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| author | Joe Komlodi | 2022-06-13 14:05:48 +0200 |
|---|---|---|
| committer | Cédric Le Goater | 2022-06-22 09:49:34 +0200 |
| commit | 4a71d6d32e59ecf02c246037198882e59894db3d (patch) | |
| tree | 088227f509142b907230cfb7aa2bbf8e83704e74 /include | |
| parent | test/avocado/machine_aspeed.py: Add an I2C RTC test (diff) | |
| download | qemu-4a71d6d32e59ecf02c246037198882e59894db3d.tar.gz qemu-4a71d6d32e59ecf02c246037198882e59894db3d.tar.xz qemu-4a71d6d32e59ecf02c246037198882e59894db3d.zip | |
hw/registerfields: Add shared fields macros
Occasionally a peripheral will have different operating modes, where the
MMIO layout changes, but some of the register fields have the same offsets
and behaviors.
To help support this, we add SHARED_FIELD_XX macros that create SHIFT,
LENGTH, and MASK macros for the fields that are shared across registers,
and accessors for these fields.
An example use may look as follows:
There is a peripheral with registers REG_MODE1 and REG_MODE2 at
different addreses, and both have a field FIELD1 initialized by
SHARED_FIELD().
Depending on what mode the peripheral is operating in, the user could
extract FIELD1 via
SHARED_ARRAY_FIELD_EX32(s->regs, R_REG_MODE1, FIELD1)
or
SHARED_ARRAY_FIELD_EX32(s->regs, R_REG_MODE2, FIELD1)
Signed-off-by: Joe Komlodi <komlodi@google.com>
Change-Id: Id3dc53e7d2f8741c95697cbae69a81bb699fa3cb
Message-Id: <20220331043248.2237838-2-komlodi@google.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/hw/registerfields.h | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/include/hw/registerfields.h b/include/hw/registerfields.h index 3a88e135d0..1330ca77de 100644 --- a/include/hw/registerfields.h +++ b/include/hw/registerfields.h @@ -154,4 +154,74 @@ #define ARRAY_FIELD_DP64(regs, reg, field, val) \ (regs)[R_ ## reg] = FIELD_DP64((regs)[R_ ## reg], reg, field, val); + +/* + * These macros can be used for defining and extracting fields that have the + * same bit position across multiple registers. + */ + +/* Define shared SHIFT, LENGTH, and MASK constants */ +#define SHARED_FIELD(name, shift, length) \ + enum { name ## _ ## SHIFT = (shift)}; \ + enum { name ## _ ## LENGTH = (length)}; \ + enum { name ## _ ## MASK = MAKE_64BIT_MASK(shift, length)}; + +/* Extract a shared field */ +#define SHARED_FIELD_EX8(storage, field) \ + extract8((storage), field ## _SHIFT, field ## _LENGTH) + +#define SHARED_FIELD_EX16(storage, field) \ + extract16((storage), field ## _SHIFT, field ## _LENGTH) + +#define SHARED_FIELD_EX32(storage, field) \ + extract32((storage), field ## _SHIFT, field ## _LENGTH) + +#define SHARED_FIELD_EX64(storage, field) \ + extract64((storage), field ## _SHIFT, field ## _LENGTH) + +/* Extract a shared field from a register array */ +#define SHARED_ARRAY_FIELD_EX32(regs, offset, field) \ + SHARED_FIELD_EX32((regs)[(offset)], field) +#define SHARED_ARRAY_FIELD_EX64(regs, offset, field) \ + SHARED_FIELD_EX64((regs)[(offset)], field) + +/* Deposit a shared field */ +#define SHARED_FIELD_DP8(storage, field, val) ({ \ + struct { \ + unsigned int v:field ## _LENGTH; \ + } _v = { .v = val }; \ + uint8_t _d; \ + _d = deposit32((storage), field ## _SHIFT, field ## _LENGTH, _v.v); \ + _d; }) + +#define SHARED_FIELD_DP16(storage, field, val) ({ \ + struct { \ + unsigned int v:field ## _LENGTH; \ + } _v = { .v = val }; \ + uint16_t _d; \ + _d = deposit32((storage), field ## _SHIFT, field ## _LENGTH, _v.v); \ + _d; }) + +#define SHARED_FIELD_DP32(storage, field, val) ({ \ + struct { \ + unsigned int v:field ## _LENGTH; \ + } _v = { .v = val }; \ + uint32_t _d; \ + _d = deposit32((storage), field ## _SHIFT, field ## _LENGTH, _v.v); \ + _d; }) + +#define SHARED_FIELD_DP64(storage, field, val) ({ \ + struct { \ + uint64_t v:field ## _LENGTH; \ + } _v = { .v = val }; \ + uint64_t _d; \ + _d = deposit64((storage), field ## _SHIFT, field ## _LENGTH, _v.v); \ + _d; }) + +/* Deposit a shared field to a register array */ +#define SHARED_ARRAY_FIELD_DP32(regs, offset, field, val) \ + (regs)[(offset)] = SHARED_FIELD_DP32((regs)[(offset)], field, val); +#define SHARED_ARRAY_FIELD_DP64(regs, offset, field, val) \ + (regs)[(offset)] = SHARED_FIELD_DP64((regs)[(offset)], field, val); + #endif |