scottk/OpenCellular
1
0
Fork 0
mirror of https://github.com/Telecominfraproject/OpenCellular.git synced 2025-12-30 18:41:11 +00:00
Code Issues Packages Projects Releases Wiki Activity

reef: Enable PMIC after 3.3V

Browse Source 
This changes the ordering of rail/PMIC init slightly so that the
3.3V rail comes up before the PMIC, which follows the ordering
in the PMIC datasheet for cold booting.

The way we did it earlier was to avoid interrupt storms caused by
powering the SoC's GPIO block with SLP signals before powering the
PMIC. However the PMIC ignores the SLP signals when it's first
enabled, so while the suprious interrupts were visible on the scope
it's unlikely that the software was affected. OTOH, as Kevin pointed
out in CL:358913 enabling the PMIC before the 3.3V causes a race
condition whereby the PMIC may fault.

BUG=chrome-os-partner:51323
BRANCH=none
TEST=built and booted on EVT

Signed-off-by: Rachel Nancollas <rachelsn@chromium.org>
Signed-off-by: David Hendricks <dhendrix@chromium.org>

Change-Id: I6eb734f0600daa5de0d970ce228cf3e7ec97d01d
Reviewed-on: https://chromium-review.googlesource.com/372344
Commit-Ready: David Hendricks <dhendrix@chromium.org>
Tested-by: David Hendricks <dhendrix@chromium.org>
Reviewed-by: Kevin K Wong <kevin.k.wong@intel.com>
Reviewed-by: Shawn N <shawnn@chromium.org>
This commit is contained in:
David Hendricks
2016-08-17 14:20:21 -07:00
committed by chrome-bot
parent 862644b9bb
commit 9342bb62d7
1 changed files with 3 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
board/reef/board.c
View File

@@ -375,14 +375,13 @@ static void chipset_pre_init(void)
* To prevent SLP glitches, PMIC_EN (V5A_EN) should be enabled
* at the same time as PP3300 (chrome-os-partner:51323).
*/
/* Enable PMIC */
gpio_set_level(GPIO_PMIC_EN, 1);
/* Enable 3.3V rail */
gpio_set_level(GPIO_EN_PP3300, 1);
while (!gpio_get_level(GPIO_PP3300_PG))
;
/* Enable PMIC */
gpio_set_level(GPIO_PMIC_EN, 1);
#endif
}
DECLARE_HOOK(HOOK_CHIPSET_PRE_INIT, chipset_pre_init, HOOK_PRIO_DEFAULT);