Commit graph

11 commits

Author SHA1 Message Date
Stephan Gerhold
0204d1b56b board: dragonboard410c: Load U-Boot directly without LK
At the moment the U-Boot port for the DragonBoard 410c is designed
to be loaded as an Android boot image after Qualcomm's Little Kernel (LK)
bootloader. This is simple to set up but LK is redundant in this case,
since everything done by LK can be also done directly by U-Boot.

Dropping LK entirely has at least the following advantages:
  - Easier installation/board code (no need for Android boot images)
  - (Slightly) faster boot
  - Boot directly in 64-bit without a round trip to 32-bit for LK

So far this was not possible yet because of unsolved problems:

  1. Signing tool: The firmware expects a "signed" ELF image with extra
     (Qualcomm-specific) ELF headers, usually used for secure boot.
     The DragonBoard 410c does not have secure boot by default but the
     extra ELF headers are still required.

  2. PSCI bug: There seems to be a bug in the PSCI implementation
     (part of the TrustZone/tz firmware) that causes all other CPU cores
     to be started in 32-bit mode if LK is missing in the boot chain.
     This causes Linux to hang early during boot.

There is a solution for both problems now:

  1. qtestsign (https://github.com/msm8916-mainline/qtestsign)
     can be used as a "signing" tool for U-Boot and other firmware.

  2. A workaround for the "PSCI bug" is to execute the TZ syscall when
     entering U-Boot. That way PSCI is made aware of the 64-bit switch
     and starts all other CPU cores in 64-bit mode as well.

Simplify the dragonboard410c board by removing all the extra code that
is only used to build an Android boot image that can be loaded by LK.
This allows dropping the custom linker script, special image magic,
as well as most of the special build/installation instructions.

CONFIG_REMAKE_ELF is used to build a new ELF image that has both U-Boot
and the appended DTB combined. The resulting u-boot.elf can then be
passed to the "signing" tool (e.g. qtestsign).

The PSCI workaround is placed in the "boot0" hook that is enabled
with CONFIG_ENABLE_ARM_SOC_BOOT0_HOOK. The extra check for EL1 allows
compatibility with custom firmware that enters U-Boot in EL2 or EL3,
e.g. qhypstub (https://github.com/msm8916-mainline/qhypstub).

As a first step these changes apply only to DragonBoard410c.
Similar changes could likely also work for the DragonBoard 820c.

Note that removing LK wouldn't be possible that easily without a lot of
work already done three years ago by Ramon Fried. A lot of missing
initialization, pinctrl etc was already added back then even though
it was not strictly needed yet.

Cc: Ramon Fried <rfried.dev@gmail.com>
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
2021-07-23 18:53:45 -04:00
Sheep Sun
9b6b25c635 arm: snapdragon: Use correct GICC register on APQ8016
The GICC register used by u-boot is 0x0a20c000, which is actually a GICC
for WCNSS, the WLAN processor. U-boot runs on the Application Processor,
therefore it should use APCS GICC instead. Hence, correct it with APCS GICC
register address.

Signed-off-by: Sheep Sun <sunxiaoyang2003@gmail.com>
2021-07-06 14:12:15 -04:00
Ramon Fried
604aa9d30b arm: mach-snapdragon: db820c: Actually init PLL for serial
The PLL for the UART was not set, and relied on previous
initializtion made by LK. add the appropriate initialization.

Signed-off-by: Ramon Fried <ramon.fried@gmail.com>
2019-01-25 12:12:55 -05:00
Ramon Fried
e0b04a1525 snapdragon: added MAC generation functions
Add support for generation of unique MAC address
that is derived from board serial.
Algorithm for generation of MAC taken from LK.

Signed-off-by: Ramon Fried <ramon.fried@gmail.com>
2018-08-13 14:04:04 -04:00
Ramon Fried
86e5e42946 snapdragon: added msm_board_serial() func
This commit adds a function to get the board
serial number.
In snapdragon it's actually the eMMC serial number.

Function added in a new file misc.c that will
include further snapdragon miscellaneous functions.

Signed-off-by: Ramon Fried <ramon.fried@gmail.com>
2018-08-13 14:04:04 -04:00
Ramon Fried
36adb7c9e8 snapdragon: Add DRAM detection & FDT fixup
Fixup the Linux FDT with the detection of onboard DRAM as
provided by SBL (Secondary boot loader) by reading
the shared-memory region.

Signed-off-by: Ramon Fried <ramon.fried@gmail.com>
2018-08-10 13:45:35 -04:00
Ramon Fried
640dc34942 mach-snapdragon: Fix UART clock flow
UART clock enabling flow was wrong.
Changed the flow according to downstream implementation in LK.

Signed-off-by: Ramon Fried <ramon.fried@gmail.com>
2018-05-26 18:19:11 -04:00
Tom Rini
83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00
Jorge Ramirez-Ortiz
4b684a6b82 db820c: add qualcomm dragonboard 820C support
This commit adds support for 96Boards Dragonboard820C.

The board is based on APQ8086 Qualcomm Soc, complying with the
96Boards specification.

Features
 - 4x Kyro CPU (64 bit) up to 2.15GHz
 - USB2.0
 - USB3.0
 - ISP
 - Qualcomm Hexagon DSP
 - SD 3.0 (UHS-I)
 - UFS 2.0
 - Qualcomm Adreno 530 GPU
 - GPS
 - BT 4.2
 - Wi-Fi 2.4GHz, 5GHz (802.11ac)
 - PCIe 2.0
 - MIPI-CSI, MIPI-DSI
 - I2S

U-Boot boots chained from LK (LK implements the fastboot protocol) in
64-bit mode.

For detailed build instructions see readme.txt in the board directory.

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
2018-01-15 16:29:02 -05:00
Jorge Ramirez-Ortiz
7c75f7f1b2 arm: mach-snapdragon: refactor clock driver
In preparation to add support for the Dragonboard820c (APQ8096),
refactor the current Snapdragon clock driver.

No new functionality has been added.

Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>
2018-01-15 16:29:02 -05:00
Mateusz Kulikowski
085921368b arm: Add support for Qualcomm Snapdragon family
First supported chip is APQ8016 (that is compatible with MSM8916).
Drivers in SoC code:
- Reset controller (PSHOLD)
- Clock controller (very simple clock configuration for MMC and UART)

Signed-off-by: Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
2016-04-01 17:18:26 -04:00