// SPDX-License-Identifier: GPL-2.0-or-later
/*
* PowerNV setup code.
*
* Copyright 2011 IBM Corp.
*/
#undef DEBUG
#include <linux/cpu.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/tty.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/delay.h>
#include <linux/irq.h>
#include <linux/seq_buf.h>
#include <linux/seq_file.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/interrupt.h>
#include <linux/bug.h>
#include <linux/pci.h>
#include <linux/cpufreq.h>
#include <linux/memblock.h>
#include <asm/machdep.h>
#include <asm/firmware.h>
#include <asm/xics.h>
#include <asm/xive.h>
#include <asm/opal.h>
#include <asm/kexec.h>
#include <asm/smp.h>
#include <asm/tm.h>
#include <asm/setup.h>
#include <asm/security_features.h>
#include "powernv.h"
static bool __init fw_feature_is(const char *state, const char *name,
struct device_node *fw_features)
{
struct device_node *np;
bool rc = false;
np = of_get_child_by_name(fw_features, name);
if (np) {
rc = of_property_read_bool(np, state);
of_node_put(np);
}
return rc;
}
static void __init init_fw_feat_flags(struct device_node *np)
{
if (fw_feature_is("enabled", "inst-spec-barrier-ori31,31,0", np))
security_ftr_set(SEC_FTR_SPEC_BAR_ORI31);
if (fw_feature_is("enabled", "fw-bcctrl-serialized", np))
security_ftr_set(SEC_FTR_BCCTRL_SERIALISED);
if (fw_feature_is("enabled", "inst-l1d-flush-ori30,30,0", np))
security_ftr_set(SEC_FTR_L1D_FLUSH_ORI30);
if (fw_feature_is("enabled", "inst-l1d-flush-trig2", np))
security_ftr_set(SEC_FTR_L1D_FLUSH_TRIG2);
if (fw_feature_is("enabled", "fw-l1d-thread-split", np))
security_ftr_set(SEC_FTR_L1D_THREAD_PRIV);
if (fw_feature_is("enabled", "fw-count-cache-disabled", np))
security_ftr_set(SEC_FTR_COUNT_CACHE_DISABLED);
if (fw_feature_is("enabled", "fw-count-cache-flush-bcctr2,0,0", np))
security_ftr_set(SEC_FTR_BCCTR_FLUSH_ASSIST);
if (fw_feature_is("enabled", "needs-count-cache-flush-on-context-switch", np))
security_ftr_set(SEC_FTR_FLUSH_COUNT_CACHE);
/*
* The features below are enabled by default, so we instead look to see
* if firmware has *disabled* them, and clear them if so.
*/
if (fw_feature_is("disabled", "speculation-policy-favor-security", np))
security_ftr_clear(SEC_FTR_FAVOUR_SECURITY);
if (fw_feature_is("disabled", "needs-l1d-flush-msr-pr-0-to-1", np))
security_ftr_clear(SEC_FTR_L1D_FLUSH_PR);
if (fw_feature_is("disabled", "needs-l1d-flush-msr-hv-1-to-0", np))
security_ftr_clear(SEC_FTR_L1D_FLUSH_HV);
if (fw_feature_is("disabled", "needs-spec-barrier-for-bound-checks", np))
security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR);
if (fw_feature_is("enabled", "no-need-l1d-flush-msr-pr-1-to-0", np))
security_ftr_clear(SEC_FTR_L1D_FLUSH_ENTRY);
if (fw_feature_is("enabled", "no-need-l1d-flush-kernel-on-user-access", np))
security_ftr_clear(SEC_FTR_L1D_FLUSH_UACCESS);
if (fw_feature_is("enabled", "no-need-store-drain-on-priv-state-switch", np))
security_ftr_clear(SEC_FTR_STF_BARRIER);
}
static void __init pnv_setup_security_mitigations(void)
{
struct device_node *np, *fw_features;
enum l1d_flush_type type;
bool enable;
/* Default to fallback in case fw-features are not available */
type = L1D_FLUSH_FALLBACK;
np = of_find_node_by_name(NULL, "ibm,opal");
fw_features = of_get_child_by_name(np, "fw-features");
of_node_put(np);
if (fw_features) {
init_fw_feat_flags(fw_features);
of_node_put(fw_features);
if (security_ftr_enabled(SEC_FTR_L1D_FLUSH_TRIG2))
type = L1D_FLUSH_MTTRIG;
if (security_ftr_enabled(SEC_FTR_L1D_FLUSH_ORI30))
type = L1D_FLUSH_ORI;
}
/*
* The issues addressed by the entry and uaccess flush don't affect P7
* or P8, so on bare metal disable them explicitly in case firmware does
* not include the features to disable them. POWER9 and newer processors
* should have the appropriate firmware flags.
*/
if (pvr_version_is(PVR_POWER7) || pvr_version_is(PVR_POWER7p) ||
pvr_version_is(PVR_POWER8E) || pvr_version_is(PVR_POWER8NVL) ||
pvr_version_is(PVR_POWER8)) {
security_ftr_clear(SEC_FTR_L1D_FLUSH_ENTRY);
security_ftr_clear(SEC_FTR_L1D_FLUSH_UACCESS);
}
enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && \
(security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR) || \
security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV));
setup_rfi_flush(type, enable);
setup_count_cache_flush();
enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
security_ftr_enabled(SEC_FTR_L1D_FLUSH_ENTRY);
setup_entry_flush(enable);
enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
security_ftr_enabled(SEC_FTR_L1D_FLUSH_UACCESS);
setup_uaccess_flush(enable);
setup_stf_barrier();
}
static void __init pnv_check_guarded_cores(void)
{
struct device_node *dn;
int bad_count = 0;
for_each_node_by_type(dn, "cpu") {
if (of_property_match_string(dn, "status", "bad") >= 0)
bad_count++;
}
if (bad_count) {
printk(" _ _______________\n");
pr_cont(" | | / \\\n");
pr_cont(" | | | WARNING! |\n");
pr_cont(" | | | |\n");
pr_cont(" | | | It looks like |\n");
pr_cont(" |_| | you have %*d |\n", 3, bad_count);
pr_cont(" _ | guarded cores |\n");
pr_cont(" (_) \\_______________/\n");
}
}
static void __init pnv_setup_arch(void)
{
set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT);
pnv_setup_security_mitigations();
/* Initialize SMP */
pnv_smp_init();
/* Setup RTC and NVRAM callbacks */
if (firmware_has_feature(FW_FEATURE_OPAL))
opal_nvram_init();
/* Enable NAP mode */
powersave_nap = 1;
pnv_check_guarded_cores();
/* XXX PMCS */
pnv_rng_init();
}
static void __init pnv_add_hw_description(void)
{
struct device_node *dn;
const char *s;
dn = of_find_node_by_path("/ibm,opal/firmware");
if (!dn)
return;
if (of_property_read_string(dn, "version", &s) == 0 ||
of_property_read_string(dn, "git-id", &s) == 0)
seq_buf_printf(&ppc_hw_desc, "opal:%s ", s);
if (of_property_read_string(dn, "mi-version", &s) == 0)
seq_buf_printf(&ppc_hw_desc, "mi:%s ", s);
of_node_put(dn);
}
static void __init pnv_init(void)
{
pnv_add_hw_description();
/*
* Initialize the LPC bus now so that legacy serial
* ports can be found on it
*/
opal_lpc_init();
#ifdef CONFIG_HVC_OPAL
if (firmware_has_feature(FW_FEATURE_OPAL))
hvc_opal_init_early();
else
#endif
add_preferred_console("hvc", 0, NULL);
#ifdef CONFIG_PPC_64S_HASH_MMU
if (!radix_enabled()) {
size_t size = sizeof(struct slb_entry) * mmu_slb_size;
int i;
/* Allocate per cpu area to save old slb contents during MCE */
for_each_possible_cpu(i) {
paca_ptrs[i]->mce_faulty_slbs =
memblock_alloc_node(size,
__alignof__(struct slb_entry),
cpu_to_node(i));
}
}
#endif
}
static void __init pnv_init_IRQ(void)
{
/* Try using a XIVE if available, otherwise use a XICS */
if (!xive_native_init())
xics_init();
WARN_ON(!ppc_md.get_irq);
}
static void pnv_show_cpuinfo(struct seq_file *m)
{
struct device_node *root;
const char *model = "";
root = of_find_node_by_path("/");
if (root)
model = of_get_property(root, "model", NULL);
seq_printf(m, "machine\t\t: PowerNV %s\n", model);
if (firmware_has_feature(FW_FEATURE_OPAL))
seq_printf(m, "firmware\t: OPAL\n");
else
seq_printf(m, "firmware\t: BML\n");
of_node_put(root);
if (radix_enabled())
seq_printf(m, "MMU\t\t: Radix\n");
else
seq_printf(m, "MMU\t\t: Hash\n");
}
static void pnv_prepare_going_down(void)
{
/*
* Disable all notifiers from OPAL, we can't
* service interrupts anymore anyway
*/
opal_event_shutdown();
/* Print flash update message if one is scheduled. */
opal_flash_update_print_message();
smp_send_stop();
hard_irq_disable();
}
static void __noreturn pnv_restart(char *cmd)
{
long rc;
pnv_prepare_going_down();
do {
if (!cmd || !strlen(cmd))
rc = opal_cec_reboot();
else if (strcmp(cmd, "full") == 0)
rc = opal_cec_reboot2(OPAL_REBOOT_FULL_IPL, NULL);
else if (strcmp(cmd, "mpipl") == 0)
rc = opal_cec_reboot2(OPAL_REBOOT_MPIPL, NULL);
else if (strcmp(cmd, "error") == 0)
rc = opal_cec_reboot2(OPAL_REBOOT_PLATFORM_ERROR, NULL);
else if (strcmp(cmd, "fast") == 0)
rc = opal_cec_reboot2(OPAL_REBOOT_FAST, NULL);
else
rc = OPAL_UNSUPPORTED;
if (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
/* Opal is busy wait for some time and retry */
opal_poll_events(NULL);
mdelay(10);
} else if (cmd && rc) {
/* Unknown error while issuing reboot */
if (rc == OPAL_UNSUPPORTED)
pr_err("Unsupported '%s' reboot.\n", cmd);
else
pr_err("Unable to issue '%s' reboot. Err=%ld\n",
cmd, rc);
pr_info("Forcing a cec-reboot\n");
cmd = NULL;
rc = OPAL_BUSY;
} else if (rc != OPAL_SUCCESS) {
/* Unknown error while issuing cec-reboot */
pr_err("Unable to reboot. Err=%ld\n", rc);
}
} while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT);
for (;;)
opal_poll_events(NULL);
}
static void __noreturn pnv_power_off(void)
{
long rc = OPAL_BUSY;
pnv_prepare_going_down();
while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
rc = opal_cec_power_down(0);
if (rc == OPAL_BUSY_EVENT)
opal_poll_events(NULL);
else
mdelay(10);
}
for (;;)
opal_poll_events(NULL);
}
static void __noreturn pnv_halt(void)
{
pnv_power_off();
}
static void pnv_progress(char *s, unsigned short hex)
{
}
static void pnv_shutdown(void)
{
/* Let the PCI code clear up IODA tables */
pnv_pci_shutdown();
/*
* Stop OPAL activity: Unregister all OPAL interrupts so they
* don't fire up while we kexec and make sure all potentially
* DMA'ing ops are complete (such as dump retrieval).
*/
opal_shutdown();
}
#ifdef CONFIG_KEXEC_CORE
static void pnv_kexec_wait_secondaries_down(void)
{
int my_cpu, i, notified = -1;
my_cpu = get_cpu();
for_each_online_cpu(i) {
uint8_t status;
int64_t rc, timeout = 1000;
if (i == my_cpu)
continue;
for (;;) {
rc = opal_query_cpu_status(get_hard_smp_processor_id(i),
&status);
if (rc != OPAL_SUCCESS || status != OPAL_THREAD_STARTED)
break;
barrier();
if (i != notified) {
printk(KERN_INFO "kexec: waiting for cpu %d "
"(physical %d) to enter OPAL\n",
i, paca_ptrs[i]->hw_cpu_id);
notified = i;
}
/*
* On crash secondaries might be unreachable or hung,
* so timeout if we've waited too long
* */
mdelay(1);
if (timeout-- == 0) {
printk(KERN_ERR "kexec: timed out waiting for "
"cpu %d (physical %d) to enter OPAL\n",
i, paca_ptrs[i]->hw_cpu_id);
break;
}
}
}
}
static void pnv_kexec_cpu_down(int crash_shutdown, int secondary)
{
u64 reinit_flags;
if (xive_enabled())
xive_teardown_cpu();
else
xics_kexec_teardown_cpu(secondary);
/* On OPAL, we return all CPUs to firmware */
if (!firmware_has_feature(FW_FEATURE_OPAL))
return;
if (secondary) {
/* Return secondary CPUs to firmware on OPAL v3 */
mb();
get_paca()->kexec_state = KEXEC_STATE_REAL_MODE;
mb();
/* Return the CPU to OPAL */
opal_return_cpu();
} else {
/* Primary waits for the secondaries to have reached OPAL */
pnv_kexec_wait_secondaries_down();
/* Switch XIVE back to emulation mode */
if (xive_enabled())
xive_shutdown();
/*
* We might be running as little-endian - now that interrupts
* are disabled, reset the HILE bit to big-endian so we don't
* take interrupts in the wrong endian later
*
* We reinit to enable both radix and hash on P9 to ensure
* the mode used by the next kernel is always supported.
*/
reinit_flags = OPAL_REINIT_CPUS_HILE_BE;
if (cpu_has_feature(CPU_FTR_ARCH_300))
reinit_flags |= OPAL_REINIT_CPUS_MMU_RADIX |
OPAL_REINIT_CPUS_MMU_HASH;
opal_reinit_cpus(reinit_flags);
}
}
#endif /* CONFIG_KEXEC_CORE */
#ifdef CONFIG_MEMORY_HOTPLUG
static unsigned long pnv_memory_block_size(void)
{
return memory_block_size;
}
#endif
static void __init pnv_setup_machdep_opal(void)
{
ppc_md.get_boot_time = opal_get_boot_time;
ppc_md.restart = pnv_restart;
pm_power_off = pnv_power_off;
ppc_md.halt = pnv_halt;
/* ppc_md.system_reset_exception gets filled in by pnv_smp_init() */
ppc_md.machine_check_exception = opal_machine_check;
ppc_md.mce_check_early_recovery = opal_mce_check_early_recovery;
if (opal_check_token(OPAL_HANDLE_HMI2))
ppc_md.hmi_exception_early = opal_hmi_exception_early2;
else
ppc_md.hmi_exception_early = opal_hmi_exception_early;
ppc_md.handle_hmi_exception = opal_handle_hmi_exception;
}
static int __init pnv_probe(void)
{
if (firmware_has_feature(FW_FEATURE_OPAL))
pnv_setup_machdep_opal();
pr_debug("PowerNV detected !\n");
pnv_init();
return 1;
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
void __init pnv_tm_init(void)
{
if (!firmware_has_feature(FW_FEATURE_OPAL) ||
!pvr_version_is(PVR_POWER9) ||
early_cpu_has_feature(CPU_FTR_TM))
return;
if (opal_reinit_cpus(OPAL_REINIT_CPUS_TM_SUSPEND_DISABLED) != OPAL_SUCCESS)
return;
pr_info("Enabling TM (Transactional Memory) with Suspend Disabled\n");
cur_cpu_spec->cpu_features |= CPU_FTR_TM;
/* Make sure "normal" HTM is off (it should be) */
cur_cpu_spec->cpu_user_features2 &= ~PPC_FEATURE2_HTM;
/* Turn on no suspend mode, and HTM no SC */
cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NO_SUSPEND | \
PPC_FEATURE2_HTM_NOSC;
tm_suspend_disabled = true;
}
#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
/*
* Returns the cpu frequency for 'cpu' in Hz. This is used by
* /proc/cpuinfo
*/
static unsigned long pnv_get_proc_freq(unsigned int cpu)
{
unsigned long ret_freq;
ret_freq = cpufreq_get(cpu) * 1000ul;
/*
* If the backend cpufreq driver does not exist,
* then fallback to old way of reporting the clockrate.
*/
if (!ret_freq)
ret_freq = ppc_proc_freq;
return ret_freq;
}
static long pnv_machine_check_early(struct pt_regs *regs)
{
long handled = 0;
if (cur_cpu_spec && cur_cpu_spec->machine_check_early)
handled = cur_cpu_spec->machine_check_early(regs);
return handled;
}
define_machine(powernv) {
.name = "PowerNV",
.compatible = "ibm,powernv",
.probe = pnv_probe,
.setup_arch = pnv_setup_arch,
.init_IRQ = pnv_init_IRQ,
.show_cpuinfo = pnv_show_cpuinfo,
.get_proc_freq = pnv_get_proc_freq,
.discover_phbs = pnv_pci_init,
.progress = pnv_progress,
.machine_shutdown = pnv_shutdown,
.power_save = NULL,
.machine_check_early = pnv_machine_check_early,
#ifdef CONFIG_KEXEC_CORE
.kexec_cpu_down = pnv_kexec_cpu_down,
#endif
#ifdef CONFIG_MEMORY_HOTPLUG
.memory_block_size = pnv_memory_block_size,
#endif
};
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