39.4.3.1 Register Naming
A set of 15 registers is defined and accessible through the use of the load and store architecture.
| Value | Name | Description |
|---|---|---|
| 0 | GFX2D_PA0 | Surface 0 Physical Address Register |
| 1 | GFX2D_PITCH0 | Surface 0 Pitch Register |
| 2 | GFX2D_CFG0 | Surface 0 Configuration Register |
| 3 | GFX2D_PA1 | Surface 1 Physical Address Register |
| 4 | GFX2D_PITCH1 | Surface 1 Pitch Register |
| 5 | GFX2D_CFG1 | Surface 1 Configuration Register |
| 6 | GFX2D_PA2 | Surface 2 Physical Address Register |
| 7 | GFX2D_PITCH2 | Surface 2 Pitch Register |
| 8 | GFX2D_CFG2 | Surface 2 Configuration Register |
| 9 | GFX2D_PA3 | Surface 3 Physical Address Register |
| 10 | GPREG0 | General-Purpose Register 0 |
| 11 | GPREG1 | General-Purpose Register 1 |
| 12 | GPREG2 | General-Purpose Register 2 |
| 13 | GPREG3 | General-Purpose Register 3 |
| 14 | GPREG4 | General-Purpose Register 4 |
| 15 | GPREG5 | General-Purpose Register 5 |
General-purpose registers are generic registers. They can hold:
- an address,
- a constant color for a FILL or BLEND operation,
- a constant alpha value for a BLEND, or
- a user-defined 32-bit data for a STORE operation.
Table 39-27. General-Purpose Registers Operation/Instruction General-Purpose Register FILL The register holds the 32-bit fill color pattern when the FILL arguments are less than 2. In that case, the color is defined by the REG field of the FILL instruction. BLEND The register holds the constant 32-bit color (Ac, Rc, Gc, Bc). It can be used for CONSTANT_ALPHA, CONSTANT_ALPHA parameters. STR The store operation requires a valid address defined by the REGAD field register index, and a data defined by the REG field register index. The general-purpose register can hold a 32-bit address or data. LDR The LDR instruction can load a general-purpose register.