[U-Boot] [PATCH v3] mx25: Clean up lowlevel_init
Stefano Babic
sbabic at denx.de
Tue Oct 2 10:12:50 CEST 2012
On 01/10/2012 21:50, Benoît Thébaudeau wrote:
> Hi Stefano,
>
> On Sunday, September 30, 2012 3:47:12 PM, Benoît Thébaudeau wrote:
>> Hi Stefano,
>>
>> On Sunday, September 30, 2012 3:04:14 PM, Stefano Babic wrote:
>>> On 20/08/2012 21:00, Benoît Thébaudeau wrote:
>>>> Clean up mx25 lowlevel_init:
>>>> - Add comments.
>>>> - Do not use write32 repeatedly with the same value in order not
>>>> to increase
>>>> code size.
>>>> - Make register values configurable.
>>>> - Use macro parameters with default values instead of literal
>>>> constants.
>>>> - Use defined macros instead of duplicating code.
>>>>
>>>> Signed-off-by: Benoît Thébaudeau <benoit.thebaudeau at advansee.com>
>>>> Cc: Stefano Babic <sbabic at denx.de>
>>>> Cc: John Rigby <jcrigby at gmail.com>
>>>> Cc: Matthias Weisser <weisserm at arcor.de>
>>>> ---
>>>
>>> Hi Benoît,
>>>
>>>> Changes for v2:
>>>> - Use macro arguments with default values instead of #define's.
>>>> Changes for v3:
>>>> - Fix comment for default MAX MPR value.
>>>>
>>>> .../arch/arm/include/asm/arch-mx25/macro.h | 87
>>>> +++++++++++++++-----
>>>> .../board/karo/tx25/lowlevel_init.S | 34
>>>> +-------
>>>> 2 files changed, 68 insertions(+), 53 deletions(-)
>>>>
>>>> diff --git
>>>> u-boot-4d3c95f.orig/arch/arm/include/asm/arch-mx25/macro.h
>>>> u-boot-4d3c95f/arch/arm/include/asm/arch-mx25/macro.h
>>>> index 3b694da..56cae36 100644
>>>> --- u-boot-4d3c95f.orig/arch/arm/include/asm/arch-mx25/macro.h
>>>> +++ u-boot-4d3c95f/arch/arm/include/asm/arch-mx25/macro.h
>>>> @@ -32,32 +32,75 @@
>>>>
>>>> #include <asm/arch/imx-regs.h>
>>>> #include <generated/asm-offsets.h>
>>>> +#include <asm/macro.h>
>>>>
>>>> -.macro init_aips
>>>> - write32 IMX_AIPS1_BASE + AIPS_MPR_0_7, 0x77777777
>>>> - write32 IMX_AIPS1_BASE + AIPS_MPR_8_15, 0x77777777
>>>> - write32 IMX_AIPS2_BASE + AIPS_MPR_0_7, 0x77777777
>>>> - write32 IMX_AIPS2_BASE + AIPS_MPR_8_15, 0x77777777
>>>> +/*
>>>> + * AIPS setup - Only setup MPROTx registers.
>>>> + * The PACR default values are good.
>>>> + *
>>>> + * Default argument values:
>>>> + * - MPR: Set all MPROTx to be non-bufferable, trusted for R/W,
>>>> not forced to
>>>> + * user-mode.
>>>> + */
>>>> +.macro init_aips mpr=0x77777777
>>>> + ldr r0, =IMX_AIPS1_BASE
>>>> + ldr r1, =\mpr
>>>> + str r1, [r0, #AIPS_MPR_0_7]
>>>> + str r1, [r0, #AIPS_MPR_8_15]
>>>> + ldr r2, =IMX_AIPS2_BASE
>>>> + str r1, [r2, #AIPS_MPR_0_7]
>>>> + str r1, [r2, #AIPS_MPR_8_15]
>>>> .endm
>>>>
>>>> -.macro init_max
>>>> - write32 IMX_MAX_BASE + MAX_MPR0, 0x43210
>>>> - write32 IMX_MAX_BASE + MAX_MPR1, 0x43210
>>>> - write32 IMX_MAX_BASE + MAX_MPR2, 0x43210
>>>> - write32 IMX_MAX_BASE + MAX_MPR3, 0x43210
>>>> - write32 IMX_MAX_BASE + MAX_MPR4, 0x43210
>>>> -
>>>> - write32 IMX_MAX_BASE + MAX_SGPCR0, 0x10
>>>> - write32 IMX_MAX_BASE + MAX_SGPCR1, 0x10
>>>> - write32 IMX_MAX_BASE + MAX_SGPCR2, 0x10
>>>> - write32 IMX_MAX_BASE + MAX_SGPCR3, 0x10
>>>> - write32 IMX_MAX_BASE + MAX_SGPCR4, 0x10
>>>> +/*
>>>> + * MAX (Multi-Layer AHB Crossbar Switch) setup
>>>> + *
>>>> + * Default argument values:
>>>> + * - MPR: priority is IAHB > DAHB > USBOTG > RTIC > eSDHC2/SDMA
>>>> + * - SGPCR: always park on last master
>>>> + * - MGPCR: restore default values
>>>> + */
>>>> +.macro init_max mpr=0x00043210, sgpcr=0x00000010,
>>>> mgpcr=0x00000000
>>>> + ldr r0, =IMX_MAX_BASE
>>>> + ldr r1, =\mpr
>>>> + str r1, [r0, #MAX_MPR0] /* for S0 */
>>>> + str r1, [r0, #MAX_MPR1] /* for S1 */
>>>> + str r1, [r0, #MAX_MPR2] /* for S2 */
>>>> + str r1, [r0, #MAX_MPR3] /* for S3 */
>>>> + str r1, [r0, #MAX_MPR4] /* for S4 */
>>>> + ldr r1, =\sgpcr
>>>> + str r1, [r0, #MAX_SGPCR0] /* for S0 */
>>>> + str r1, [r0, #MAX_SGPCR1] /* for S1 */
>>>> + str r1, [r0, #MAX_SGPCR2] /* for S2 */
>>>> + str r1, [r0, #MAX_SGPCR3] /* for S3 */
>>>> + str r1, [r0, #MAX_SGPCR4] /* for S4 */
>>>> + ldr r1, =\mgpcr
>>>> + str r1, [r0, #MAX_MGPCR0] /* for M0 */
>>>> + str r1, [r0, #MAX_MGPCR1] /* for M1 */
>>>> + str r1, [r0, #MAX_MGPCR2] /* for M2 */
>>>> + str r1, [r0, #MAX_MGPCR3] /* for M3 */
>>>> + str r1, [r0, #MAX_MGPCR4] /* for M4 */
>>>> +.endm
>>>>
>>>> - write32 IMX_MAX_BASE + MAX_MGPCR0, 0x0
>>>> - write32 IMX_MAX_BASE + MAX_MGPCR1, 0x0
>>>> - write32 IMX_MAX_BASE + MAX_MGPCR2, 0x0
>>>> - write32 IMX_MAX_BASE + MAX_MGPCR3, 0x0
>>>> - write32 IMX_MAX_BASE + MAX_MGPCR4, 0x0
>>>> +/*
>>>> + * M3IF setup
>>>> + *
>>>> + * Default argument values:
>>>> + * - CTL:
>>>> + * MRRP[0] = LCDC on priority list (1 << 0) = 0x00000001
>>>> + * MRRP[1] = MAX1 not on priority list (0 << 1) = 0x00000000
>>>> + * MRRP[2] = MAX0 not on priority list (0 << 2) = 0x00000000
>>>> + * MRRP[3] = USBH not on priority list (0 << 3) = 0x00000000
>>>> + * MRRP[4] = SDMA not on priority list (0 << 4) = 0x00000000
>>>> + * MRRP[5] = eSDHC1/ATA/FEC not on priority list (0 << 5) =
>>>> 0x00000000
>>>> + * MRRP[6] = LCDC/SLCDC/MAX2 not on priority list (0 << 6) =
>>>> 0x00000000
>>>> + * MRRP[7] = CSI not on priority list (0 << 7) = 0x00000000
>>>> + * ------------
>>>> + * 0x00000001
>>>> + */
>>>> +.macro init_m3if ctl=0x00000001
>>>> + /* M3IF Control Register (M3IFCTL) */
>>>> + write32 IMX_M3IF_CTRL_BASE, \ctl
>>>> .endm
>>>>
>>>> #endif /* __ASSEMBLY__ */
>>>> diff --git u-boot-4d3c95f.orig/board/karo/tx25/lowlevel_init.S
>>>> u-boot-4d3c95f/board/karo/tx25/lowlevel_init.S
>>>> index 823df10..0421237 100644
>>>> --- u-boot-4d3c95f.orig/board/karo/tx25/lowlevel_init.S
>>>> +++ u-boot-4d3c95f/board/karo/tx25/lowlevel_init.S
>>>> @@ -22,37 +22,7 @@
>>>> */
>>>>
>>>> #include <asm/macro.h>
>>>> -
>>>> -.macro init_aips
>>>> - write32 0x43f00000, 0x77777777
>>>> - write32 0x43f00004, 0x77777777
>>>> - write32 0x43f00000, 0x77777777
>>>> - write32 0x53f00004, 0x77777777
>>>> -.endm
>>>> -
>>>> -.macro init_max
>>>> - write32 0x43f04000, 0x43210
>>>> - write32 0x43f04100, 0x43210
>>>> - write32 0x43f04200, 0x43210
>>>> - write32 0x43f04300, 0x43210
>>>> - write32 0x43f04400, 0x43210
>>>> -
>>>> - write32 0x43f04010, 0x10
>>>> - write32 0x43f04110, 0x10
>>>> - write32 0x43f04210, 0x10
>>>> - write32 0x43f04310, 0x10
>>>> - write32 0x43f04410, 0x10
>>>> -
>>>> - write32 0x43f04800, 0x0
>>>> - write32 0x43f04900, 0x0
>>>> - write32 0x43f04a00, 0x0
>>>> - write32 0x43f04b00, 0x0
>>>> - write32 0x43f04c00, 0x0
>>>> -.endm
>>>> -
>>>> -.macro init_m3if
>>>> - write32 0xb8003000, 0x1
>>>> -.endm
>>>> +#include <asm/arch/macro.h>
>>>>
>>>> .macro init_clocks
>>>> /*
>>>> @@ -64,6 +34,8 @@
>>>> * 0x00600000 makes CLKO parent clk the USB clk
>>>> */
>>>> write32 0x53f80064, 0x45600000
>>>> +
>>>> + /* CCTL: ARM = 399 MHz, AHB = 133 MHz */
>>>> write32 0x53f80008, 0x20034000
>>>>
>>>> /*
>>>>
>>>
>>> You only moved code and set default values for macros: I do not see
>>> issues. But checkpatch reports several errors, and, even if some of
>>> them
>>> can be related to the fact this file is in assembly, most of them
>>> can
>>> be
>>> fixed.
>>>
>>> Could you take a look ?
>>
>> Will do.
>
> These errors can be classified into 3 categories:
>
> 1. "spaces required around that '=' (ctx:WxV)":
> 1.1. For macro argument default value, e.g.:
> +.macro init_aips mpr=0x77777777
> ^
> This is the convention used by gas' manual. It is also used by U-Boot, e.g. in
> arch/arm/lib/memcpy.S. The coma is optional to separate the definition of macro
> arguments, in which case not using extra spaces makes even more sense.
Agree.
>
> 1.2. For register assignment, e.g.:
> + ldr r0, =IMX_AIPS1_BASE
> ^
> This is the convention currently used by U-Boot ARM asm code. That would look
> weird an unusual with an extra space.
This is the convention I use, too. It makes no sense to add an extra space.
>
> 2. "space prohibited before open square bracket '['", e.g.:
> + str r1, [r0, #AIPS_MPR_0_7]
> This is the convention currently used by U-Boot ARM asm code. The purpose of
> this rule for checkpatch is clearly for array subscripts, which has nothing to
> do with this line. Here, the space is good to separate instruction arguments.
Right - much more readable with the space.
>
> IMHO, 2 should definitely not be fixed, 1.2 could but should not, and that can
> be discussed for 1.1 (avoiding extra spaces seems to be the general asm rule for
> ARM), so that patch could be left unchanged.
>
> What do you think?
Personally, it is more readable if we not fix and we leave the patch
unchanged.
> That would be good to have official ARM asm coding style rules for U-Boot, but
> the coding style used in this patch is also what is used by Linux (e.g. in [1]),
> and Linux is the default reference for U-Boot.
Right. Until a new rule is set, coding style for assembly is what Linux
uses.
Thanks for checking - I will apply the patch as it is.
Best regards,
Stefano Babic
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