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author | Thomas Gleixner <tglx@linutronix.de> | 2019-06-23 15:23:58 +0200 |
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committer | Thomas Gleixner <tglx@linutronix.de> | 2019-06-28 00:57:21 +0200 |
commit | e37f0881e9d9ec8b12f242cc2b78d93259aa7f0f (patch) | |
tree | da0c60d587a7b7e7cc06232deac3d4b79448c13f /arch/x86/kernel/hpet.c | |
parent | 0b5c597de6aa30000480d6add2f37ef7de3f9312 (diff) | |
download | linux-stable-e37f0881e9d9ec8b12f242cc2b78d93259aa7f0f.tar.gz linux-stable-e37f0881e9d9ec8b12f242cc2b78d93259aa7f0f.tar.bz2 linux-stable-e37f0881e9d9ec8b12f242cc2b78d93259aa7f0f.zip |
x86/hpet: Introduce struct hpet_base and struct hpet_channel
Introduce new data structures to replace the ad hoc collection of separate
variables and pointers.
Replace the boot configuration store and restore as a first step.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Link: https://lkml.kernel.org/r/20190623132435.728456320@linutronix.de
Diffstat (limited to 'arch/x86/kernel/hpet.c')
-rw-r--r-- | arch/x86/kernel/hpet.c | 82 |
1 files changed, 48 insertions, 34 deletions
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index ed2d556f2c96..59a81d7fd05b 100644 --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -22,6 +22,17 @@ struct hpet_dev { char name[10]; }; +struct hpet_channel { + unsigned int num; + unsigned int boot_cfg; +}; + +struct hpet_base { + unsigned int nr_channels; + unsigned int boot_cfg; + struct hpet_channel *channels; +}; + #define HPET_MASK CLOCKSOURCE_MASK(32) #define HPET_DEV_USED_BIT 2 @@ -48,7 +59,7 @@ static struct irq_domain *hpet_domain; #endif static void __iomem *hpet_virt_address; -static u32 *hpet_boot_cfg; +static struct hpet_base hpet_base; static bool hpet_legacy_int_enabled; static unsigned long hpet_freq; @@ -860,6 +871,7 @@ int __init hpet_enable(void) { u32 hpet_period, cfg, id; unsigned int i, channels; + struct hpet_channel *hc; u64 freq; if (!is_hpet_capable()) @@ -899,34 +911,39 @@ int __init hpet_enable(void) /* This is the HPET channel number which is zero based */ channels = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT) + 1; -#ifdef CONFIG_HPET_EMULATE_RTC /* * The legacy routing mode needs at least two channels, tick timer * and the rtc emulation channel. */ - if (channels < 2) + if (IS_ENABLED(CONFIG_HPET_EMULATE_RTC) && channels < 2) goto out_nohpet; -#endif + hc = kcalloc(channels, sizeof(*hc), GFP_KERNEL); + if (!hc) { + pr_warn("Disabling HPET.\n"); + goto out_nohpet; + } + hpet_base.channels = hc; + hpet_base.nr_channels = channels; + + /* Read, store and sanitize the global configuration */ cfg = hpet_readl(HPET_CFG); - /* Allocate entries for the global and the channel configurations */ - hpet_boot_cfg = kmalloc_array(channels + 1, sizeof(*hpet_boot_cfg), - GFP_KERNEL); - if (hpet_boot_cfg) - *hpet_boot_cfg = cfg; - else - pr_warn("HPET initial state will not be saved\n"); + hpet_base.boot_cfg = cfg; cfg &= ~(HPET_CFG_ENABLE | HPET_CFG_LEGACY); hpet_writel(cfg, HPET_CFG); if (cfg) pr_warn("Global config: Unknown bits %#x\n", cfg); - for (i = 0; i < channels; ++i) { + /* Read, store and sanitize the per channel configuration */ + for (i = 0; i < channels; i++, hc++) { + hc->num = i; + cfg = hpet_readl(HPET_Tn_CFG(i)); - if (hpet_boot_cfg) - hpet_boot_cfg[i + 1] = cfg; + hc->boot_cfg = cfg; + cfg &= ~(HPET_TN_ENABLE | HPET_TN_LEVEL | HPET_TN_FSB); hpet_writel(cfg, HPET_Tn_CFG(i)); + cfg &= ~(HPET_TN_PERIODIC | HPET_TN_PERIODIC_CAP | HPET_TN_64BIT_CAP | HPET_TN_32BIT | HPET_TN_ROUTE | HPET_TN_FSB | HPET_TN_FSB_CAP); @@ -944,6 +961,9 @@ int __init hpet_enable(void) return 0; out_nohpet: + kfree(hpet_base.channels); + hpet_base.channels = NULL; + hpet_base.nr_channels = 0; hpet_clear_mapping(); hpet_address = 0; return 0; @@ -1000,30 +1020,24 @@ fs_initcall(hpet_late_init); void hpet_disable(void) { - if (is_hpet_capable() && hpet_virt_address) { - unsigned int cfg = hpet_readl(HPET_CFG), id, last; - - if (hpet_boot_cfg) - cfg = *hpet_boot_cfg; - else if (hpet_legacy_int_enabled) { - cfg &= ~HPET_CFG_LEGACY; - hpet_legacy_int_enabled = false; - } - cfg &= ~HPET_CFG_ENABLE; - hpet_writel(cfg, HPET_CFG); + unsigned int i; + u32 cfg; - if (!hpet_boot_cfg) - return; + if (!is_hpet_capable() || !hpet_virt_address) + return; - id = hpet_readl(HPET_ID); - last = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT); + /* Restore boot configuration with the enable bit cleared */ + cfg = hpet_base.boot_cfg; + cfg &= ~HPET_CFG_ENABLE; + hpet_writel(cfg, HPET_CFG); - for (id = 0; id <= last; ++id) - hpet_writel(hpet_boot_cfg[id + 1], HPET_Tn_CFG(id)); + /* Restore the channel boot configuration */ + for (i = 0; i < hpet_base.nr_channels; i++) + hpet_writel(hpet_base.channels[i].boot_cfg, HPET_Tn_CFG(i)); - if (*hpet_boot_cfg & HPET_CFG_ENABLE) - hpet_writel(*hpet_boot_cfg, HPET_CFG); - } + /* If the HPET was enabled at boot time, reenable it */ + if (hpet_base.boot_cfg & HPET_CFG_ENABLE) + hpet_writel(hpet_base.boot_cfg, HPET_CFG); } #ifdef CONFIG_HPET_EMULATE_RTC |