source: rtems/c/src/lib/libbsp/sparc/shared/amba/ahbstat.c @ a8595605

/*  AHB Status register driver
 *
 *  COPYRIGHT (c) 2009 - 2017.
 *  Cobham Gaisler AB.
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.rtems.org/license/LICENSE.
 */

#include <stdint.h>
#include <rtems.h>
#include <rtems/bspIo.h>
#include <drvmgr/drvmgr.h>
#include <drvmgr/ambapp_bus.h>

#include <bsp/ahbstat.h>

#define SPIN_IRQ_DECLARE(name)          RTEMS_INTERRUPT_LOCK_DECLARE(, name)
#define SPIN_IRQ_INIT(lock, name)       rtems_interrupt_lock_initialize(lock, name)
#define SPIN_IRQ_LOCK(lock, ctx)        rtems_interrupt_lock_acquire(lock, &(ctx))
#define SPIN_IRQ_UNLOCK(lock, ctx)      rtems_interrupt_lock_release(lock, &(ctx))
#define SPIN_IRQ_LOCK_ISR(lock, ctx)    rtems_interrupt_lock_acquire_isr(lock, &(ctx))
#define SPIN_IRQ_UNLOCK_ISR(lock, ctx)  rtems_interrupt_lock_release_isr(lock, &(ctx))
#define SPIN_IRQ_CTX                    rtems_interrupt_lock_context

#define REG_WRITE(addr, val) (*(volatile uint32_t *)(addr) = (uint32_t)(val))
#define REG_READ(addr) (*(volatile uint32_t *)(addr))

void ahbstat_isr(void *arg);

/* AHB fail interrupt callback to user. This function is declared weak so that
 * the user can define a function pointer variable containing the address
 * responsible for handling errors
 *
 * minor              Index of AHBSTAT hardware
 * regs               Register address of AHBSTAT
 * status             AHBSTAT status register at IRQ
 * failing_address    AHBSTAT Failing address register at IRQ
 *
 * * User return 
 *  0: print error onto terminal with printk and reenable AHBSTAT
 *  1: just re-enable AHBSTAT
 *  2: just print error
 *  3: do nothing, let user do custom handling
 */
int (*ahbstat_error)(
        int minor,
        struct ahbstat_regs *regs,
        uint32_t status,
        uint32_t failing_address
        ) __attribute__((weak)) = NULL;

#define AHBSTAT_STS_CE_BIT 9
#define AHBSTAT_STS_NE_BIT 8
#define AHBSTAT_STS_HW_BIT 7
#define AHBSTAT_STS_HM_BIT 3
#define AHBSTAT_STS_HS_BIT 0

#define AHBSTAT_STS_CE (1 << AHBSTAT_STS_CE_BIT)
#define AHBSTAT_STS_NE (1 << AHBSTAT_STS_NE_BIT)
#define AHBSTAT_STS_HW (1 << AHBSTAT_STS_HW_BIT)
#define AHBSTAT_STS_HM (0xf << AHBSTAT_STS_HM_BIT)
#define AHBSTAT_STS_HS (0x7 << AHBSTAT_STS_HS_BIT)

enum { DEVNAME_LEN = 9 };
struct ahbstat_priv {
        struct drvmgr_dev *dev;
        struct ahbstat_regs *regs;
        char devname[DEVNAME_LEN];
        int minor;
        /* Cached error */
        uint32_t last_status;
        uint32_t last_address;
        /* Spin-lock ISR protection */
        SPIN_IRQ_DECLARE(devlock);
};

static int ahbstat_init2(struct drvmgr_dev *dev);

struct drvmgr_drv_ops ahbstat_ops =
{
        .init = {NULL, ahbstat_init2, NULL, NULL},
        .remove = NULL,
        .info = NULL
};

struct amba_dev_id ahbstat_ids[] =
{
        {VENDOR_GAISLER, GAISLER_AHBSTAT},
        {0, 0}          /* Mark end of table */
};

struct amba_drv_info ahbstat_drv_info =
{
        {
                DRVMGR_OBJ_DRV,                 /* Driver */
                NULL,                           /* Next driver */
                NULL,                           /* Device list */
                DRIVER_AMBAPP_GAISLER_AHBSTAT_ID,/* Driver ID */
                "AHBSTAT_DRV",                  /* Driver Name */
                DRVMGR_BUS_TYPE_AMBAPP,         /* Bus Type */
                &ahbstat_ops,
                NULL,                           /* Funcs */
                0,                              /* No devices yet */
                sizeof(struct ahbstat_priv),
        },
        &ahbstat_ids[0]
};

void ahbstat_register_drv (void)
{
        drvmgr_drv_register(&ahbstat_drv_info.general);
}

static int ahbstat_init2(struct drvmgr_dev *dev)
{
        struct ahbstat_priv *priv;
        struct amba_dev_info *ambadev;

        priv = dev->priv;
        if (!priv)
                return DRVMGR_NOMEM;
        priv->dev = dev;

        /* Get device information from AMBA PnP information */
        ambadev = (struct amba_dev_info *)dev->businfo;
        if (ambadev == NULL)
                return DRVMGR_FAIL;
        priv->regs = (struct ahbstat_regs *)ambadev->info.apb_slv->start;
        priv->minor = dev->minor_drv;

        strncpy(&priv->devname[0], "ahbstat0", DEVNAME_LEN);
        priv->devname[7] += priv->minor;
        /*
         * Initialize spinlock for AHBSTAT Device. It is used to protect user
         * API calls involivng priv structure from updates in ISR.
         */
        SPIN_IRQ_INIT(&priv->devlock, priv->devname);

        /* Initialize hardware */
        REG_WRITE(&priv->regs->status, 0);

        /* Install IRQ handler */
        drvmgr_interrupt_register(dev, 0, priv->devname, ahbstat_isr, priv);

        return DRVMGR_OK;
}

void ahbstat_isr(void *arg)
{
        struct ahbstat_priv *priv = arg;
        uint32_t fadr, status;
        int rc;
        SPIN_IRQ_CTX lock_context;

        /* Get hardware status */
        status = REG_READ(&priv->regs->status);
        if ((status & AHBSTAT_STS_NE) == 0)
                return;

        /* IRQ generated by AHBSTAT core... handle it here */

        /* Get Failing address */
        fadr = REG_READ(&priv->regs->failing);

        SPIN_IRQ_LOCK_ISR(&priv->devlock, lock_context);
        priv->last_status = status;
        priv->last_address = fadr;
        SPIN_IRQ_UNLOCK_ISR(&priv->devlock, lock_context);

        /* Let user handle error, default to print the error and reenable HW
         *
         * User return 
         *  0: print error and reenable AHBSTAT
         *  1: just reenable AHBSTAT
         *  2: just print error
         *  3: do nothing
         */
        rc = 0;
        if (ahbstat_error != NULL)
                rc = ahbstat_error(priv->minor, priv->regs, status, fadr);

        if ((rc & 0x1) == 0) {
                printk("\n### AHBSTAT: %s %s error of size %ld by master %ld"
                        " at 0x%08lx\n",
                        status & AHBSTAT_STS_CE ? "single" : "non-correctable",
                        status & AHBSTAT_STS_HW ? "write" : "read",
                        (int) (status & AHBSTAT_STS_HS) >> AHBSTAT_STS_HS_BIT,
                        (int) (status & AHBSTAT_STS_HM) >> AHBSTAT_STS_HM_BIT,
                        fadr);
        }

        if ((rc & 0x2) == 0) {
                /* Trigger new interrupts */
                REG_WRITE(&priv->regs->status, 0);
        }
}

/* Get Last received AHB Error
 *
 * Return
 *   0: No error received
 *   1: Error Received, last status and address stored into argument pointers
 *  -1: No such AHBSTAT device
 */
int ahbstat_last_error(int minor, uint32_t *status, uint32_t *address)
{
        struct drvmgr_dev *dev;
        struct ahbstat_priv *priv;
        uint32_t last_status;
        uint32_t last_address;
        SPIN_IRQ_CTX lock_context;

        if (drvmgr_get_dev(&ahbstat_drv_info.general, minor, &dev)) {
                return -1;
        }
        priv = (struct ahbstat_priv *)dev->priv;

        /* Read information cached by ISR */
        SPIN_IRQ_LOCK(&priv->devlock, lock_context);
        last_status = REG_READ(&priv->last_status);
        last_address = REG_READ(&priv->last_address);
        SPIN_IRQ_UNLOCK(&priv->devlock, lock_context);

        *status = last_status;
        *address = last_address;

        return (last_status & AHBSTAT_STS_NE) >> AHBSTAT_STS_NE_BIT;
}

/* Get AHBSTAT registers address from minor. NULL returned if no such device */
struct ahbstat_regs *ahbstat_get_regs(int minor)
{
        struct drvmgr_dev *dev;
        struct ahbstat_priv *priv;

        if (drvmgr_get_dev(&ahbstat_drv_info.general, minor, &dev)) {
                return NULL;
        }
        priv = (struct ahbstat_priv *)dev->priv;

        return priv->regs;
}