Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2002,2003 Broadcom Corporation
 */
 
/*
 * The Bus Watcher monitors internal bus transactions and maintains
 * counts of transactions with error status, logging details and
 * causing one of several interrupts.  This driver provides a handler
 * for those interrupts which aggregates the counts (to avoid
 * saturating the 8-bit counters) and provides a presence in
 * /proc/bus_watcher if PROC_FS is on.
 */
 
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <asm/io.h>
 
#include <asm/sibyte/sb1250.h>
#include <asm/sibyte/sb1250_regs.h>
#include <asm/sibyte/sb1250_int.h>
#include <asm/sibyte/sb1250_scd.h>
#if defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
#include <asm/sibyte/bcm1480_regs.h>
#endif
 
 
struct bw_stats_struct {
<------>uint64_t status;
<------>uint32_t l2_err;
<------>uint32_t memio_err;
<------>int status_printed;
<------>unsigned long l2_cor_d;
<------>unsigned long l2_bad_d;
<------>unsigned long l2_cor_t;
<------>unsigned long l2_bad_t;
<------>unsigned long mem_cor_d;
<------>unsigned long mem_bad_d;
<------>unsigned long bus_error;
} bw_stats;
 
 
static void print_summary(uint32_t status, uint32_t l2_err,
<------><------><------>  uint32_t memio_err)
{
<------>printk("Bus watcher error counters: %08x %08x\n", l2_err, memio_err);
<------>printk("\nLast recorded signature:\n");
<------>printk("Request %02x from %d, answered by %d with Dcode %d\n",
<------>       (unsigned int)(G_SCD_BERR_TID(status) & 0x3f),
<------>       (int)(G_SCD_BERR_TID(status) >> 6),
<------>       (int)G_SCD_BERR_RID(status),
<------>       (int)G_SCD_BERR_DCODE(status));
}
 
/*
 * check_bus_watcher is exported for use in situations where we want
 * to see the most recent status of the bus watcher, which might have
 * already been destructively read out of the registers.
 *
 * notes: this is currently used by the cache error handler
 *	  should provide locking against the interrupt handler
 */
void check_bus_watcher(void)
{
<------>u32 status, l2_err, memio_err;
 
#if defined(CONFIG_SIBYTE_BCM112X) || defined(CONFIG_SIBYTE_SB1250)
<------>/* Use non-destructive register */
<------>status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS_DEBUG));
#elif defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
<------>/* Use non-destructive register */
<------>/* Same as 1250 except BUS_ERR_STATUS_DEBUG is in a different place. */
<------>status = csr_in32(IOADDR(A_BCM1480_BUS_ERR_STATUS_DEBUG));
#else
#error bus watcher being built for unknown Sibyte SOC!
#endif
<------>if (!(status & 0x7fffffff)) {
<------><------>printk("Using last values reaped by bus watcher driver\n");
<------><------>status = bw_stats.status;
<------><------>l2_err = bw_stats.l2_err;
<------><------>memio_err = bw_stats.memio_err;
<------>} else {
<------><------>l2_err = csr_in32(IOADDR(A_BUS_L2_ERRORS));
<------><------>memio_err = csr_in32(IOADDR(A_BUS_MEM_IO_ERRORS));
<------>}
<------>if (status & ~(1UL << 31))
<------><------>print_summary(status, l2_err, memio_err);
<------>else
<------><------>printk("Bus watcher indicates no error\n");
}
 
#ifdef CONFIG_PROC_FS
 
/* For simplicity, I want to assume a single read is required each
   time */
static int bw_proc_show(struct seq_file *m, void *v)
{
<------>struct bw_stats_struct *stats = m->private;
 
<------>seq_puts(m, "SiByte Bus Watcher statistics\n");
<------>seq_puts(m, "-----------------------------\n");
<------>seq_printf(m, "L2-d-cor %8ld\nL2-d-bad %8ld\n",
<------><------>   stats->l2_cor_d, stats->l2_bad_d);
<------>seq_printf(m, "L2-t-cor %8ld\nL2-t-bad %8ld\n",
<------><------>   stats->l2_cor_t, stats->l2_bad_t);
<------>seq_printf(m, "MC-d-cor %8ld\nMC-d-bad %8ld\n",
<------><------>   stats->mem_cor_d, stats->mem_bad_d);
<------>seq_printf(m, "IO-err   %8ld\n", stats->bus_error);
<------>seq_puts(m, "\nLast recorded signature:\n");
<------>seq_printf(m, "Request %02x from %d, answered by %d with Dcode %d\n",
<------><------>   (unsigned int)(G_SCD_BERR_TID(stats->status) & 0x3f),
<------><------>   (int)(G_SCD_BERR_TID(stats->status) >> 6),
<------><------>   (int)G_SCD_BERR_RID(stats->status),
<------><------>   (int)G_SCD_BERR_DCODE(stats->status));
<------>/* XXXKW indicate multiple errors between printings, or stats
<------>   collection (or both)? */
<------>if (stats->status & M_SCD_BERR_MULTERRS)
<------><------>seq_puts(m, "Multiple errors observed since last check.\n");
<------>if (stats->status_printed) {
<------><------>seq_puts(m, "(no change since last printing)\n");
<------>} else {
<------><------>stats->status_printed = 1;
<------>}
 
<------>return 0;
}
 
static void create_proc_decoder(struct bw_stats_struct *stats)
{
<------>struct proc_dir_entry *ent;
 
<------>ent = proc_create_single_data("bus_watcher", S_IWUSR | S_IRUGO, NULL,
<------><------><------>bw_proc_show, stats);
<------>if (!ent) {
<------><------>printk(KERN_INFO "Unable to initialize bus_watcher /proc entry\n");
<------><------>return;
<------>}
}
 
#endif /* CONFIG_PROC_FS */
 
/*
 * sibyte_bw_int - handle bus watcher interrupts and accumulate counts
 *
 * notes: possible re-entry due to multiple sources
 *	  should check/indicate saturation
 */
static irqreturn_t sibyte_bw_int(int irq, void *data)
{
<------>struct bw_stats_struct *stats = data;
<------>unsigned long cntr;
#ifdef CONFIG_SIBYTE_BW_TRACE
<------>int i;
#endif
 
#ifdef CONFIG_SIBYTE_BW_TRACE
<------>csr_out32(M_SCD_TRACE_CFG_FREEZE, IOADDR(A_SCD_TRACE_CFG));
<------>csr_out32(M_SCD_TRACE_CFG_START_READ, IOADDR(A_SCD_TRACE_CFG));
 
<------>for (i=0; i<256*6; i++)
<------><------>printk("%016llx\n",
<------><------>       (long long)__raw_readq(IOADDR(A_SCD_TRACE_READ)));
 
<------>csr_out32(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG));
<------>csr_out32(M_SCD_TRACE_CFG_START, IOADDR(A_SCD_TRACE_CFG));
#endif
 
<------>/* Destructive read, clears register and interrupt */
<------>stats->status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS));
<------>stats->status_printed = 0;
 
<------>stats->l2_err = cntr = csr_in32(IOADDR(A_BUS_L2_ERRORS));
<------>stats->l2_cor_d += G_SCD_L2ECC_CORR_D(cntr);
<------>stats->l2_bad_d += G_SCD_L2ECC_BAD_D(cntr);
<------>stats->l2_cor_t += G_SCD_L2ECC_CORR_T(cntr);
<------>stats->l2_bad_t += G_SCD_L2ECC_BAD_T(cntr);
<------>csr_out32(0, IOADDR(A_BUS_L2_ERRORS));
 
<------>stats->memio_err = cntr = csr_in32(IOADDR(A_BUS_MEM_IO_ERRORS));
<------>stats->mem_cor_d += G_SCD_MEM_ECC_CORR(cntr);
<------>stats->mem_bad_d += G_SCD_MEM_ECC_BAD(cntr);
<------>stats->bus_error += G_SCD_MEM_BUSERR(cntr);
<------>csr_out32(0, IOADDR(A_BUS_MEM_IO_ERRORS));
 
<------>return IRQ_HANDLED;
}
 
int __init sibyte_bus_watcher(void)
{
<------>memset(&bw_stats, 0, sizeof(struct bw_stats_struct));
<------>bw_stats.status_printed = 1;
 
<------>if (request_irq(K_INT_BAD_ECC, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) {
<------><------>printk("Failed to register bus watcher BAD_ECC irq\n");
<------><------>return -1;
<------>}
<------>if (request_irq(K_INT_COR_ECC, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) {
<------><------>free_irq(K_INT_BAD_ECC, &bw_stats);
<------><------>printk("Failed to register bus watcher COR_ECC irq\n");
<------><------>return -1;
<------>}
<------>if (request_irq(K_INT_IO_BUS, sibyte_bw_int, 0, "Bus watcher", &bw_stats)) {
<------><------>free_irq(K_INT_BAD_ECC, &bw_stats);
<------><------>free_irq(K_INT_COR_ECC, &bw_stats);
<------><------>printk("Failed to register bus watcher IO_BUS irq\n");
<------><------>return -1;
<------>}
 
#ifdef CONFIG_PROC_FS
<------>create_proc_decoder(&bw_stats);
#endif
 
#ifdef CONFIG_SIBYTE_BW_TRACE
<------>csr_out32((M_SCD_TRSEQ_ASAMPLE | M_SCD_TRSEQ_DSAMPLE |
<------><------>   K_SCD_TRSEQ_TRIGGER_ALL),
<------><------>  IOADDR(A_SCD_TRACE_SEQUENCE_0));
<------>csr_out32(M_SCD_TRACE_CFG_RESET, IOADDR(A_SCD_TRACE_CFG));
<------>csr_out32(M_SCD_TRACE_CFG_START, IOADDR(A_SCD_TRACE_CFG));
#endif
 
<------>return 0;
}
 
device_initcall(sibyte_bus_watcher);