Re: [PATCH] x86: Add PCI extended config space access for AMD Barcelona

["Yinghai Lu" <yhlu.kernel@gmail.com>]

On Mon, Sep 3, 2007 at 1:17 AM, Robert Richter <robert.richter@amd.com> wrote:
> This patch implements PCI extended configuration space access for
> AMD's Barcelona CPUs. It extends the method using CF8/CFC IO
> addresses. An x86 capability bit has been introduced that is set for
> CPUs supporting PCI extended config space accesses.
>
> Signed-off-by: Robert Richter <robert.richter@amd.com>
> ---
>  arch/x86/kernel/cpu/amd.c    |    4 ++++
>  arch/x86/kernel/setup.c      |   13 +++++++++++++
>  arch/x86/kernel/setup.h      |   26 ++++++++++++++++++++++++++
>  arch/x86/kernel/setup_64.c   |    5 +++++
>  arch/x86/pci/direct.c        |   21 +++++++++++++++------
>  include/asm-x86/cpufeature.h |    2 ++
>  6 files changed, 65 insertions(+), 6 deletions(-)
>  create mode 100644 arch/x86/kernel/setup.h
>
> diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
> index 2458668..99221f9 100644
> --- a/arch/x86/kernel/cpu/amd.c
> +++ b/arch/x86/kernel/cpu/amd.c
> @@ -6,6 +6,7 @@
>  #include <asm/apic.h>
>
>  #include <mach_apic.h>
> +#include "../setup.h"
>  #include "cpu.h"
>
>  /*
> @@ -308,6 +309,9 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
>
>        if (cpu_has_xmm2)
>                set_cpu_cap(c, X86_FEATURE_MFENCE_RDTSC);
> +
> +       if (c->x86 == 0x10)
> +               amd_enable_pci_ext_cfg(c);
>  }
>
>  static unsigned int __cpuinit amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
> index 6f80b85..d8f1712 100644
> --- a/arch/x86/kernel/setup.c
> +++ b/arch/x86/kernel/setup.c
> @@ -136,4 +136,17 @@ void __init setup_per_cpu_areas(void)
>        setup_cpumask_of_cpu();
>  }
>
> +#define ENABLE_CF8_EXT_CFG      (1ULL << 46)
> +
> +void __cpuinit amd_enable_pci_ext_cfg(struct cpuinfo_x86 *c)
> +{
> +       u64 reg;
> +       rdmsrl(MSR_AMD64_NB_CFG, reg);
> +       if (!(reg & ENABLE_CF8_EXT_CFG)) {
> +               reg |= ENABLE_CF8_EXT_CFG;
> +               wrmsrl(MSR_AMD64_NB_CFG, reg);
> +       }
> +       set_cpu_cap(c, X86_FEATURE_PCI_EXT_CFG);
> +}
> +
>  #endif
> diff --git a/arch/x86/kernel/setup.h b/arch/x86/kernel/setup.h
> new file mode 100644
> index 0000000..66cc2c7
> --- /dev/null
> +++ b/arch/x86/kernel/setup.h
> @@ -0,0 +1,26 @@
> +/*
> + * Internal declarations for shared x86 setup code.
> + *
> + * Copyright (c) 2008 Advanced Micro Devices, Inc.
> + * Contributed by Robert Richter <robert.richter@amd.com>
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of version 2 of the GNU General Public
> + * License as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that 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.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
> + * 02111-1307 USA
> + */
> +
> +#ifndef _ARCH_X86_KERNEL_SETUP_H
> +
> +extern void __cpuinit amd_enable_pci_ext_cfg(struct cpuinfo_x86 *c);
> +
> +#endif /* _ARCH_X86_KERNEL_SETUP_H */
> diff --git a/arch/x86/kernel/setup_64.c b/arch/x86/kernel/setup_64.c
> index 6dff128..fdd2469 100644
> --- a/arch/x86/kernel/setup_64.c
> +++ b/arch/x86/kernel/setup_64.c
> @@ -72,6 +72,8 @@
>  #include <asm/trampoline.h>
>  #include <asm/pat.h>
>
> +#include "setup.h"
> +
>  #include <mach_apic.h>
>  #ifdef CONFIG_PARAVIRT
>  #include <asm/paravirt.h>
> @@ -790,6 +792,9 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
>        if (c->x86 == 0x10)
>                fam10h_check_enable_mmcfg();
>
> +       if (c->x86 == 0x10)
> +               amd_enable_pci_ext_cfg(c);
> +
>        if (amd_apic_timer_broken())
>                disable_apic_timer = 1;
>
> diff --git a/arch/x86/pci/direct.c b/arch/x86/pci/direct.c
> index 21d1e0e..27d61b6 100644
> --- a/arch/x86/pci/direct.c
> +++ b/arch/x86/pci/direct.c
> @@ -8,18 +8,21 @@
>  #include "pci.h"
>
>  /*
> - * Functions for accessing PCI configuration space with type 1 accesses
> + * Functions for accessing PCI base (first 256 bytes) and extended
> + * (4096 bytes per PCI function) configuration space with type 1
> + * accesses.
>  */
>
>  #define PCI_CONF1_ADDRESS(bus, devfn, reg) \
> -       (0x80000000 | (bus << 16) | (devfn << 8) | (reg & ~3))
> +       (0x80000000 | ((reg & 0xF00) << 16) | (bus << 16) \
> +       | (devfn << 8) | (reg & 0xFC))
>
>  static int pci_conf1_read(unsigned int seg, unsigned int bus,
>                          unsigned int devfn, int reg, int len, u32 *value)
>  {
>        unsigned long flags;
>
> -       if ((bus > 255) || (devfn > 255) || (reg > 255)) {
> +       if ((bus > 255) || (devfn > 255) || (reg > 4095)) {
>                *value = -1;
>                return -EINVAL;
>        }
> @@ -50,7 +53,7 @@ static int pci_conf1_write(unsigned int seg, unsigned int bus,
>  {
>        unsigned long flags;
>
> -       if ((bus > 255) || (devfn > 255) || (reg > 255))
> +       if ((bus > 255) || (devfn > 255) || (reg > 4095))
>                return -EINVAL;
>
>        spin_lock_irqsave(&pci_config_lock, flags);
> @@ -260,10 +263,16 @@ void __init pci_direct_init(int type)
>                return;
>        printk(KERN_INFO "PCI: Using configuration type %d for base access\n",
>                 type);
> -       if (type == 1)
> +       if (type == 1) {
>                raw_pci_ops = &pci_direct_conf1;
> -       else
> +               if (!raw_pci_ext_ops && cpu_has_pci_ext_cfg) {
> +                       printk(KERN_INFO "PCI: Using configuration type 1 "
> +                              "for extended access\n");
> +                       raw_pci_ext_ops = &pci_direct_conf1;

can you add extra pci_direct_ext_conf1 intead?

so don't need change reg size in pci_direct_conf1

also if could avoid cpu_has_pci_ext_cfg, it would be great...

YH

> +               }
> +       } else {
>                raw_pci_ops = &pci_direct_conf2;
> +       }
>  }
>
>  int __init pci_direct_probe(void)
> diff --git a/include/asm-x86/cpufeature.h b/include/asm-x86/cpufeature.h
> index 0d609c8..40fcbba 100644
> --- a/include/asm-x86/cpufeature.h
> +++ b/include/asm-x86/cpufeature.h
> @@ -79,6 +79,7 @@
>  #define X86_FEATURE_REP_GOOD   (3*32+16) /* rep microcode works well on this CPU */
>  #define X86_FEATURE_MFENCE_RDTSC (3*32+17) /* Mfence synchronizes RDTSC */
>  #define X86_FEATURE_LFENCE_RDTSC (3*32+18) /* Lfence synchronizes RDTSC */
> +#define X86_FEATURE_PCI_EXT_CFG        (3*32+19) /* PCI extended cfg access */
>
>  /* Intel-defined CPU features, CPUID level 0x00000001 (ecx), word 4 */
>  #define X86_FEATURE_XMM3       (4*32+ 0) /* Streaming SIMD Extensions-3 */
> @@ -187,6 +188,7 @@ extern const char * const x86_power_flags[32];
>  #define cpu_has_gbpages                boot_cpu_has(X86_FEATURE_GBPAGES)
>  #define cpu_has_arch_perfmon   boot_cpu_has(X86_FEATURE_ARCH_PERFMON)
>  #define cpu_has_pat            boot_cpu_has(X86_FEATURE_PAT)
> +#define cpu_has_pci_ext_cfg    boot_cpu_has(X86_FEATURE_PCI_EXT_CFG)
>
>  #if defined(CONFIG_X86_INVLPG) || defined(CONFIG_X86_64)
>  # define cpu_has_invlpg                1
> --
> 1.5.3.7
>
>
>