[U-Boot] [PATCH 12/12] imx: ventana: switch to SPL

[Tim Harvey]

On Tue, May 6, 2014 at 12:11 PM, Jeroen Hofstee <dasuboot at myspectrum.nl> wrote:
> Hello Tim,
>
> On di, 2014-05-06 at 11:18 -0700, Tim Harvey wrote:
>> On Mon, Apr 28, 2014 at 1:17 PM, Tim Harvey <tharvey at gateworks.com> wrote:
>
>>
>> void board_init_f(ulong dummy)
>> {
>>         struct ventana_board_info ventana_info;
>>         int board_model;
>>
>>         /* Set global data pointer. */
>>         gd = &gdata;
>>
>>         /* setup AIPS and disable watchdog */
>>         arch_cpu_init();
>>
>>         /* iomux and setup of i2c */
>>         board_early_init_f();
>>         i2c_setup_iomux();
>>
>>         /* setup GP timer */
>>         timer_init();
>>
>>         /* UART clocks enabled and gd valid - init serial console */
>>         preloader_console_init();
>>
>>         /* read/validate EEPROM info to determine board model and SDRAM cfg */
>>         board_model = read_eeprom(I2C_GSC, &ventana_info);
>>
>>         /* provide some some default: 32bit 128MB */
>>         if (GW_UNKNOWN == board_model) {
>>                 ventana_info.sdram_width = 2;
>>                 ventana_info.sdram_size = 3;
>>         }
>>
>>         /* configure MMDC for SDRAM width/size and per-model calibration */
>>         spl_dram_init(8 << ventana_info.sdram_width,
>>                       16 << ventana_info.sdram_size,
>>                       board_model);
>>
>>         /* Clear the BSS. */
>>         memset(__bss_start, 0, __bss_end - __bss_start);
>>
>>         /* load/boot image from boot device */
>>         board_init_r(NULL, 0);
>> }
>>
>> Does this make sense?
>
> Since Crt0.S already created gd on the stack before calling
> board_init_f, can't the assignment of gd not simply be removed?
> Is there anything special about gdata?
>
> Regards,
> Jeroen
>
>

Jeroen,

That does make sense, but what I find is that York's ocmmit
dec1861be90c948ea9fb771927d3d26a994d2e20 requires that gd be blanked
and its not. This causes bus_i2c_init to skip its initialization
because p->base is not zero.

York, does this make sense? Your patch creates a dependence on
gd->srdata being blank which isn't the case with the SRAM when booting
from the IMX6 boot rom.

Tim