Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull Intel SoC changes from Ingo Molnar:
 "Improved Intel SoC platform support"

* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, tsc, apic: Unbreak static (MSR) calibration when CONFIG_X86_LOCAL_APIC=n
  x86, tsc: Add static (MSR) TSC calibration on Intel Atom SoCs
  arch: x86: New MailBox support driver for Intel SOC's
This commit is contained in:
Linus Torvalds 2014-01-20 12:09:31 -08:00
commit 74e8ee8262
7 changed files with 466 additions and 1 deletions

View file

@ -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"

View file

@ -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 */

View file

@ -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 */

View file

@ -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

226
arch/x86/kernel/iosf_mbi.c Normal file
View file

@ -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");

View file

@ -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);

127
arch/x86/kernel/tsc_msr.c Normal file
View file

@ -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;
}