Re: [PATCH 2/2] msm: Support DEBUG_LL on MSM8660 and MSM8960

From: Nicolas Pitre
Date: Thu Sep 29 2011 - 00:21:39 EST


On Wed, 28 Sep 2011, Stephen Boyd wrote:

> Add support for DEBUG_LL on the 8660 and 8960 development boards.
> While we're here, cleanup the uncompress.h code a bit.
>
> Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
> ---

[...]

> .macro senduart,rd,rx
> +#ifdef CONFIG_MSM_HAS_DEBUG_UART_HS
> + @ Clear TX_READY by writing to the UARTDM_CR register
> + mov r12, #0x300
> + str r12, [\rx, #0x10]
> + @ Write 0x1 to NCF register
> + mov r12, #0x1
> + str r12, [\rx, #0x40]
> + @ UARTDM reg. Read to induce delay
> + ldr r12, [\rx, #0x08]
> + @ Write the 1 character to UARTDM_TF
> + str \rd, [\rx, #0x70]

This is a really bad idea to pick a register (r12) when the calling code
is completely unaware of that. This _will_ break on you someday.

Except for the last line, why didn't you simply fold this code into the
waituart macro instead?


Nicolas
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