aboutsummaryrefslogtreecommitdiff
path: root/02.5-collatz/src/clock.c
diff options
context:
space:
mode:
Diffstat (limited to '02.5-collatz/src/clock.c')
-rw-r--r--02.5-collatz/src/clock.c106
1 files changed, 0 insertions, 106 deletions
diff --git a/02.5-collatz/src/clock.c b/02.5-collatz/src/clock.c
deleted file mode 100644
index 75bac97..0000000
--- a/02.5-collatz/src/clock.c
+++ /dev/null
@@ -1,106 +0,0 @@
-/*
- * This file sets the system clock to its full glory of 80Mhz
- */
-
-#include "clock.h"
-#include <stdint.h>
-#include "flash.h"
-#include "gpio.h"
-#include "spin.h"
-
-#define TIMEOUT 10000
-
-int pll_off()
-{
- uint32_t c;
-
- RCC.c_r &= ~BIT(24); /* Turn off pll. */
- for (c = 0; c < TIMEOUT && RCC.c_r & BIT(25); ++c)
- ; /* Wait for OFF. */
-
- if (c == TIMEOUT) {
- return E_TIMEOUT;
- }
-
- return 0;
-}
-
-int pll_on()
-{
- uint32_t c;
-
- RCC.c_r |= BIT(24); /* Turn on PLL. */
- for (c = 0; c < TIMEOUT && !(RCC.c_r & BIT(25)); ++c)
- ; /* Wait for RDY. */
-
- if (c == TIMEOUT) {
- return E_TIMEOUT;
- }
-
- return 0;
-}
-
-int configure_pll(
- uint8_t pllp_div_factor, pll_divisor_t pllr, /* System clock divisor. */
- pll_divisor_t pllq, /* Divison factor for PLL48M1CLK. */
- pllp_divisor_t pllp, /* Divison factor for PLLSAI2CLK. */
- uint8_t plln, /* PLL numerator. */
- pllm_divisor_t pllm, /* PLL denominator. */
- pll_src_t pllsrc /* PLL source */)
-{
- if (RCC.c_r & BIT(25)) {
- /* PLL must be off to configure it. */
- return E_NOT_OFF;
- }
-
- /* Make sure inputs are valid. */
- if (pllp_div_factor == 1 || pllp_div_factor > 31) {
- return E_BADPLLP_DIV;
- }
- if (plln < 8 || plln > 86) {
- return E_BADPLLN;
- }
-
- RCC.pllcfg_r = (pllp_div_factor << 27) | (pllr << 24) | (pllq << 20) |
- (pllp << 16) | (plln << 8) | (pllm << 4) | (pllsrc << 0);
-
- return 0;
-}
-
-int set_system_clock_MHz(uint8_t mhz)
-{
- /* Set the source of the system colck to MSI temporarily. */
- set_system_clock_src(SYSTEM_CLOCK_SRC_MSI);
-
- if (mhz <= 8 || mhz > 80) {
- return E_BAD_ARG;
- }
-
- pll_off();
-
- configure_pll(
- 0 /* pllp_div_factor */, PLL_DIVISOR_4 /* pllr: VCO / 4 = mhz MHz. */,
- PLL_DIVISOR_4 /* pllq: VCO / 4 = mhz MHz */, PLLP_DIVISOR_7 /* pllp */,
-
- /* The following set the frequency of VCO to (mhz*4)MHz: mhz * 1 * 4MHz.
- */
- mhz /* plln | mhz */, PLLM_DIVISOR_1 /* pllm | 01 */,
- PLL_SRC_MSI /* pll src | 04 Mhz */);
-
- pll_on();
-
- /* Configure the flash to have 4 wait states. This is required at
- * 80 MHz. */
- FLASH.ac_r &= ~0x07;
- FLASH.ac_r |= 0x04;
-
- /* Set the source of the system colck to PLL. */
- set_system_clock_src(SYSTEM_CLOCK_SRC_PLL);
- return 0;
-}
-
-int set_system_clock_src(system_clock_src_t src)
-{
- uint8_t value = RCC.cfg_r & ~0x03;
- RCC.cfg_r = value | src;
-}