diff options
| -rw-r--r-- | arch/x86/Kconfig | 8 | ||||
| -rw-r--r-- | arch/x86/include/asm/iosf_mbi.h | 90 | ||||
| -rw-r--r-- | arch/x86/include/asm/tsc.h | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/Makefile | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/iosf_mbi.c | 226 | ||||
| -rw-r--r-- | arch/x86/kernel/tsc.c | 10 | ||||
| -rw-r--r-- | arch/x86/kernel/tsc_msr.c | 127 |
7 files changed, 466 insertions, 1 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 6a990e2107f5..5216e283820d 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2358,6 +2358,14 @@ config X86_DMA_REMAP bool depends on STA2X11 +config IOSF_MBI + bool + depends on PCI + ---help--- + To be selected by modules requiring access to the Intel OnChip System + Fabric (IOSF) Sideband MailBox Interface (MBI). For MBI platforms + enumerable by PCI. + source "net/Kconfig" source "drivers/Kconfig" diff --git a/arch/x86/include/asm/iosf_mbi.h b/arch/x86/include/asm/iosf_mbi.h new file mode 100644 index 000000000000..8e71c7941767 --- /dev/null +++ b/arch/x86/include/asm/iosf_mbi.h @@ -0,0 +1,90 @@ +/* + * iosf_mbi.h: Intel OnChip System Fabric MailBox access support + */ + +#ifndef IOSF_MBI_SYMS_H +#define IOSF_MBI_SYMS_H + +#define MBI_MCR_OFFSET 0xD0 +#define MBI_MDR_OFFSET 0xD4 +#define MBI_MCRX_OFFSET 0xD8 + +#define MBI_RD_MASK 0xFEFFFFFF +#define MBI_WR_MASK 0X01000000 + +#define MBI_MASK_HI 0xFFFFFF00 +#define MBI_MASK_LO 0x000000FF +#define MBI_ENABLE 0xF0 + +/* Baytrail available units */ +#define BT_MBI_UNIT_AUNIT 0x00 +#define BT_MBI_UNIT_SMC 0x01 +#define BT_MBI_UNIT_CPU 0x02 +#define BT_MBI_UNIT_BUNIT 0x03 +#define BT_MBI_UNIT_PMC 0x04 +#define BT_MBI_UNIT_GFX 0x06 +#define BT_MBI_UNIT_SMI 0x0C +#define BT_MBI_UNIT_USB 0x43 +#define BT_MBI_UNIT_SATA 0xA3 +#define BT_MBI_UNIT_PCIE 0xA6 + +/* Baytrail read/write opcodes */ +#define BT_MBI_AUNIT_READ 0x10 +#define BT_MBI_AUNIT_WRITE 0x11 +#define BT_MBI_SMC_READ 0x10 +#define BT_MBI_SMC_WRITE 0x11 +#define BT_MBI_CPU_READ 0x10 +#define BT_MBI_CPU_WRITE 0x11 +#define BT_MBI_BUNIT_READ 0x10 +#define BT_MBI_BUNIT_WRITE 0x11 +#define BT_MBI_PMC_READ 0x06 +#define BT_MBI_PMC_WRITE 0x07 +#define BT_MBI_GFX_READ 0x00 +#define BT_MBI_GFX_WRITE 0x01 +#define BT_MBI_SMIO_READ 0x06 +#define BT_MBI_SMIO_WRITE 0x07 +#define BT_MBI_USB_READ 0x06 +#define BT_MBI_USB_WRITE 0x07 +#define BT_MBI_SATA_READ 0x00 +#define BT_MBI_SATA_WRITE 0x01 +#define BT_MBI_PCIE_READ 0x00 +#define BT_MBI_PCIE_WRITE 0x01 + +/** + * iosf_mbi_read() - MailBox Interface read command + * @port: port indicating subunit being accessed + * @opcode: port specific read or write opcode + * @offset: register address offset + * @mdr: register data to be read + * + * Locking is handled by spinlock - cannot sleep. + * Return: Nonzero on error + */ +int iosf_mbi_read(u8 port, u8 opcode, u32 offset, u32 *mdr); + +/** + * iosf_mbi_write() - MailBox unmasked write command + * @port: port indicating subunit being accessed + * @opcode: port specific read or write opcode + * @offset: register address offset + * @mdr: register data to be written + * + * Locking is handled by spinlock - cannot sleep. + * Return: Nonzero on error + */ +int iosf_mbi_write(u8 port, u8 opcode, u32 offset, u32 mdr); + +/** + * iosf_mbi_modify() - MailBox masked write command + * @port: port indicating subunit being accessed + * @opcode: port specific read or write opcode + * @offset: register address offset + * @mdr: register data being modified + * @mask: mask indicating bits in mdr to be modified + * + * Locking is handled by spinlock - cannot sleep. + * Return: Nonzero on error + */ +int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask); + +#endif /* IOSF_MBI_SYMS_H */ diff --git a/arch/x86/include/asm/tsc.h b/arch/x86/include/asm/tsc.h index 235be70d5bb4..57ae63cd6ee2 100644 --- a/arch/x86/include/asm/tsc.h +++ b/arch/x86/include/asm/tsc.h @@ -65,4 +65,7 @@ extern int notsc_setup(char *); extern void tsc_save_sched_clock_state(void); extern void tsc_restore_sched_clock_state(void); +/* MSR based TSC calibration for Intel Atom SoC platforms */ +int try_msr_calibrate_tsc(unsigned long *fast_calibrate); + #endif /* _ASM_X86_TSC_H */ diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 4b7b9273100a..cb648c84b327 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -33,7 +33,7 @@ obj-$(CONFIG_SYSFS) += ksysfs.o obj-y += bootflag.o e820.o obj-y += pci-dma.o quirks.o topology.o kdebugfs.o obj-y += alternative.o i8253.o pci-nommu.o hw_breakpoint.o -obj-y += tsc.o io_delay.o rtc.o +obj-y += tsc.o tsc_msr.o io_delay.o rtc.o obj-y += pci-iommu_table.o obj-y += resource.o @@ -103,6 +103,7 @@ obj-$(CONFIG_EFI) += sysfb_efi.o obj-$(CONFIG_PERF_EVENTS) += perf_regs.o obj-$(CONFIG_TRACING) += tracepoint.o +obj-$(CONFIG_IOSF_MBI) += iosf_mbi.o ### # 64 bit specific files diff --git a/arch/x86/kernel/iosf_mbi.c b/arch/x86/kernel/iosf_mbi.c new file mode 100644 index 000000000000..c3aae6672843 --- /dev/null +++ b/arch/x86/kernel/iosf_mbi.c @@ -0,0 +1,226 @@ +/* + * IOSF-SB MailBox Interface Driver + * Copyright (c) 2013, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * + * The IOSF-SB is a fabric bus available on Atom based SOC's that uses a + * mailbox interface (MBI) to communicate with mutiple devices. This + * driver implements access to this interface for those platforms that can + * enumerate the device using PCI. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/pci.h> + +#include <asm/iosf_mbi.h> + +static DEFINE_SPINLOCK(iosf_mbi_lock); + +static inline u32 iosf_mbi_form_mcr(u8 op, u8 port, u8 offset) +{ + return (op << 24) | (port << 16) | (offset << 8) | MBI_ENABLE; +} + +static struct pci_dev *mbi_pdev; /* one mbi device */ + +static int iosf_mbi_pci_read_mdr(u32 mcrx, u32 mcr, u32 *mdr) +{ + int result; + + if (!mbi_pdev) + return -ENODEV; + + if (mcrx) { + result = pci_write_config_dword(mbi_pdev, MBI_MCRX_OFFSET, + mcrx); + if (result < 0) + goto fail_read; + } + + result = pci_write_config_dword(mbi_pdev, MBI_MCR_OFFSET, mcr); + if (result < 0) + goto fail_read; + + result = pci_read_config_dword(mbi_pdev, MBI_MDR_OFFSET, mdr); + if (result < 0) + goto fail_read; + + return 0; + +fail_read: + dev_err(&mbi_pdev->dev, "PCI config access failed with %d\n", result); + return result; +} + +static int iosf_mbi_pci_write_mdr(u32 mcrx, u32 mcr, u32 mdr) +{ + int result; + + if (!mbi_pdev) + return -ENODEV; + + result = pci_write_config_dword(mbi_pdev, MBI_MDR_OFFSET, mdr); + if (result < 0) + goto fail_write; + + if (mcrx) { + result = pci_write_config_dword(mbi_pdev, MBI_MCRX_OFFSET, + mcrx); + if (result < 0) + goto fail_write; + } + + result = pci_write_config_dword(mbi_pdev, MBI_MCR_OFFSET, mcr); + if (result < 0) + goto fail_write; + + return 0; + +fail_write: + dev_err(&mbi_pdev->dev, "PCI config access failed with %d\n", result); + return result; +} + +int iosf_mbi_read(u8 port, u8 opcode, u32 offset, u32 *mdr) +{ + u32 mcr, mcrx; + unsigned long flags; + int ret; + + /*Access to the GFX unit is handled by GPU code */ + if (port == BT_MBI_UNIT_GFX) { + WARN_ON(1); + return -EPERM; + } + + mcr = iosf_mbi_form_mcr(opcode, port, offset & MBI_MASK_LO); + mcrx = offset & MBI_MASK_HI; + + spin_lock_irqsave(&iosf_mbi_lock, flags); + ret = iosf_mbi_pci_read_mdr(mcrx, mcr, mdr); + spin_unlock_irqrestore(&iosf_mbi_lock, flags); + + return ret; +} +EXPORT_SYMBOL(iosf_mbi_read); + +int iosf_mbi_write(u8 port, u8 opcode, u32 offset, u32 mdr) +{ + u32 mcr, mcrx; + unsigned long flags; + int ret; + + /*Access to the GFX unit is handled by GPU code */ + if (port == BT_MBI_UNIT_GFX) { + WARN_ON(1); + return -EPERM; + } + + mcr = iosf_mbi_form_mcr(opcode, port, offset & MBI_MASK_LO); + mcrx = offset & MBI_MASK_HI; + + spin_lock_irqsave(&iosf_mbi_lock, flags); + ret = iosf_mbi_pci_write_mdr(mcrx, mcr, mdr); + spin_unlock_irqrestore(&iosf_mbi_lock, flags); + + return ret; +} +EXPORT_SYMBOL(iosf_mbi_write); + +int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask) +{ + u32 mcr, mcrx; + u32 value; + unsigned long flags; + int ret; + + /*Access to the GFX unit is handled by GPU code */ + if (port == BT_MBI_UNIT_GFX) { + WARN_ON(1); + return -EPERM; + } + + mcr = iosf_mbi_form_mcr(opcode, port, offset & MBI_MASK_LO); + mcrx = offset & MBI_MASK_HI; + + spin_lock_irqsave(&iosf_mbi_lock, flags); + + /* Read current mdr value */ + ret = iosf_mbi_pci_read_mdr(mcrx, mcr & MBI_RD_MASK, &value); + if (ret < 0) { + spin_unlock_irqrestore(&iosf_mbi_lock, flags); + return ret; + } + + /* Apply mask */ + value &= ~mask; + mdr &= mask; + value |= mdr; + + /* Write back */ + ret = iosf_mbi_pci_write_mdr(mcrx, mcr | MBI_WR_MASK, value); + + spin_unlock_irqrestore(&iosf_mbi_lock, flags); + + return ret; +} +EXPORT_SYMBOL(iosf_mbi_modify); + +static int iosf_mbi_probe(struct pci_dev *pdev, + const struct pci_device_id *unused) +{ + int ret; + + ret = pci_enable_device(pdev); + if (ret < 0) { + dev_err(&pdev->dev, "error: could not enable device\n"); + return ret; + } + + mbi_pdev = pci_dev_get(pdev); + return 0; +} + +static DEFINE_PCI_DEVICE_TABLE(iosf_mbi_pci_ids) = { + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0F00) }, + { 0, }, +}; +MODULE_DEVICE_TABLE(pci, iosf_mbi_pci_ids); + +static struct pci_driver iosf_mbi_pci_driver = { + .name = "iosf_mbi_pci", + .probe = iosf_mbi_probe, + .id_table = iosf_mbi_pci_ids, +}; + +static int __init iosf_mbi_init(void) +{ + return pci_register_driver(&iosf_mbi_pci_driver); +} + +static void __exit iosf_mbi_exit(void) +{ + pci_unregister_driver(&iosf_mbi_pci_driver); + if (mbi_pdev) { + pci_dev_put(mbi_pdev); + mbi_pdev = NULL; + } +} + +module_init(iosf_mbi_init); +module_exit(iosf_mbi_exit); + +MODULE_AUTHOR("David E. Box <david.e.box@linux.intel.com>"); +MODULE_DESCRIPTION("IOSF Mailbox Interface accessor"); +MODULE_LICENSE("GPL v2"); diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index 6377fb28b958..a3acbac2ee72 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -651,6 +651,16 @@ unsigned long native_calibrate_tsc(void) unsigned long flags, latch, ms, fast_calibrate; int hpet = is_hpet_enabled(), i, loopmin; + /* Calibrate TSC using MSR for Intel Atom SoCs */ + local_irq_save(flags); + i = try_msr_calibrate_tsc(&fast_calibrate); + local_irq_restore(flags); + if (i >= 0) { + if (i == 0) + pr_warn("Fast TSC calibration using MSR failed\n"); + return fast_calibrate; + } + local_irq_save(flags); fast_calibrate = quick_pit_calibrate(); local_irq_restore(flags); diff --git a/arch/x86/kernel/tsc_msr.c b/arch/x86/kernel/tsc_msr.c new file mode 100644 index 000000000000..8b5434f4389f --- /dev/null +++ b/arch/x86/kernel/tsc_msr.c @@ -0,0 +1,127 @@ +/* + * tsc_msr.c - MSR based TSC calibration on Intel Atom SoC platforms. + * + * TSC in Intel Atom SoC runs at a constant rate which can be figured + * by this formula: + * <maximum core-clock to bus-clock ratio> * <maximum resolved frequency> + * See Intel 64 and IA-32 System Programming Guid section 16.12 and 30.11.5 + * for details. + * Especially some Intel Atom SoCs don't have PIT(i8254) or HPET, so MSR + * based calibration is the only option. + * + * + * Copyright (C) 2013 Intel Corporation + * Author: Bin Gao <bin.gao@intel.com> + * + * This file is released under the GPLv2. + */ + +#include <linux/kernel.h> +#include <asm/processor.h> +#include <asm/setup.h> +#include <asm/apic.h> +#include <asm/param.h> + +/* CPU reference clock frequency: in KHz */ +#define FREQ_83 83200 +#define FREQ_100 99840 +#define FREQ_133 133200 +#define FREQ_166 166400 + +#define MAX_NUM_FREQS 8 + +/* + * According to Intel 64 and IA-32 System Programming Guide, + * if MSR_PERF_STAT[31] is set, the maximum resolved bus ratio can be + * read in MSR_PLATFORM_ID[12:8], otherwise in MSR_PERF_STAT[44:40]. + * Unfortunately some Intel Atom SoCs aren't quite compliant to this, + * so we need manually differentiate SoC families. This is what the + * field msr_plat does. + */ +struct freq_desc { + u8 x86_family; /* CPU family */ + u8 x86_model; /* model */ + u8 msr_plat; /* 1: use MSR_PLATFORM_INFO, 0: MSR_IA32_PERF_STATUS */ + u32 freqs[MAX_NUM_FREQS]; +}; + +static struct freq_desc freq_desc_tables[] = { + /* PNW */ + { 6, 0x27, 0, { 0, 0, 0, 0, 0, FREQ_100, 0, FREQ_83 } }, + /* CLV+ */ + { 6, 0x35, 0, { 0, FREQ_133, 0, 0, 0, FREQ_100, 0, FREQ_83 } }, + /* TNG */ + { 6, 0x4a, 1, { 0, FREQ_100, FREQ_133, 0, 0, 0, 0, 0 } }, + /* VLV2 */ + { 6, 0x37, 1, { 0, FREQ_100, FREQ_133, FREQ_166, 0, 0, 0, 0 } }, + /* ANN */ + { 6, 0x5a, 1, { FREQ_83, FREQ_100, FREQ_133, FREQ_100, 0, 0, 0, 0 } }, +}; + +static int match_cpu(u8 family, u8 model) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(freq_desc_tables); i++) { + if ((family == freq_desc_tables[i].x86_family) && + (model == freq_desc_tables[i].x86_model)) + return i; + } + + return -1; +} + +/* Map CPU reference clock freq ID(0-7) to CPU reference clock freq(KHz) */ +#define id_to_freq(cpu_index, freq_id) \ + (freq_desc_tables[cpu_index].freqs[freq_id]) + +/* + * Do MSR calibration only for known/supported CPUs. + * Return values: + * -1: CPU is unknown/unsupported for MSR based calibration + * 0: CPU is known/supported, but calibration failed + * 1: CPU is known/supported, and calibration succeeded + */ +int try_msr_calibrate_tsc(unsigned long *fast_calibrate) +{ + int cpu_index; + u32 lo, hi, ratio, freq_id, freq; + + cpu_index = match_cpu(boot_cpu_data.x86, boot_cpu_data.x86_model); + if (cpu_index < 0) + return -1; + + *fast_calibrate = 0; + + if (freq_desc_tables[cpu_index].msr_plat) { + rdmsr(MSR_PLATFORM_INFO, lo, hi); + ratio = (lo >> 8) & 0x1f; + } else { + rdmsr(MSR_IA32_PERF_STATUS, lo, hi); + ratio = (hi >> 8) & 0x1f; + } + pr_info("Maximum core-clock to bus-clock ratio: 0x%x\n", ratio); + + if (!ratio) + return 0; + + /* Get FSB FREQ ID */ + rdmsr(MSR_FSB_FREQ, lo, hi); + freq_id = lo & 0x7; + freq = id_to_freq(cpu_index, freq_id); + pr_info("Resolved frequency ID: %u, frequency: %u KHz\n", + freq_id, freq); + if (!freq) + return 0; + + /* TSC frequency = maximum resolved freq * maximum resolved bus ratio */ + *fast_calibrate = freq * ratio; + pr_info("TSC runs at %lu KHz\n", *fast_calibrate); + +#ifdef CONFIG_X86_LOCAL_APIC + lapic_timer_frequency = (freq * 1000) / HZ; + pr_info("lapic_timer_frequency = %d\n", lapic_timer_frequency); +#endif + + return 1; +} |
