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x1000: fix broken OST2 timer prescaler

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It turns out the prescaler fields in OST_CTRL are 2 bits wide,
not 3. The programming manual (as usual) is ambiguous and its
diagram shows 2-bit wide fields, but the bit positions in the
text give a 3-bit wide field. Ingenic's Linux code and my own
testing shows that they are, in fact, 2 bits wide.

This caused the OST2 divisor to be 16 instead of 4; the OST1
divisor was correct. This means that all udelay/mdelay calls
took 4x longer than they should've. After this change the OST2
prescaler will be 4, as intended, and udelay/mdelay calls will
wait for the intended duration.

Change-Id: I2ac0a9190f49b59a840c649bf586131f5f9fde82
This commit is contained in:
Aidan MacDonald 2021-09-27 17:18:19 +01:00
parent bf54002bc1
commit 7a5130a277
3 changed files with 9 additions and 9 deletions
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4
utils/reggen-ng/x1000.reggen
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@ -807,8 +807,8 @@ node OST {
addr 0xb2000000
reg CTRL 0x00 {
field 5 3 PRESCALE2 { enum BY_1 0; enum BY_4 1; enum BY_16 2; }
field 2 0 PRESCALE1 { enum BY_1 0; enum BY_4 1; enum BY_16 2; }
field 3 2 PRESCALE2 { enum BY_1 0; enum BY_4 1; enum BY_16 2; }
field 1 0 PRESCALE1 { enum BY_1 0; enum BY_4 1; enum BY_16 2; }
}
reg ENABLE 0x04 {