;
struct device_node *np = op->dev.of_node;
ded_irq = irq_of_parse_and_map(np, INTMAP_ECCDED_INDEX);
sec_irq = irq_of_parse_and_map(np, INTMAP_ECCSEC_INDEX);
if (!ded_irq || !sec_irq) {
ppc4xx_edac_mc_printk(KERN_ERR, mci,
"Unable to map interrupts.\n");
status = -ENODEV;
goto fail;
}
status = request_irq(ded_irq,
ppc4xx_edac_isr,
0,
"[EDAC] MC ECCDED",
mci);
if (status < 0) {
ppc4xx_edac_mc_printk(KERN_ERR, mci,
"Unable to request irq %d for ECC DED",
ded_irq);
status = -ENODEV;
goto fail1;
}
status = request_irq(sec_irq,
ppc4xx_edac_isr,
0,
"[EDAC] MC ECCSEC",
mci);
if (status < 0) {
ppc4xx_edac_mc_printk(KERN_ERR, mci,
"Unable to request irq %d for ECC SEC",
sec_irq);
status = -ENODEV;
goto fail2;
}
ppc4xx_edac_mc_printk(KERN_INFO, mci, "ECCDED irq is %d\n", ded_irq);
ppc4xx_edac_mc_printk(KERN_INFO, mci, "ECCSEC irq is %d\n", sec_irq);
pdata->irqs.ded = ded_irq;
pdata->irqs.sec = sec_irq;
return 0;
fail2:
free_irq(sec_irq, mci);
fail1:
free_irq(ded_irq, mci);
fail:
return status;
}
/**
* ppc4xx_edac_map_dcrs - locate and map controller registers
* @np: A pointer to the device tree node containing the DCR
* resources to map.
* @dcr_host: A pointer to the DCR data to populate with the
* DCR mapping.
*
* This routine attempts to locate in the device tree and map the DCR
* register resources associated with the controller's indirect DCR
* address and data windows.
*
* Returns 0 if the DCRs were successfully mapped; otherwise, < 0 on
* error.
*/
static int ppc4xx_edac_map_dcrs(const struct device_node *np,
dcr_host_t *dcr_host)
{
unsigned int dcr_base, dcr_len;
if (np == NULL || dcr_host == NULL)
return -EINVAL;
/* Get the DCR resource extent and sanity check the values. */
dcr_base = dcr_resource_start(np, 0);
dcr_len = dcr_resource_len(np, 0);
if (dcr_base == 0 || dcr_len == 0) {
ppc4xx_edac_printk(KERN_ERR,
"Failed to obtain DCR property.\n");
return -ENODEV;
}
if (dcr_len != SDRAM_DCR_RESOURCE_LEN) {
ppc4xx_edac_printk(KERN_ERR,
"Unexpected DCR length %d, expected %d.\n",
dcr_len, SDRAM_DCR_RESOURCE_LEN);
return -ENODEV;
}
/* Attempt to map the DCR extent. */
*dcr_host = dcr_map(np, dcr_base, dcr_len);
if (!DCR_MAP_OK(*dcr_host)) {
ppc4xx_edac_printk(KERN_INFO, "Failed to map DCRs.\n");
return -ENODEV;
}
return 0;
}
/**
* ppc4xx_edac_probe - check controller and bind driver
* @op: A pointer to the OpenFirmware device tree node associated
* with the controller being probed for driver binding.
*
* This routine probes a specific ibm,sdram-4xx-ddr2 controller
* instance for binding with the driver.
*
* Returns 0 if the controller instance was successfully bound to the
* driver; otherwise, < 0 on error.
*/
static int ppc4xx_edac_probe(struct platform_device *op)
{
int status = 0;
u32 mcopt1, memcheck;
dcr_host_t dcr_host;
const struct device_node *np = op->dev.of_node;
struct mem_ctl_info *mci = NULL;
struct edac_mc_layer layers[2];
static int ppc4xx_edac_instance;
/*
* At this point, we only support the controller realized on
* the AMCC PPC 405EX[r]. Reject anything else.
*/
if (!of_device_is_compatible(np, "ibm,sdram-405ex") &&
!of_device_is_compatible(np, "ibm,sdram-405exr")) {
ppc4xx_edac_printk(KERN_NOTICE,
"Only the PPC405EX[r] is supported.\n");
return -ENODEV;
}
/*
* Next, get the DCR property and attempt to map it so that we
* can probe the controller.
*/
status = ppc4xx_edac_map_dcrs(np, &dcr_host);
if (status)
return status;
/*
* First determine whether ECC is enabled at all. If not,
* there is no useful checking or monitoring that can be done
* for this controller.
*/
mcopt1 = mfsdram(&dcr_host, SDRAM_MCOPT1);
memcheck = (mcopt1 & SDRAM_MCOPT1_MCHK_MASK);
if (memcheck == SDRAM_MCOPT1_MCHK_NON) {
ppc4xx_edac_printk(KERN_INFO, "%pOF: No ECC memory detected or "
"ECC is disabled.\n", np);
status = -ENODEV;
goto done;
}
/*
* At this point, we know ECC is enabled, allocate an EDAC
* controller instance and perform the appropriate
* initialization.
*/
layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
layers[0].size = ppc4xx_edac_nr_csrows;
layers[0].is_virt_csrow = true;
layers[1].type = EDAC_MC_LAYER_CHANNEL;
layers[1].size = ppc4xx_edac_nr_chans;
layers[1].is_virt_csrow = false;
mci = edac_mc_alloc(ppc4xx_edac_instance, ARRAY_SIZE(layers), layers,
sizeof(struct ppc4xx_edac_pdata));
if (mci == NULL) {
ppc4xx_edac_printk(KERN_ERR, "%pOF: "
"Failed to allocate EDAC MC instance!\n",
np);
status = -ENOMEM;
goto done;
}
status = ppc4xx_edac_mc_init(mci, op, &dcr_host, mcopt1);
if (status) {
ppc4xx_edac_mc_printk(KERN_ERR, mci,
"Failed to initialize instance!\n");
goto fail;
}
/*
* We have a valid, initialized EDAC instance bound to the
* controller. Attempt to register it with the EDAC subsystem
* and, if necessary, register interrupts.
*/
if (edac_mc_add_mc(mci)) {
ppc4xx_edac_mc_printk(KERN_ERR, mci,
"Failed to add instance!\n");
status = -ENODEV;
goto fail;
}
if (edac_op_state == EDAC_OPSTATE_INT) {
status = ppc4xx_edac_register_irq(op, mci);
if (status)
goto fail1;
}
ppc4xx_edac_instance++;
return 0;
fail1:
edac_mc_del_mc(mci->pdev);
fail:
edac_mc_free(mci);
done:
return status;
}
/**
* ppc4xx_edac_remove - unbind driver from controller
* @op: A pointer to the OpenFirmware device tree node associated
* with the controller this EDAC instance is to be unbound/removed
* from.
*
* This routine unbinds the EDAC memory controller instance associated
* with the specified ibm,sdram-4xx-ddr2 controller described by the
* OpenFirmware device tree node passed as a parameter.
*
* Unconditionally returns 0.
*/
static int
ppc4xx_edac_remove(struct platform_device *op)
{
struct mem_ctl_info *mci = dev_get_drvdata(&op->dev);
struct ppc4xx_edac_pdata *pdata = mci->pvt_info;
if (edac_op_state == EDAC_OPSTATE_INT) {
free_irq(pdata->irqs.sec, mci);
free_irq(pdata->irqs.ded, mci);
}
dcr_unmap(pdata->dcr_host, SDRAM_DCR_RESOURCE_LEN);
edac_mc_del_mc(mci->pdev);
edac_mc_free(mci);
return 0;
}
/**
* ppc4xx_edac_opstate_init - initialize EDAC reporting method
*
* This routine ensures that the EDAC memory controller reporting
* method is mapped to a sane value as the EDAC core defines the value
* to EDAC_OPSTATE_INVAL by default. We don't call the global
* opstate_init as that defaults to polling and we want interrupt as
* the default.
*/
static inline void __init
ppc4xx_edac_opstate_init(void)
{
switch (edac_op_state) {
case EDAC_OPSTATE_POLL:
case EDAC_OPSTATE_INT:
break;
default:
edac_op_state = EDAC_OPSTATE_INT;
break;
}
ppc4xx_edac_printk(KERN_INFO, "Reporting type: %s\n",
((edac_op_state == EDAC_OPSTATE_POLL) ?
EDAC_OPSTATE_POLL_STR :
((edac_op_state == EDAC_OPSTATE_INT) ?
EDAC_OPSTATE_INT_STR :
EDAC_OPSTATE_UNKNOWN_STR)));
}
static struct platform_driver ppc4xx_edac_driver = {
.probe = ppc4xx_edac_probe,
.remove = ppc4xx_edac_remove,
.driver = {
.name = PPC4XX_EDAC_MODULE_NAME,
.of_match_table = ppc4xx_edac_match,
},
};
/**
* ppc4xx_edac_init - driver/module insertion entry point
*
* This routine is the driver/module insertion entry point. It
* initializes the EDAC memory controller reporting state and
* registers the driver as an OpenFirmware device tree platform
* driver.
*/
static int __init
ppc4xx_edac_init(void)
{
ppc4xx_edac_printk(KERN_INFO, PPC4XX_EDAC_MODULE_REVISION "\n");
ppc4xx_edac_opstate_init();
return platform_driver_register(&ppc4xx_edac_driver);
}
/**
* ppc4xx_edac_exit - driver/module removal entry point
*
* This routine is the driver/module removal entry point. It
* unregisters the driver as an OpenFirmware device tree platform
* driver.
*/
static void __exit
ppc4xx_edac_exit(void)
{
platform_driver_unregister(&ppc4xx_edac_driver);
}
module_init(ppc4xx_edac_init);
module_exit(ppc4xx_edac_exit);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Grant Erickson <gerickson@nuovations.com>");
MODULE_DESCRIPTION("EDAC MC Driver for the PPC4xx IBM DDR2 Memory Controller");
module_param(edac_op_state, int, 0444);
MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting State: "
"0=" EDAC_OPSTATE_POLL_STR ", 2=" EDAC_OPSTATE_INT_STR);