Currently there is one DRAM parameter struct for the Allwinner H616 DRAM
"driver". It contains many fields that are compile time constants
(set by Kconfig variables), though there are also some fields that are
probed and changed over the runtime of the DRAM initialisation.
Because of this mixture, the compiler cannot properly optimise the code
for size, as it does not consider constant propagation in its full
potential.
Help the compiler out by splitting that structure into two: one that only
contains values known at compile time, and another one where the values
will actually change. The former can then be declared "const", which will
let the compiler fold its values directly into the code using it.
We also add "const" tags for some new "struct dram_config" pointers, to
further increase code optimisation.
To help the compiler optimise the code further, the definition of the
now "const struct dram_para" has to happen at a file-global level, so
move that part out of sunxi_dram_init().
That results in quite some code savings (almost 2KB), and helps to keep
the code small with the LPDDR3 support added later.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
There are quite some functions in the Allwinner H616 DRAM "driver", some
of them actually change the parameters in the structure passed to them,
but many are actually not.
To increase the optimisation potential for the code, mark those functions
that just read members of the passed dram_para struct as "const".
This in itself does not decrease the code size, but lays the groundwork
for future changes doing so.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
It turns out that some H616 and related SoCs (like H313) need TPR2
parameter for proper working. Add it.
Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Part of the code, previously known as "unknown feature", also doesn't
have constant values. They are derived from TPR0 parameter in vendor
DRAM code.
Let's move that code to separate function and introduce TPR0 parameter
here too, to ease adding new boards.
Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
These values are highly board specific and thus make sense to add
parameter for them. To ease adding support for new boards, let's make
them same as in vendor DRAM settings.
Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Vendor DRAM settings use TPR10 parameter to enable various features.
There are many mores features that just those that are currently
mentioned. Since new will be added later and most are not known, let's
reuse value from vendor DRAM driver as-is. This will also help adding
support for new boards.
Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
While ODT values for same memory type are similar, they are not
necessary the same. Let's parameterize them and make parameter same as
in vendor DRAM settings. That way it will be easy to introduce new board
support.
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Allwinner H616 supports many types of DRAM. Most notably it supports
LPDDR4. However, all commercially available boards at this time use
only DDR3, so this commit adds only DDR3 support.
Controller and MBUS are very similar to H6 but PHY is completely
unknown.
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Acked-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
