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dwelch67 / raspberrypi

Raspberry Pi ARM based bare metal examples
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aarch64 gone? #19

Closed BigEd closed 8 years ago

BigEd commented 8 years ago

Did you have some problem with the aarch64 examples for the Pi 3? Maybe I'm looking in the wrong place?

scotws commented 8 years ago

I noticed that too, I'd love to have some Aarch64 examples for the RPi.

dwelch67 commented 8 years ago

sorry everyone they moved under boards/pi3 I am/was trying to deal with N number of boards with anywhere from no differences to many differences between them and up to 4 year old stuff written at the time there was only one board....so still have to work that out...like the other pi1 dirs (blinker01, etc) I should have left aarch64 with a readme...

dwelch67 commented 8 years ago

okay, I dont have much, dont necessarily need much as the C language part doesnt really change you just need a different compiler. the bootstrap assembly changed yes to use the new instruction set.

The leds are behind an i2c gpio expander which I need to find/figure out, you can mailbox your way through the gpu to get there (see the raspberry pi bare metal forum) but I would like to someday figure that out. And of course mmu/interrupts at some point in time...

other than that though it is still a case of once you get into C the instruction set doesnt matter so much.

BigEd commented 8 years ago

Many thanks! (It's a pity in a way that the Pi platform is not a single standard configuration - but on the other hand it is in some ways improving.)

dwelch67 commented 8 years ago

we would still be driving the original model-T or a wright flyer if we didnt have improvements. why move the leds every Nth board? gpio sure, but they didnt add lots more stuff so they didnt need those pins.

I am glad the chips appear to for the most part have the arm core carved out and a new one put in rather than a big do-over each time. eventually that will happen too, they will design around a different chip and maybe we wont get info on it and have to reverse engineer linux sources...

On Wed, Apr 6, 2016 at 3:44 PM, BigEd notifications@github.com wrote:

Many thanks! (It's a pity in a way that the Pi platform is not a single standard configuration - but on the other hand it is in some ways improving.)

— You are receiving this because you commented. Reply to this email directly or view it on GitHub https://github.com/dwelch67/raspberrypi/issues/19#issuecomment-206528764