Building kernel SM-T525 - Galaxy Tab Pro 12.2, 10.1, 8.4 Android Development

Instruction to build a kernel from Samsung Sources:
1. Download and unpack source from http://opensource.samsung.com/reception/receptionSub.do?method=sub&sub=F&searchValue=sm-t525
2. Download and upack android ndk from https://developer.android.com/tools/sdk/ndk/index.html
3. Set enviroment varibles (use gcc 4.6, not 4.8):
export CROSS_COMPILE="~/android/android-ndk-r9d/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86_64/bin/arm-linux-androideabi-"
export ARCH="arm"
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4. If you want to add loadable modules support, apply patch modules_support.patch from attach
patch -p1 < modules_support.patch
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5. Create kernel config
make VARIANT_DEFCONFIG=msm8974_sec_picassoeur_defconfig msm8974_sec_defconfig SELINUX_DEFCONFIG=selinux_defconfig
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6. Buld kernel
make -j3
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7. Buld device tree image
./tools/dtbTool -o dt.img -s 2048 -p ./scripts/dtc/ ./arch/arm/boot/
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8. Buld boot.img (default ramdisk image in attach)
./tools/mkbootimg --kernel ./arch/arm/boot/zImage --ramdisk ramdisk.cpio.gz --cmdline 'console=null androidboot.hardware=qcom user_debug=31 msm_rtb.filter=0x37 ehci-hcd.park=3' --base 0x00000000 --pagesize 2048 --ramdisk_offset 0x02000000 --tags_offset 0x01E00000 --dt dt.img -o boot.img
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9. Create .tar.md5 to flash with Odin
tar -H ustar -c boot.img > boot.tar
md5sum -t boot.tar >> boot.tar
mv boot.tar boot.tar.md5
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10. To fix Wi-Fi edit build.prop on your device, change ro.securestorage.support fron true to false
ro.securestorage.support=false
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GitHub: https://github.com/vanyasvl/android_kernel_samsung_picassoeur

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I'm not a builder, but when wifi doesn't work that usually means a mismatch between kernel and rom.
Sent from my SM-T320 using Tapatalk

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Hello. I'm trying to build stock Samsung kernel for Tab Pro 10.1 Sm-T525 and I have a problem:<br />
Wi-fi isn't working on builded kernel. All kernel configs are default from Samsung, bluetooth and Lte works ok.<br />
<br />
I need help with debug wifi problem.<br />
"ip a" command shows wlan0 network device, but wifi can't be enabled from configuration<br />
<br />
My steps to build kernel:<br />
Download source from http://opensource.samsung.com/reception/receptionSub.do?method=sub&sub=F&searchValue=sm-t525<br />
unpack it to ~/android/kernel<br />
<br />
cd ~/android/kernel<br />
export CROSS_COMPILE="/home/vanyas/android/android-ndk-r9d_x64/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86_64/bin/arm-linux-androideabi-"<br />
export ARCH="arm"<br />
<br />
make VARIANT_DEFCONFIG=msm8974_sec_picassoeur_defconfig msm8974_sec_defconfig SELINUX_DEFCONFIG=selinux_defconfig<br />
make -j3<br />
<br />
./tools/dtbTool -o dt.img -s 2048 -p ./scripts/dtc/ ./arch/arm/boot/<br />
<br />
unpack original boot.img with split_boot to boot folder<br />
<br />
./tools/mkbootimg --kernel ./arch/arm/boot/zImage --ramdisk boot/boot.img-ramdisk.cpio.gz --cmdline 'console=null androidboot.hardware=qcom user_debug=31 msm_rtb.filter=0x37 ehci-hcd.park=3' --base 0x00000000 --pagesize 2048 --ramdisk_offset 0x02000000 --tags_offset 0x01E00000 --dt dt.img -o boot.img<br />
<br />
tar -H ustar -c boot.img > boot.tar<br />
md5sum -t boot.tar >> boot.tar<br />
mv boot.tar boot.tar.md5
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For the sm-t320, the kernel is built with version checks on the modules. This is what I did to allow the wlan module to load:
https://github.com/crpalmer/android...mmit/76275b29746dfeab37efeab6c2787af9acd3394c
You'd obviously need to specify the right version string (it should be in the output of dmesg if this is why your wlan isn't working).
Also, if you plan on sharing the kernel, you should zip the .tar.md5 file as I had problems with it failing to flash after downloading when I released just a .tar.md5.

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crpalmer said:
For the sm-t320, the kernel is built with version checks on the modules. This is what I did to allow the wlan module to load:
https://github.com/crpalmer/android...mmit/76275b29746dfeab37efeab6c2787af9acd3394c
You'd obviously need to specify the right version string (it should be in the output of dmesg if this is why your wlan isn't working).
Also, if you plan on sharing the kernel, you should zip the .tar.md5 file as I had problems with it failing to flash after downloading when I released just a .tar.md5.
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Thanks, but it is not a module load problem. SM-T525 kernel builds without modules support and wifi driver (bcm4339) compilled into the kernel.

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vanyas said:
Thanks, but it is not a module load problem. SM-T525 kernel builds without modules support and wifi driver (bcm4339) compilled into the kernel.
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That's interesting. The sm-t320 is a prima chipset which is built as a module.
Do you see anything in the logcat or the dmesg related to the wlan, bcm4339, wifi, etc?

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There are patches for SM-T525 kernel source that resolve problem with "modules support" compilation
--- kernel_orig/arch/arm/mm/proc-syms.c 2014-04-09 12:10:04.846114000 +1100
+++ kernel/arch/arm/mm/proc-syms.c 2014-04-09 11:54:33.894114000 +1100
@@ -18,7 +18,6 @@
#ifndef MULTI_CPU
EXPORT_SYMBOL(cpu_dcache_clean_area);
EXPORT_SYMBOL(cpu_set_pte_ext);
-EXPORT_SYMBOL(cpu_tima_set_pte_ext);
#else
EXPORT_SYMBOL(processor);
#endif
--- kernel_orig/arch/arm/mach-msm/sec-switch.c 2014-01-23 15:34:20.000000000 +1100
+++ kernel/arch/arm/mach-msm/sec-switch.c 2014-04-09 11:29:26.322114000 +1100
@@ -2565,7 +2565,7 @@
pr_info("%s: Ignore Cable setting, Not LPM mode\n", __func__);
}
}
-EXPORT_SYMBOL(fsa9485_set_mhl_cable)
+EXPORT_SYMBOL(fsa9485_set_mhl_cable);
boon fsa9485_muic_is_mhl_attached(void)
{
--- kernel_orig/Makefile 2014-01-23 15:34:19.000000000 +1100
+++ kernel/Makefile 2014-04-09 20:55:48.278114000 +1100
@@ -351,7 +351,7 @@
CHECKFLAGS := -D__linux__ -Dlinux -D__STDC__ -Dunix -D__unix__ \
-Wbitwise -Wno-return-void $(CF)
-CFLAGS_MODULE =
+CFLAGS_MODULE = -fno-pic
AFLAGS_MODULE =
LDFLAGS_MODULE =
CFLAGS_KERNEL =
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Yes! I did it!
To fix wifi: ro.securestorage.support=false in build.prop

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thornev said:
I'm not a builder, but when wifi doesn't work that usually means a mismatch between kernel and rom.
Sent from my SM-T320 using Tapatalk
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I am a builder and what he said is correct.
Samsung did some crazy stuff with Knox.

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scrosler said:
I am a builder and what he said is correct.
Samsung did some crazy stuff with Knox.
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can you make a thread showing us some the difficulties you encountered working around Knox?
Silkmeister

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@Silkmeister1, @Scott, @vanyas, @crpalmer:
I do have a WiFi/BT issue with my (second hand) device. Wifi/BT is not to be enabled in Android. My first suspect was a broken connection, but couldn't found something obvious.
I tried to update Stock Rom and found and issue with ODIN. Stock Rom was not installable, returns with size error in hidden image. (??? what is in there ???). Installed latest LOS and checked the boot messages.
Do you think this can be a software issue? Is there anything missing (stuff in hidden partition) ?
Code:
failed to power up wifi chip, retry again (4 left) **
[ 4.035535] ## wifi_remove
[ 4.035538] wifi_set_power = 0
[ 4.035541] ------------------------------------------------
[ 4.035542] ------------------------------------------------
[ 4.035544] brcm_wlan_power Enter: power off
[ 4.035548] WL_REG_ON off-step : [1]
[ 4.035554] WL_REG_ON off-step-2 : [0]
[ 4.139482] wifi_set_carddetect = 0
[ 4.139485] brcm_wifi_status:359 status 0
[ 4.139487] mmc0: Slot status change detected (1 -> 0)
[ 4.139870] wifi_set_power = 1
[ 4.139873] ------------------------------------------------
[ 4.139874] ------------------------------------------------
[ 4.139876] brcm_wlan_power Enter: power on
[ 4.139880] WL_REG_ON on-step : [0]
[ 4.139887] WL_REG_ON on-step-2 : [1]
[ 4.349477] wifi_set_carddetect = 1
[ 4.349480] brcm_wifi_status:359 status 1
…
Complete bootlog can be seen here in the attachment:
https://forum.xda-developers.com/showpost.php?p=72624259&postcount=213
Any help is welcome!