Commit graph

7 commits

Author SHA1 Message Date
David Hendricks
cd14ed71bb [2/3] exynos5: modify thermal management unit code for coreboot
This updates the Exynos TMU code for coreboot:
- Remove dependency on device tree
- Add Makefile entries

Change-Id: I55e1b624d7c7b695b1253ec55f6ae3de8dc671bc
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/3107
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Tested-by: build bot (Jenkins)
2013-04-19 04:19:16 +02:00
David Hendricks
c01d138013 exynos5250: Add function for configuring L2 cache
This adds a new function to configure L2 cache for the
exynos5250 and deprecates the old function.

Change-Id: I9562f3301aa1e2911dae3856ab57bb6beec2e224
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/2949
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Tested-by: build bot (Jenkins)
2013-03-29 22:24:31 +01:00
Ronald G. Minnich
026bbda071 ARM: remove code that is IMHO a dangerous design
OK, this is tl;dr. But I need to write this in hopes we make
sure we don't put code like this into coreboot. Ever.

Our excuse in this case is that it was imported, not obviously wrong,
and easily changed. It made sense to get it in, make it work, then
do a cleanup pass, because changing everything up front is almost
impossible to debug.

The exynos code has bunch of base register values, e.g.

These are base addresses of things that look like a memory-mapped
struct. To get these to a pointer, they created the following macro,
which creates an inline function.

static inline unsigned int samsung_get_base_##device(void)	\
{								\
	return cpu_is_exynos5() ? EXYNOS5_##base : 0;		\
}

And then invoke it 31 times in a .h file, e.g.:
SAMSUNG_BASE(clock, CLOCK_BASE)

to create 31 functions.

And then use it:
        struct exynos5_clock *clk =
	                (struct exynos5_clock *)samsung_get_base_clock();

OK, what's wrong with this? It's easier to ask what's right with it. Answer: nothing.

I have a long list of what's wrong, and I may leave some things out,
but here goes:
1. the "function" can return a NULL if we're not on exynos5. Most uses of the code
   don't check the return value.
2. And why would this function be running, if we're not on an exynos5? Why compile it in?
3. Note the cast everywhere a samsung_get_base_xxx is used.
   The function returns an untyped variable, requiring the *user* to get two
   things right: the cast, and the function invocation. One can replace that _clock(); with
   _power(); in the code above, and they will be referencing the wrong registers, and
   they'll never get an error!
   We have a C compiler; use it to type data.
4. You're generating 31 functions using cpp each and every time the file is included.
   The C compiler has to parse these each time. It's not at all like a simple cpp
   macro which is only generated on use.
5. You can't tags or etags this code
6. In fact, any kind of analysis tool will be unable to do anything with this cpp magic.

That's only a partial list.

So what's the right way to do it? Just make typed constants, viz:

Or, since I expect people will want the lower case function syntax, I've left
it that way:

Now we've got something that is efficient, and we don't even need to protect with
any more.

Hence this change. We've got something that is type checked, does not require users to
cast on each use, will catch simple programming errors, can be analyzed with standard tools,
and builds faster.

So if we make a mistake:
       struct exynos5_clock *clk =
                       samsung_get_base_adc();

We'll see it:
src/cpu/samsung/exynos5250/clock.c: In function 'get_pll_clk':
src/cpu/samsung/exynos5250/clock.c:183:3: error: initialization from incompatible pointer type [-Werror]

which we would not have seen before.

As a minor benefit, it shaves most of a second off the compilation.

Change-Id: Ie67bc4bc038a8dd1837b977d07332d7d7fd6be1f
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-on: http://review.coreboot.org/2582
Tested-by: build bot (Jenkins)
2013-03-04 19:43:19 +01:00
David Hendricks
10883945dc exynos5250: remove CPU check from samsung_get_base_* macro
The cpu_is_exynos5() macro seems broken at the moment, so skip it.
The macro is superfluous and will probably be replaced eventually,
but at least this will un-break usage sites.

Change-Id: Ibd360cbfa18047ad8a3488d4f24c3fc4d7415eba
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/2264
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Tested-by: build bot (Jenkins)
2013-02-03 06:01:44 +01:00
Stefan Reinauer
2f25d9963e ARMv7: drop __ASSEMBLY__
We moved to using __ASSEMBLER__ years ago since it is set by as.

Change-Id: I60103ba23ebe87be1d0bc63beed0ef5b05eed4f2
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/2111
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Tested-by: build bot (Jenkins)
2013-01-05 01:41:14 +01:00
Ronald G. Minnich
23547ddb94 Minor changes to .h files for samsung ARM part
With these changes we have a mostly compiling target.

I'm still removing and pruning .h files, but hopefully later today I'll do
the last few .h commits and move on to .c

Change-Id: Ia82d787496184e028f37d7b67336d61fda75aa94
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Reviewed-on: http://review.coreboot.org/1937
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2012-11-29 00:56:36 +01:00
Ronald G. Minnich
6e3728bb12 Add .h files for samsung exynos 5250
Per a conversation with Stefan, these chip-dependent files are moved
to the src tree, in the manner of other chips (north and southbridge).

Change-Id: I12645ba05eb241eda200ed06cb633541a6a98119
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Signed-off-by: Stefan Reinauer <stepan@coresystems.de>
Reviewed-on: http://review.coreboot.org/1925
Tested-by: build bot (Jenkins)
2012-11-28 07:55:59 +01:00