| Message ID | 26adc23c6e82d981c6a28470ec84f74443ee3221.1578886602.git.psampat@linux.ibm.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Introduce Self-Save API for deep stop states | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch powerpc/merge (20862247a368dbb75d6e97d82345999adaacf3cc) |
| snowpatch_ozlabs/build-ppc64le | warning | Build succeeded but added 2 new sparse warnings |
| snowpatch_ozlabs/build-ppc64be | warning | Build succeeded but added 2 new sparse warnings |
| snowpatch_ozlabs/build-ppc64e | success | Build succeeded |
| snowpatch_ozlabs/build-pmac32 | success | Build succeeded |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 116 lines checked |
| snowpatch_ozlabs/needsstable | success | Patch has no Fixes tags |
On Mon, Jan 13, 2020 at 09:15:09AM +0530, Pratik Rajesh Sampat wrote: > Parse the device tree for nodes self-save, self-restore and populate > support for the preferred SPRs based what was advertised by the device > tree. > > Signed-off-by: Pratik Rajesh Sampat <psampat@linux.ibm.com> > --- > arch/powerpc/platforms/powernv/idle.c | 104 ++++++++++++++++++++++++++ > 1 file changed, 104 insertions(+) > > diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c > index d67d4d0b169b..e910ff40b7e6 100644 > --- a/arch/powerpc/platforms/powernv/idle.c > +++ b/arch/powerpc/platforms/powernv/idle.c > @@ -1429,6 +1429,107 @@ static void __init pnv_probe_idle_states(void) > supported_cpuidle_states |= pnv_idle_states[i].flags; > } > > +/* > + * Extracts and populates the self save or restore capabilities > + * passed from the device tree node > + */ > +static int extract_save_restore_state_dt(struct device_node *np, int type) > +{ > + int nr_sprns = 0, i, bitmask_index; > + int rc = 0; > + u64 *temp_u64; > + const char *state_prop; > + u64 bit_pos; > + > + state_prop = of_get_property(np, "status", NULL); > + if (!state_prop) { > + pr_warn("opal: failed to find the active value for self save/restore node"); > + return -EINVAL; > + } > + if (strncmp(state_prop, "disabled", 8) == 0) { > + /* > + * if the feature is not active, strip the preferred_sprs from > + * that capability. > + */ > + if (type == SELF_RESTORE_TYPE) { > + for (i = 0; i < nr_preferred_sprs; i++) { > + preferred_sprs[i].supported_mode &= > + ~SELF_RESTORE_STRICT; > + } > + } else { > + for (i = 0; i < nr_preferred_sprs; i++) { > + preferred_sprs[i].supported_mode &= > + ~SELF_SAVE_STRICT; > + } > + } > + return 0; > + } > + nr_sprns = of_property_count_u64_elems(np, "sprn-bitmask"); > + if (nr_sprns <= 0) > + return rc; > + temp_u64 = kcalloc(nr_sprns, sizeof(u64), GFP_KERNEL); > + if (of_property_read_u64_array(np, "sprn-bitmask", > + temp_u64, nr_sprns)) { > + pr_warn("cpuidle-powernv: failed to find registers in DT\n"); > + kfree(temp_u64); > + return -EINVAL; > + } > + /* > + * Populate acknowledgment of support for the sprs in the global vector > + * gotten by the registers supplied by the firmware. > + * The registers are in a bitmask, bit index within > + * that specifies the SPR > + */ > + for (i = 0; i < nr_preferred_sprs; i++) { > + bitmask_index = preferred_sprs[i].spr / 64; > + bit_pos = preferred_sprs[i].spr % 64; > + if ((temp_u64[bitmask_index] & (1UL << bit_pos)) == 0) { > + if (type == SELF_RESTORE_TYPE) > + preferred_sprs[i].supported_mode &= > + ~SELF_RESTORE_STRICT; > + else > + preferred_sprs[i].supported_mode &= > + ~SELF_SAVE_STRICT; > + continue; > + } > + if (type == SELF_RESTORE_TYPE) { > + preferred_sprs[i].supported_mode |= > + SELF_RESTORE_STRICT; > + } else { > + preferred_sprs[i].supported_mode |= > + SELF_SAVE_STRICT; > + } > + } > + > + kfree(temp_u64); > + return rc; > +} > + > +static int pnv_parse_deepstate_dt(void) > +{ > + struct device_node *np, *np1; > + int rc = 0; > + > + /* Self restore register population */ > + np = of_find_node_by_path("/ibm,opal/power-mgt/self-restore"); > + if (!np) { > + pr_warn("opal: self restore Node not found"); > + } else { > + rc = extract_save_restore_state_dt(np, SELF_RESTORE_TYPE); > + if (rc != 0) > + return rc; > + } > + /* Self save register population */ > + np1 = of_find_node_by_path("/ibm,opal/power-mgt/self-save"); 'np' can be reused? 'np1' is not needed. Otherwise looks good. Reviewed-by: Ram Pai <linuxram@us.ibm.com> RP
diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c index d67d4d0b169b..e910ff40b7e6 100644 --- a/arch/powerpc/platforms/powernv/idle.c +++ b/arch/powerpc/platforms/powernv/idle.c @@ -1429,6 +1429,107 @@ static void __init pnv_probe_idle_states(void) supported_cpuidle_states |= pnv_idle_states[i].flags; } +/* + * Extracts and populates the self save or restore capabilities + * passed from the device tree node + */ +static int extract_save_restore_state_dt(struct device_node *np, int type) +{ + int nr_sprns = 0, i, bitmask_index; + int rc = 0; + u64 *temp_u64; + const char *state_prop; + u64 bit_pos; + + state_prop = of_get_property(np, "status", NULL); + if (!state_prop) { + pr_warn("opal: failed to find the active value for self save/restore node"); + return -EINVAL; + } + if (strncmp(state_prop, "disabled", 8) == 0) { + /* + * if the feature is not active, strip the preferred_sprs from + * that capability. + */ + if (type == SELF_RESTORE_TYPE) { + for (i = 0; i < nr_preferred_sprs; i++) { + preferred_sprs[i].supported_mode &= + ~SELF_RESTORE_STRICT; + } + } else { + for (i = 0; i < nr_preferred_sprs; i++) { + preferred_sprs[i].supported_mode &= + ~SELF_SAVE_STRICT; + } + } + return 0; + } + nr_sprns = of_property_count_u64_elems(np, "sprn-bitmask"); + if (nr_sprns <= 0) + return rc; + temp_u64 = kcalloc(nr_sprns, sizeof(u64), GFP_KERNEL); + if (of_property_read_u64_array(np, "sprn-bitmask", + temp_u64, nr_sprns)) { + pr_warn("cpuidle-powernv: failed to find registers in DT\n"); + kfree(temp_u64); + return -EINVAL; + } + /* + * Populate acknowledgment of support for the sprs in the global vector + * gotten by the registers supplied by the firmware. + * The registers are in a bitmask, bit index within + * that specifies the SPR + */ + for (i = 0; i < nr_preferred_sprs; i++) { + bitmask_index = preferred_sprs[i].spr / 64; + bit_pos = preferred_sprs[i].spr % 64; + if ((temp_u64[bitmask_index] & (1UL << bit_pos)) == 0) { + if (type == SELF_RESTORE_TYPE) + preferred_sprs[i].supported_mode &= + ~SELF_RESTORE_STRICT; + else + preferred_sprs[i].supported_mode &= + ~SELF_SAVE_STRICT; + continue; + } + if (type == SELF_RESTORE_TYPE) { + preferred_sprs[i].supported_mode |= + SELF_RESTORE_STRICT; + } else { + preferred_sprs[i].supported_mode |= + SELF_SAVE_STRICT; + } + } + + kfree(temp_u64); + return rc; +} + +static int pnv_parse_deepstate_dt(void) +{ + struct device_node *np, *np1; + int rc = 0; + + /* Self restore register population */ + np = of_find_node_by_path("/ibm,opal/power-mgt/self-restore"); + if (!np) { + pr_warn("opal: self restore Node not found"); + } else { + rc = extract_save_restore_state_dt(np, SELF_RESTORE_TYPE); + if (rc != 0) + return rc; + } + /* Self save register population */ + np1 = of_find_node_by_path("/ibm,opal/power-mgt/self-save"); + if (!np1) { + pr_warn("opal: self save Node not found"); + pr_warn("Legacy firmware. Assuming default self-restore support"); + } else { + rc = extract_save_restore_state_dt(np1, SELF_SAVE_TYPE); + } + return rc; +} + /* * This function parses device-tree and populates all the information * into pnv_idle_states structure. It also sets up nr_pnv_idle_states @@ -1577,6 +1678,9 @@ static int __init pnv_init_idle_states(void) return rc; pnv_probe_idle_states(); + rc = pnv_parse_deepstate_dt(); + if (rc) + return rc; if (!cpu_has_feature(CPU_FTR_ARCH_300)) { if (!(supported_cpuidle_states & OPAL_PM_SLEEP_ENABLED_ER1)) { power7_fastsleep_workaround_entry = false;
Parse the device tree for nodes self-save, self-restore and populate support for the preferred SPRs based what was advertised by the device tree. Signed-off-by: Pratik Rajesh Sampat <psampat@linux.ibm.com> --- arch/powerpc/platforms/powernv/idle.c | 104 ++++++++++++++++++++++++++ 1 file changed, 104 insertions(+)