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@@ -472,7 +472,7 @@ Offset Size Description )
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13h 3 BYTEs "JPN"
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```
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-Next we call the `set_fs` routine and pass the value of the `es` register to it. Implementation of `set_fs` is pretty simple:
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+Next we call the `set_fs` routine and pass the value of the `es` register to it. The implementation of `set_fs` is pretty simple:
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```c
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static inline void set_fs(u16 seg)
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@@ -483,15 +483,15 @@ static inline void set_fs(u16 seg)
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This function contains inline assembly which gets the value of the `seg` parameter and puts it into the `fs` register. There are many functions in [boot.h](https://github.com/torvalds/linux/blob/master/arch/x86/boot/boot.h) like `set_fs`, for example `set_gs`, `fs`, `gs` for reading a value in it etc...
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-At the end of `query_mca` it just copies the table which pointed to by `es:bx` to the `boot_params.sys_desc_table`.
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+At the end of `query_mca` it just copies the table pointed to by `es:bx` to the `boot_params.sys_desc_table`.
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The next step is getting [Intel SpeedStep](http://en.wikipedia.org/wiki/SpeedStep) information by calling the `query_ist` function. First of all it checks the CPU level and if it is correct, calls `0x15` for getting info and saves the result to `boot_params`.
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-The following [query_apm_bios](https://github.com/torvalds/linux/blob/master/arch/x86/boot/apm.c#L21) function gets [Advanced Power Management](http://en.wikipedia.org/wiki/Advanced_Power_Management) information from the BIOS. `query_apm_bios` calls the `0x15` BIOS interruption too, but with `ah` = `0x53` to check `APM` installation. After the `0x15` execution, `query_apm_bios` functions checks `PM` signature (it must be `0x504d`), carry flag (it must be 0 if `APM` supported) and value of the `cx` register (if it's 0x02, protected mode interface is supported).
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+The following [query_apm_bios](https://github.com/torvalds/linux/blob/master/arch/x86/boot/apm.c#L21) function gets [Advanced Power Management](http://en.wikipedia.org/wiki/Advanced_Power_Management) information from the BIOS. `query_apm_bios` calls the `0x15` BIOS interruption too, but with `ah` = `0x53` to check `APM` installation. After the `0x15` execution, `query_apm_bios` functions check the `PM` signature (it must be `0x504d`), carry flag (it must be 0 if `APM` supported) and value of the `cx` register (if it's 0x02, protected mode interface is supported).
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-Next it calls the `0x15` again, but with `ax = 0x5304` for disconnecting the `APM` interface and connecting the 32-bit protected mode interface. In the end it fills `boot_params.apm_bios_info` with values obtained from the BIOS.
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+Next it calls `0x15` again, but with `ax = 0x5304` for disconnecting the `APM` interface and connecting the 32-bit protected mode interface. In the end it fills `boot_params.apm_bios_info` with values obtained from the BIOS.
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-Note that `query_apm_bios` will be executed only if `CONFIG_APM` or `CONFIG_APM_MODULE` was set in configuration file:
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+Note that `query_apm_bios` will be executed only if `CONFIG_APM` or `CONFIG_APM_MODULE` was set in the configuration file:
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```C
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#if defined(CONFIG_APM) || defined(CONFIG_APM_MODULE)
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@@ -501,7 +501,7 @@ Note that `query_apm_bios` will be executed only if `CONFIG_APM` or `CONFIG_APM_
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The last is the [`query_edd`](https://github.com/torvalds/linux/blob/master/arch/x86/boot/edd.c#L122) function, which queries `Enhanced Disk Drive` information from the BIOS. Let's look into the `query_edd` implementation.
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-First of all it reads the [edd](https://github.com/torvalds/linux/blob/master/Documentation/kernel-parameters.txt#L1023) option from kernel's command line and if it was set to `off` then `query_edd` just returns.
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+First of all it reads the [edd](https://github.com/torvalds/linux/blob/master/Documentation/kernel-parameters.txt#L1023) option from the kernel's command line and if it was set to `off` then `query_edd` just returns.
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If EDD is enabled, `query_edd` goes over BIOS-supported hard disks and queries EDD information in the following loop:
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ruthgrace