On 07/03/2018 04:07 AM, Heinrich Schuchardt wrote:
On 07/03/2018 01:51 AM, Takahiro AKASHI wrote:
On Mon, Jul 02, 2018 at 07:07:55PM +0300, Tuomas Tynkkynen wrote:
Hi Heinrich,
On 06/29/2018 01:34 AM, Heinrich Schuchardt wrote:
QEMU provides an emulated ARM AMBA PrimeCell PL031 RTC.
The patch sets the base address in the board include file according to the definition in hw/arm/virt.c of the QEMU source. It defines the Kconfig option for the existing driver, and enables the RTC driver in qemu_arm64_defconfig and qemu_arm_defconfig as well as the date command.
We need an RTC to provide the GetTime() runtime service in the UEFI subsystem.
Signed-off-by: Heinrich Schuchardt xypron.glpk@gmx.de
configs/qemu_arm64_defconfig | 2 ++ configs/qemu_arm_defconfig | 2 ++ drivers/rtc/Kconfig | 7 +++++++ include/configs/qemu-arm.h | 3 +++ 4 files changed, 14 insertions(+)
Reviewed-by: Tuomas Tynkkynen tuomas.tynkkynen@iki.fi Tested-by: Tuomas Tynkkynen tuomas.tynkkynen@iki.fi
- Tuomas
Well, it is a good time. Why not change the driver to driver model like below:
- I intentionally leave CONFIG_DM_RTC not mandatory here
- The patch may be split into two parts; one for rtc, the other for qemu-arm
Hello Takahiro,
thank you for your suggestion. Yes we should convert drivers to the driver model. Unfortunately the patch that you appended below is not applicable to u-boot/master.
Error: patch failed: include/configs/qemu-arm.h:36 error: include/configs/qemu-arm.h: patch does not apply Patch failed at 0001 ARM: qemu-arm: enable RTC
So I copied the changes to qemu-arm.h manually. Instead of defining the base address here it would be preferable to read the address from the device tree. This will become important if we get
Compiling with CONFIG_DM_RTC and CONFIG_RTC_PL031 resulted in warnings:
CC drivers/rtc/pl031.o drivers/rtc/pl031.c: In function ‘pl031_rtc_set’: drivers/rtc/pl031.c:141:17: warning: passing argument 1 of ‘rtc_set’ discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers] return rtc_set(tm); ^~ drivers/rtc/pl031.c:72:5: note: expected ‘struct rtc_time *’ but argument is of type ‘const struct rtc_time *’ int rtc_set(struct rtc_time *tmp) ^~~~~~~
I tested both with qemu-arm64_defconfig and qemu-arm_defconfig. The date command is running fine in both cases.
The driver with your patch cannot be compiled without DM_RTC (due to missing symbol CONFIG_SYS_RTC_PL031_BASE) so in Kconfig it should depend on DM_RTC.
There is no need to keep any old style stuff. I suggest to drop legacy functions and #ifdef CONFIG_DM_RTC. Also the following line can be removed:
scripts/config_whitelist.txt:4118:CONFIG_SYS_RTC_PL031_BASE
In qemu/hw/arm/virt.c, function create_rtc() a device tree node is created which describes the pl031 RTC including the base address. From what I read in the code the node should look like this:
/{
pl011@09010000 { compatible = "arm,pl011", "arm,primecell"; #address-cells = <2>; #size-cells = <2>; reg = reg = <0x09010000 0x00001000>; ... };
};
You can print the actual device tree within U-Boot using:
fdt addr ${fdtcontroladdr} fdt print /
This is the relevant part of the output:
/ { interrupt-parent = <0x00008001>; #size-cells = <0x00000002>; #address-cells = <0x00000002>; compatible = "linux,dummy-virt";
pl031@9010000 { clock-names = "apb_pclk"; clocks = <0x00008000>; interrupts = <0x00000000 0x00000002 0x00000004>; reg = <0x00000000 0x09010000 0x00000000 0x00001000>; compatible = "arm,pl031", "arm,primecell"; };
};
Regards
Heinrich