Hi Sascha, On 28.02.24 12:05, Sascha Hauer wrote: > On Wed, Feb 28, 2024 at 09:46:51AM +0100, Stefan Kerkmann wrote: >> Hi Sascha, >> >> On 27.02.24 09:44, Sascha Hauer wrote: >>> On Mon, Feb 26, 2024 at 03:40:23PM +0100, Stefan Kerkmann wrote: >>>> Instead of passing in configuration parameters at runtime we can utilize >>>> the `cpu_is_mx8xyz` macro family to determine which bits should be set. >>>> >>>> As the tzasc driver is imx specific, all functions are prefixed with >>>> `imx8m_` as well. >>>> >>>> Signed-off-by: Stefan Kerkmann <s.kerkmann@xxxxxxxxxxxxxx> >>>> --- >>>> arch/arm/mach-imx/atf.c | 8 ++++---- >>>> arch/arm/mach-imx/imx8m.c | 2 +- >>>> arch/arm/mach-imx/tzasc.c | 25 +++++-------------------- >>>> include/mach/imx/tzasc.h | 8 ++------ >>>> 4 files changed, 12 insertions(+), 31 deletions(-) >>>> >>>> diff --git a/arch/arm/mach-imx/atf.c b/arch/arm/mach-imx/atf.c >>>> index e8060ebd95..9cbc38ef11 100644 >>>> --- a/arch/arm/mach-imx/atf.c >>>> +++ b/arch/arm/mach-imx/atf.c >>>> @@ -158,7 +158,7 @@ __noreturn void __imx8mm_load_and_start_image_via_tfa(void *bl33) >>>> size_t bl32_size; >>>> void *bl32_image; >>>> - imx8mm_tzc380_init(); >>>> + imx8m_tzc380_init(); >>> >>> I am not so sure about this patch. So far the whole PBL is coded in the >>> way that we inherently know the SoC type from the code path chosen. >>> >>> This patch changes this. It doesn't really matter for this patch, but it >>> sends a sign how we want to solve this in future. >> >> Let's see if I can persuade you that this is a good thing :-). >> >>> One implication of this patch is that cpu_is_mx() is a runtime decision, >>> so code paths behind an unused cpu_is_mx() can't be discarded anymore. >> >> My argument here is that the overhead in code size is probably neglect able >> in most cases, as most of the code paths are still discarded: >> >> 1. If there is only one ARCH selected e.g., `CONFIG_ARCH_IMX8MM` the >> `cpu_is_mx8mm()` macro is still evaluated at compile time. As the >> `__imx_cpu_type` variable is only assigned and never read it can be stripped >> away by the compiler/linker and become a nop. >> >> 2. Runtime evaluation is only selected if a second arch is enabled for the >> build. But even then the runtime decision is only compiled in for the two >> selected arches, as all other `cpu_is_xyz` macros still evaluate at compile >> time to false. So code paths that don't touch the selected arches will still >> be stripped. >> >>> Another thing is that the usage of cpu_is() has the tendency to lead to >>> cascades of if (cpu_is_x() || cpu_is_y() || cpu_is_z()) which is not >>> paticularly nice to read. >>> >> >> That is arguably subjective :-). >> >> For me as a developer that is new to barebox, it was confusing to find two >> different styles of arch dependent code. I prefer the `cpu_is_xyz` style >> approach which is used in barebox proper much more. >> >> In the case of the TZC380 driver the pseudo (as they are probably optimized >> away) runtime arguments to the init functions seem unnecessarily >> complicated, as does the approach to define aliases to the same function for >> all arches. The if style is clearer in intend as it keeps the distinction >> between the arches local to the parts that are actually different. Which is >> straight forward to read IMHO. > > Ok, let's see where this brings us. Can you rebase on current next? > Some of the code you are modifying went to drivers/soc/imx/soc-imx8m.c > recently. > Great :-)! I've rebased and sent a v2 of this patch set. > Sascha > Cheers, Stefan -- Pengutronix e.K. | Stefan Kerkmann | Steuerwalder Str. 21 | https://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-128 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-9 |
