[U-Boot] [PATCH v2 26/30] x86: Add LAPIC setup code

[Simon Glass]

Hi Bin,

On 14 November 2014 21:01, Bin Meng <bmeng.cn at gmail.com> wrote:
> Hi Simon,
>
> On Sat, Nov 15, 2014 at 9:18 AM, Simon Glass <sjg at chromium.org> wrote:
>> Add code to set up the Local Advanced Peripheral Interrupt Controller.
>>
>> Signed-off-by: Simon Glass <sjg at chromium.org>
>> ---
>>
>> Changes in v2:
>> - Remove use of __PRE_RAM__ define
>> - Use existing lapic_setup() code instead of duplicating it
>>
>>  arch/x86/cpu/Makefile        |   1 +
>>  arch/x86/cpu/lapic.c         |  62 +++++++++++++++++++++
>>  arch/x86/include/asm/lapic.h | 125 +++++++++++++++++++++++++++++++++++++++++--
>>  arch/x86/include/asm/post.h  |   1 +
>>  4 files changed, 186 insertions(+), 3 deletions(-)
>>  create mode 100644 arch/x86/cpu/lapic.c
>>
>> diff --git a/arch/x86/cpu/Makefile b/arch/x86/cpu/Makefile
>> index 1327f08..adfd258 100644
>> --- a/arch/x86/cpu/Makefile
>> +++ b/arch/x86/cpu/Makefile
>> @@ -11,5 +11,6 @@
>>  extra-y        = start.o
>>  obj-$(CONFIG_X86_RESET_VECTOR) += resetvec.o start16.o
>>  obj-y  += interrupts.o cpu.o call64.o
>> +obj-y += lapic.o
>>  obj-$(CONFIG_PCI) += pci.o
>>  obj-y += turbo.o
>> diff --git a/arch/x86/cpu/lapic.c b/arch/x86/cpu/lapic.c
>> new file mode 100644
>> index 0000000..4d14a8d
>> --- /dev/null
>> +++ b/arch/x86/cpu/lapic.c
>> @@ -0,0 +1,62 @@
>> +/*
>> + * From coreboot file of same name
>> + *
>> + * Copyright (C) 2008-2009 coresystems GmbH
>> + * Copyright (C) 2014 Google, Inc
>> + *
>> + * SPDX-License-Identifier:    GPL-2.0
>> + */
>> +
>> +#include <common.h>
>> +#include <asm/msr.h>
>> +#include <asm/io.h>
>> +#include <asm/lapic.h>
>> +#include <asm/post.h>
>> +
>> +void lapic_setup(void)
>> +{
>> +#if NEED_LAPIC == 1
>> +       /* Only Pentium Pro and later have those MSR stuff */
>> +       debug("Setting up local apic: ");
>> +
>> +       /* Enable the local apic */
>> +       enable_lapic();
>> +
>> +       /*
>> +        * Set Task Priority to 'accept all'.
>> +        */
>> +       lapic_write_around(LAPIC_TASKPRI,
>> +                          lapic_read_around(LAPIC_TASKPRI) & ~LAPIC_TPRI_MASK);
>> +
>> +       /* Put the local apic in virtual wire mode */
>> +       lapic_write_around(LAPIC_SPIV, (lapic_read_around(LAPIC_SPIV) &
>> +                               ~(LAPIC_VECTOR_MASK)) | LAPIC_SPIV_ENABLE);
>> +       lapic_write_around(LAPIC_LVT0, (lapic_read_around(LAPIC_LVT0) &
>> +                       ~(LAPIC_LVT_MASKED | LAPIC_LVT_LEVEL_TRIGGER |
>> +                         LAPIC_LVT_REMOTE_IRR | LAPIC_INPUT_POLARITY |
>> +                         LAPIC_SEND_PENDING | LAPIC_LVT_RESERVED_1 |
>> +                         LAPIC_DELIVERY_MODE_MASK)) |
>> +                       (LAPIC_LVT_REMOTE_IRR | LAPIC_SEND_PENDING |
>> +                        LAPIC_DELIVERY_MODE_EXTINT));
>> +       lapic_write_around(LAPIC_LVT1, (lapic_read_around(LAPIC_LVT1) &
>> +                       ~(LAPIC_LVT_MASKED | LAPIC_LVT_LEVEL_TRIGGER |
>> +                         LAPIC_LVT_REMOTE_IRR | LAPIC_INPUT_POLARITY |
>> +                         LAPIC_SEND_PENDING | LAPIC_LVT_RESERVED_1 |
>> +                         LAPIC_DELIVERY_MODE_MASK)) |
>> +               (LAPIC_LVT_REMOTE_IRR | LAPIC_SEND_PENDING |
>> +                       LAPIC_DELIVERY_MODE_NMI));
>> +
>> +       debug("apic_id: 0x%02lx, ", lapicid());
>> +#else /* !NEED_LLAPIC */
>> +       /* Only Pentium Pro and later have those MSR stuff */
>> +       msr_t msr;
>> +
>> +       debug("Disabling local apic:");
>> +
>> +       msr = msr_read(LAPIC_BASE_MSR);
>> +       msr.lo &= ~LAPIC_BASE_MSR_ENABLE;
>> +       msr_write(LAPIC_BASE_MSR, msr);
>
> Seems you missed my previous comments about replacing above with
> disable_lapic() which is defined in lapic.h.

No, it is there. This function calls enable_lapic() then does some
other things too.

Regards,
Simon