[U-Boot] [PATCH 2/2] x86: Install a default e820 table in the __weak install_e820_map()

[Simon Glass]

Hi Bin,

On 21 April 2015 at 19:01, Bin Meng <bmeng.cn at gmail.com> wrote:
> Hi Simon,
>
> On Tue, Apr 21, 2015 at 9:52 PM, Simon Glass <sjg at chromium.org> wrote:
>> Hi Bin,
>>
>> On 20 April 2015 at 22:21, Bin Meng <bmeng.cn at gmail.com> wrote:
>>> Create a default e820 table with 3 entries which is enough to boot
>>> a Linux kernel.
>>>
>>> Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
>>> ---
>>>
>>>  arch/x86/lib/zimage.c | 29 ++++++++++++++++++++++-------
>>>  1 file changed, 22 insertions(+), 7 deletions(-)
>>>
>>> diff --git a/arch/x86/lib/zimage.c b/arch/x86/lib/zimage.c
>>> index 566b048..c3f8a73 100644
>>> --- a/arch/x86/lib/zimage.c
>>> +++ b/arch/x86/lib/zimage.c
>>> @@ -25,6 +25,8 @@
>>>  #endif
>>>  #include <linux/compiler.h>
>>>
>>> +DECLARE_GLOBAL_DATA_PTR;
>>> +
>>>  /*
>>>   * Memory lay-out:
>>>   *
>>> @@ -40,16 +42,29 @@
>>>
>>>  #define COMMAND_LINE_SIZE      2048
>>>
>>> -unsigned generic_install_e820_map(unsigned max_entries,
>>> -                                 struct e820entry *entries)
>>> +/*
>>> + * Install a default e820 table with 3 entries as follows:
>>> + *
>>> + *     0x000000-0x0a0000       Useable RAM
>>> + *     0x0a0000-0x100000       Reserved for ISA
>>> + *     0x100000-gd->ram_size   Useable RAM
>>> + */
>>> +__weak unsigned install_e820_map(unsigned max_entries,
>>> +                                struct e820entry *entries)
>>>  {
>>> -       return 0;
>>> +       entries[0].addr = 0;
>>> +       entries[0].size = ISA_START_ADDRESS;
>>> +       entries[0].type = E820_RAM;
>>> +       entries[1].addr = ISA_START_ADDRESS;
>>> +       entries[1].size = ISA_END_ADDRESS - ISA_START_ADDRESS;
>>> +       entries[1].type = E820_RESERVED;
>>> +       entries[2].addr = ISA_END_ADDRESS;
>>> +       entries[2].size = gd->ram_size - ISA_END_ADDRESS;
>>> +       entries[2].type = E820_RAM;
>>> +
>>> +       return 3;
>>>  }
>>>
>>> -unsigned install_e820_map(unsigned max_entries,
>>> -                         struct e820entry *entries)
>>> -       __attribute__((weak, alias("generic_install_e820_map")));
>>> -
>>>  static void build_command_line(char *command_line, int auto_boot)
>>>  {
>>>         char *env_command_line;
>>> --
>>> 1.8.2.1
>>>
>>
>> Why is this code sitting in zimage.c? Should it be used with bootm also?
>
> Sorry I am not sure I understand your point. setup_zimage() is called
> by boot_prep_linux() in bootm.c.

I mean that install_e820_map() seems to be unrelated to zimage, and is
perhaps better kept in a more generic place, perhaps
arch/x86/lib/bootm.c or even arch/x86/lib/e820. Anyway let's apply
this and we can figure that out later.

Acked-by: Simon Glass <sjg at chromium.org>

Regards,
Simon