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path: root/drivers/timer/tsc_timer.c
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2019-02-12x86: tsc: Add support for native calibration of TSC freqBernhard Messerklinger
Add native tsc calibration function. Calibrate the tsc timer the same way as linux does in arch/x86/kernel/tsc.c. Fixes booting for Apollo Lake processors. Signed-off-by: Bernhard Messerklinger <bernhard.messerklinger@br-automation.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2018-11-14timer: Remove DM_FLAG_PRE_RELOC flag in various driversBin Meng
When a driver declares DM_FLAG_PRE_RELOC flag, it wishes to be bound before relocation. However due to a bug in the DM core, the flag only takes effect when devices are statically declared via U_BOOT_DEVICE(). This bug has been fixed recently by commit "dm: core: Respect drivers with the DM_FLAG_PRE_RELOC flag in lists_bind_fdt()", but with the fix, it has a side effect that all existing drivers that declared DM_FLAG_PRE_RELOC flag will be bound before relocation now. This may expose potential boot failure on some boards due to insufficient memory during the pre-relocation stage. To mitigate this potential impact, the following changes are implemented: - Remove DM_FLAG_PRE_RELOC flag in the driver, if the driver only supports configuration from device tree (OF_CONTROL) - Keep DM_FLAG_PRE_RELOC flag in the driver only if the device is statically declared via U_BOOT_DEVICE() - Surround DM_FLAG_PRE_RELOC flag with OF_CONTROL check, for drivers that support both statically declared devices and configuration from device tree Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org>
2018-10-22x86: tsc: Introduce config option for early timer frequencyBin Meng
So far the TSC timer driver supports trying hardware calibration first and using device tree as last resort for its running frequency as the normal timer. However when it is used as the early timer, it only supports hardware calibration and if it fails, the driver just panics. This introduces a new config option to specify the early timer frequency in MHz and it should be equal to the value described in the device tree. Without this patch, the travis-ci testing on QEMU x86_64 target fails each time after it finishes the 'bootefi selftest' as the test.py see an error was emitted on the console like this: TSC frequency is ZERO resetting ... ### ERROR ### Please RESET the board ### It's strange that this error is consistently seen on the travis-ci machine, but only occasionally seen on my local machine (maybe 1 out of 10). Since QEMU x86_64 target enables BOOTSTAGE support which uses early timer, with this fix it should work without any failure. Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org>
2018-08-20x86: tsc: Try hardware calibration firstBin Meng
At present if TSC frequency is provided in the device tree, it takes precedence over hardware calibration result. This swaps the order to try hardware calibration first and uses device tree as last resort. This can be helpful when a generic dts (eg: coreboot/efi payload) is supposed to work on as many hardware as possible, including emulators like QEMU where TSC hardware calibration sometimes fails. Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
2018-07-02x86: timer: tsc: Allow specifying clock rate from device tree againBin Meng
With the introduction of early timer support in the TSC driver, the capability of getting clock rate from device tree was lost unfortunately. Now we bring such functionality back, but with a limitation that when TSC is used as early timer, specifying clock rate from device tree does not work. This fixes random boot failures seen on QEMU targets: printing "TSC frequency is ZERO" and reset forever. Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org>
2018-06-13x86: tsc: add support for reading CPU freq from cpuidChristian Gmeiner
Starting with cpuid level 0x16 (Skylake-based processors) it is possible to get CPU base freq via cpuid. This fixes booting on a skylake based system. Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com> Reviewed-by: Bin Meng <bmeng.cn@gmail.com> [bmeng: fixed wrong indention of labels] Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
2018-05-07SPDX: Convert all of our single license tags to Linux Kernel styleTom Rini
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>
2017-09-16dm: x86: Allow TSC timer to be used before DM is readySimon Glass
With bootstage we need access to the timer before driver model is set up. To handle this, put the required state in global_data and provide a new function to set up the device, separate from the driver's probe() method. This will be used by the 'early' timer also. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2017-09-16x86: tsc: Add Airmont reference clock valuesBin Meng
Per the Intel 64 and IA-32 Architecture Software Developer's Manual, add the reference clock for Intel Atom Processors based on the Airmont Microarchitecture (Braswell). This keeps in sync with Linux kernel commit: 6fcb41c: x86/tsc_msr: Add Airmont reference clock values Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org>
2017-08-01x86: tsc: Rename try_msr_calibrate_tsc() to cpu_mhz_from_msr()Bin Meng
Rename try_msr_calibrate_tsc() to cpu_mhz_from_msr(), as that better describes what the routine does. This keeps in sync with Linux kernel commit: 02c0cd2: x86/tsc_msr: Remove irqoff around MSR-based TSC enumeration Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org>
2017-08-01x86: tsc: Correct Silvermont reference clock valuesBin Meng
Atom processors use a 19.2 MHz crystal oscillator. Early processors generate 100 MHz via 19.2 MHz * 26 / 5 = 99.84 MHz. Later processors generate 100 MHz via 19.2 MHz * 125 / 24 = 100 MHz. Update the Silvermont-based tables accordingly, matching the Software Developers Manual. Also, correct a 166 MHz entry that should have been 116 MHz, and add a missing 80 MHz entry for VLV2. This keeps in sync with Linux kernel commit: 05680e7: x86/tsc_msr: Correct Silvermont reference clock values Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org>
2017-08-01x86: tsc: Update comments and expand definitions in freq_desc_tables[]Bin Meng
Some processor abbreviations in the comments of freq_desc_tables[] are obscure. This updates part of these to mention processors that are known to us. Also expand frequency definitions. This keeps in sync with Linux kernel commit: 9e0cae9: x86/tsc_msr: Update comments, expand definitions Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org>
2017-08-01x86: tsc: Remove the fail handling in try_msr_calibrate_tsc()Bin Meng
If either ratio or freq is zero, the return value is zero. There is no need to create a fail branch and return zero there. This keeps in sync with Linux kernel commit: 14bb4e3: x86/tsc_msr: Remove debugging messages Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org>
2017-08-01x86: tsc: Identify Intel-specific codeBin Meng
try_msr_calibrate_tsc() is currently Intel-specific, and should not execute on any other vendor's parts. This keeps in sync with Linux kernel commit: ba82683: x86/tsc_msr: Identify Intel-specific code Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org>
2017-08-01x86: tsc: Read all ratio bits from MSR_PLATFORM_INFOBin Meng
Currently we read the tsc radio like this: ratio = (MSR_PLATFORM_INFO >> 8) & 0x1f; Thus we get bit 8-12 of MSR_PLATFORM_INFO, however according to the Intel manual, the ratio bits are bit 8-15. Fix this problem by masking 0xff instead. This keeps in sync with Linux kernel commit: 886123f: x86/tsc: Read all ratio bits from MSR_PLATFORM_INFO Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Reviewed-by: Simon Glass <sjg@chromium.org>
2015-12-09x86: Move i8254_init() to x86_cpu_init_f()Bin Meng
Right now i8254_init() is called from timer_init() in the tsc timer driver. But actually i8254 and tsc are completely different things. Since tsc timer has been converted to driver model, we should find a new place that is appropriate for U-Boot to call i8254_init(), which is now x86_cpu_init_f(). Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Acked-by: Simon Glass <sjg@chromium.org>
2015-12-01x86: tsc: Move tsc_timer.c to drivers/timerBin Meng
To group all dm timer drivers together, move tsc timer to drivers/timer directory. Signed-off-by: Bin Meng <bmeng.cn@gmail.com> Acked-by: Simon Glass <sjg@chromium.org>