aboutsummaryrefslogtreecommitdiff
path: root/stm-fmc.h
diff options
context:
space:
mode:
authorPaul Selkirk <paul@psgd.org>2019-04-03 17:41:10 -0400
committerPaul Selkirk <paul@psgd.org>2019-04-03 17:41:10 -0400
commita590fe12485603003101b5a4ba2f616083d040f4 (patch)
tree36819a49c479e2d4d37005902ab2f87a2015839a /stm-fmc.h
parent9006c25bd73c00ff861cccbce4595e6c932f4ace (diff)
parent624527539a83dbfd0dc2f03fda1cff14a1669811 (diff)
Merge branch 'fmc_clk_60mhz' to 'master'
Diffstat (limited to 'stm-fmc.h')
-rw-r--r--stm-fmc.h52
1 files changed, 4 insertions, 48 deletions
diff --git a/stm-fmc.h b/stm-fmc.h
index eab053d..92b261b 100644
--- a/stm-fmc.h
+++ b/stm-fmc.h
@@ -39,12 +39,6 @@
#define FMC_FPGA_BASE_ADDR 0x60000000
#define FMC_FPGA_ADDR_MASK 0x03FFFFFC // there are 26 physical lines, but "only" 24 usable for now
-#define FMC_FPGA_NWAIT_MAX_POLL_TICKS 10
-
-#define FMC_GPIO_PORT_NWAIT GPIOD
-#define FMC_GPIO_PIN_NWAIT GPIO_PIN_6
-
-#define FMC_NWAIT_IDLE GPIO_PIN_SET
#define fmc_af_gpio(port, pins) \
GPIO_InitStruct.Pin = pins; \
@@ -58,60 +52,22 @@
extern void fmc_init(void);
-static inline HAL_StatusTypeDef _fmc_nwait_idle(void)
-{
- int cnt;
-
- // poll NWAIT (number of iterations is limited)
- for (cnt=0; cnt<FMC_FPGA_NWAIT_MAX_POLL_TICKS; cnt++)
- {
- // read pin state
- if (HAL_GPIO_ReadPin(FMC_GPIO_PORT_NWAIT, FMC_GPIO_PIN_NWAIT) == FMC_NWAIT_IDLE)
- return HAL_OK;
- }
-
- return HAL_ERROR;
-}
-
-static inline HAL_StatusTypeDef fmc_write_32(const uint32_t addr, const uint32_t data)
+static inline void fmc_write_32(const uint32_t addr, const uint32_t data)
{
// calculate target fpga address
uint32_t *ptr = (uint32_t *) (FMC_FPGA_BASE_ADDR + (addr & FMC_FPGA_ADDR_MASK));
// write data to fpga
*ptr = data;
-
- // wait for transaction to complete
- return _fmc_nwait_idle();
}
-static inline HAL_StatusTypeDef fmc_read_32(const uint32_t addr, uint32_t * const data)
+static inline void fmc_read_32(const uint32_t addr, uint32_t * const data)
{
// calculate target fpga address
uint32_t *ptr = (uint32_t *) (FMC_FPGA_BASE_ADDR + (addr & FMC_FPGA_ADDR_MASK));
- /* Pavel says:
- * The short story is like, on one hand STM32 has a dedicated FMC_NWAIT
- * pin, that can be used in variable-latency data transfer mode. On the
- * other hand STM32 also has a very nasty hardware bug associated with
- * FMC_WAIT, that causes processor to freeze under certain conditions.
- * Because of this FMC_NWAIT cannot be used and FPGA can't properly signal
- * to STM32, when data transfer is done. Because of that we have to read
- * two times.
- */
-
- HAL_StatusTypeDef status;
-
- *data = *ptr;
- status = _fmc_nwait_idle();
-
- if (status != HAL_OK)
- return status;
-
- *data = *ptr;
- status = _fmc_nwait_idle();
-
- return status;
+ // read data from fpga
+ *data = *ptr;
}
#endif /* __STM_FMC_H */