ArmPlatformPkg: PL061 - rewrite the hardware interaction

The PL061 GPIO controller is a bit of an anachronism, and the existing
driver does nothing to hide this - leading to it being very tricky to
read.

Rewrite it to document (in comments and code) what is actually
happening, and fix some bugs in the process.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Ryan Harkin <ryan.harkin@linaro.org>
This commit is contained in:
Leif Lindholm
2015-10-28 18:11:49 +00:00
parent 41501f18fd
commit 328d8cfa62
2 changed files with 62 additions and 15 deletions

View File

@@ -19,6 +19,7 @@
#include <Protocol/EmbeddedGpio.h>
// PL061 GPIO Registers
#define PL061_GPIO_DATA_REG_OFFSET ((UINTN) 0x000)
#define PL061_GPIO_DATA_REG ((UINT32)PcdGet32 (PcdPL061GpioBase) + 0x000)
#define PL061_GPIO_DIR_REG ((UINT32)PcdGet32 (PcdPL061GpioBase) + 0x400)
#define PL061_GPIO_IS_REG ((UINT32)PcdGet32 (PcdPL061GpioBase) + 0x404)
@@ -46,9 +47,5 @@
// All bits low except one bit high, native bit length
#define GPIO_PIN_MASK(Pin) (1UL << ((UINTN)(Pin)))
// All bits low except one bit high, restricted to 8 bits (i.e. ensures zeros above 8bits)
#define GPIO_PIN_MASK_HIGH_8BIT(Pin) (GPIO_PIN_MASK(Pin) && 0xFF)
// All bits high except one bit low, restricted to 8 bits (i.e. ensures zeros above 8bits)
#define GPIO_PIN_MASK_LOW_8BIT(Pin) ((~GPIO_PIN_MASK(Pin)) && 0xFF)
#endif // __PL061_GPIO_H__