On 7/17/2019 6:25 PM, Andrey Smirnov wrote:
> In order to be able to unify 64 and 32 bit implementations of
> wr_reg64, let's convert it to use helpers from
> <linux/io-64-nonatomic-hi-lo.h> first. Here are the steps of the
> transformation:
>
> 1. Inline wr_reg32 helpers:
>
> if (!caam_imx && caam_little_end) {
> if (caam_little_end) {
> iowrite32(data >> 32, (u32 __iomem *)(reg) + 1);
> iowrite32(data, (u32 __iomem *)(reg));
> } else {
> iowrite32be(data >> 32, (u32 __iomem *)(reg) + 1);
> iowrite32be(data, (u32 __iomem *)(reg));
> }
> } else {
> if (caam_little_end) {
> iowrite32(data >> 32, (u32 __iomem *)(reg));
> iowrite32(data, (u32 __iomem *)(reg) + 1);
> } else {
> iowrite32be(data >> 32, (u32 __iomem *)(reg));
> iowrite32be(data, (u32 __iomem *)(reg) + 1);
> }
> }
>
> 2. Transfrom the conditionals such that the check for
> 'caam_little_end' is at the top level:
>
> if (caam_little_end) {
> if (!caam_imx) {
> iowrite32(data >> 32, (u32 __iomem *)(reg) + 1);
> iowrite32(data, (u32 __iomem *)(reg));
> } else {
> iowrite32(data >> 32, (u32 __iomem *)(reg));
> iowrite32(data, (u32 __iomem *)(reg) + 1);
> }
> } else {
> iowrite32be(data >> 32, (u32 __iomem *)(reg));
> iowrite32be(data, (u32 __iomem *)(reg) + 1);
> }
>
> 3. Invert the check for !caam_imx:
>
> if (caam_little_end) {
> if (caam_imx) {
> iowrite32(data >> 32, (u32 __iomem *)(reg));
> iowrite32(data, (u32 __iomem *)(reg) + 1);
> } else {
> iowrite32(data >> 32, (u32 __iomem *)(reg) + 1);
> iowrite32(data, (u32 __iomem *)(reg));
> }
> } else {
> iowrite32be(data >> 32, (u32 __iomem *)(reg));
> iowrite32be(data, (u32 __iomem *)(reg) + 1);
> }
>
> 4. Make use of iowrite64* helpers from <linux/io-64-nonatomic-hi-lo.h>
>
> if (caam_little_end) {
> if (caam_imx) {
> iowrite32(data >> 32, (u32 __iomem *)(reg));
> iowrite32(data, (u32 __iomem *)(reg) + 1);
> } else {
> iowrite64(data, reg);
> }
> } else {
> iowrite64be(data, reg);
> }
>
> No functional change intended.
>
> Signed-off-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx>
Reviewed-by: Horia Geantă <horia.geanta@xxxxxxx>
Just to clarify one thing.
For a previous patch I mentioned:
> To be consistent with CAAM engine HW spec: in case of 64-bit registers,
> irrespective of device endianness, the lower address should be read from
> / written to first, followed by the upper address.
https://lore.kernel.org/linux-crypto/VI1PR0401MB259145C2DFDB5E4084EA5DFC98D20@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/
I've checked again and actually there is no limitation wrt. the order in which
the two 32-bit parts of 64-bit registers are read from / written to,
except for performance counters (only available on DN parts, not on i.MX).
However, performance counters do not user {rd,wr}_reg64 and should be fixed
separately.
In conclusion, it's ok to use either hi_lo or lo_hi semantics (which is _data_
semantics btw).
It makes more sense for this patch to include io-64-nonatomic-hi-lo.h since
that's what regs.h currently uses.
Horia
