^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * DAWR infrastructure
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright 2019, Michael Neuling, IBM Corporation.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/fs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/debugfs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <asm/debugfs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <asm/machdep.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <asm/hvcall.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) bool dawr_force_enable;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) EXPORT_SYMBOL_GPL(dawr_force_enable);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) int set_dawr(int nr, struct arch_hw_breakpoint *brk)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) unsigned long dawr, dawrx, mrd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) dawr = brk->address;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) dawrx = (brk->type & (HW_BRK_TYPE_READ | HW_BRK_TYPE_WRITE))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) << (63 - 58);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) dawrx |= ((brk->type & (HW_BRK_TYPE_TRANSLATE)) >> 2) << (63 - 59);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) dawrx |= (brk->type & (HW_BRK_TYPE_PRIV_ALL)) >> 3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * DAWR length is stored in field MDR bits 48:53. Matches range in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) * doublewords (64 bits) baised by -1 eg. 0b000000=1DW and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) * 0b111111=64DW.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) * brk->hw_len is in bytes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) * This aligns up to double word size, shifts and does the bias.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) mrd = ((brk->hw_len + 7) >> 3) - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) dawrx |= (mrd & 0x3f) << (63 - 53);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) if (ppc_md.set_dawr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) return ppc_md.set_dawr(nr, dawr, dawrx);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) if (nr == 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) mtspr(SPRN_DAWR0, dawr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) mtspr(SPRN_DAWRX0, dawrx);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) mtspr(SPRN_DAWR1, dawr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) mtspr(SPRN_DAWRX1, dawrx);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) static void disable_dawrs_cb(void *info)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) struct arch_hw_breakpoint null_brk = {0};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) for (i = 0; i < nr_wp_slots(); i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) set_dawr(i, &null_brk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) static ssize_t dawr_write_file_bool(struct file *file,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) const char __user *user_buf,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) size_t count, loff_t *ppos)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) struct arch_hw_breakpoint null_brk = {0};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) size_t rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) /* Send error to user if they hypervisor won't allow us to write DAWR */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) if (!dawr_force_enable &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) firmware_has_feature(FW_FEATURE_LPAR) &&
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) set_dawr(0, &null_brk) != H_SUCCESS)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) rc = debugfs_write_file_bool(file, user_buf, count, ppos);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) if (rc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) /* If we are clearing, make sure all CPUs have the DAWR cleared */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) if (!dawr_force_enable)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) smp_call_function(disable_dawrs_cb, NULL, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) static const struct file_operations dawr_enable_fops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) .read = debugfs_read_file_bool,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) .write = dawr_write_file_bool,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) .open = simple_open,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) .llseek = default_llseek,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) static int __init dawr_force_setup(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) if (cpu_has_feature(CPU_FTR_DAWR)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) /* Don't setup sysfs file for user control on P8 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) dawr_force_enable = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) if (PVR_VER(mfspr(SPRN_PVR)) == PVR_POWER9) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) /* Turn DAWR off by default, but allow admin to turn it on */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) debugfs_create_file_unsafe("dawr_enable_dangerous", 0600,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) powerpc_debugfs_root,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) &dawr_force_enable,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) &dawr_enable_fops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) arch_initcall(dawr_force_setup);
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
3 Commits
0 Branches
0 Tags