hw/misc/stm32l4x5_rcc: Add an internal clock multiplexer object

This object is used to represent every multiplexer in the clock tree as
well as every clock output, every presecaler, frequency multiplier, etc.
This allows to use a generic approach for every component of the clock tree
(except the PLLs).

The migration handling is based on hw/misc/zynq_sclr.c.
Three phase reset will be handled in a later commit.

Signed-off-by: Arnaud Minier <arnaud.minier@telecom-paris.fr>
Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20240303140643.81957-3-arnaud.minier@telecom-paris.fr
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 148 insertions, 0 deletions

diff --git a/include/hw/misc/stm32l4x5_rcc.h b/include/hw/misc/stm32l4x5_rcc.h
index 5157e96..6719be9 100644
--- a/include/hw/misc/stm32l4x5_rcc.h
+++ b/include/hw/misc/stm32l4x5_rcc.h
@@ -26,6 +26,122 @@ OBJECT_DECLARE_SIMPLE_TYPE(Stm32l4x5RccState, STM32L4X5_RCC)
 
 /* In the Stm32l4x5 clock tree, mux have at most 7 sources */
 #define RCC_NUM_CLOCK_MUX_SRC 7
+/* NB: Prescaler are assimilated to mux with one source and one output */
+typedef enum RccClockMux {
+    /* Internal muxes that arent't exposed publicly to other peripherals */
+    RCC_CLOCK_MUX_SYSCLK,
+    RCC_CLOCK_MUX_PLL_INPUT,
+    RCC_CLOCK_MUX_HCLK,
+    RCC_CLOCK_MUX_PCLK1,
+    RCC_CLOCK_MUX_PCLK2,
+    RCC_CLOCK_MUX_HSE_OVER_32,
+    RCC_CLOCK_MUX_LCD_AND_RTC_COMMON,
+
+    /* Muxes with a publicly available output */
+    RCC_CLOCK_MUX_CORTEX_REFCLK,
+    RCC_CLOCK_MUX_USART1,
+    RCC_CLOCK_MUX_USART2,
+    RCC_CLOCK_MUX_USART3,
+    RCC_CLOCK_MUX_UART4,
+    RCC_CLOCK_MUX_UART5,
+    RCC_CLOCK_MUX_LPUART1,
+    RCC_CLOCK_MUX_I2C1,
+    RCC_CLOCK_MUX_I2C2,
+    RCC_CLOCK_MUX_I2C3,
+    RCC_CLOCK_MUX_LPTIM1,
+    RCC_CLOCK_MUX_LPTIM2,
+    RCC_CLOCK_MUX_SWPMI1,
+    RCC_CLOCK_MUX_MCO,
+    RCC_CLOCK_MUX_LSCO,
+    RCC_CLOCK_MUX_DFSDM1,
+    RCC_CLOCK_MUX_ADC,
+    RCC_CLOCK_MUX_CLK48,
+    RCC_CLOCK_MUX_SAI1,
+    RCC_CLOCK_MUX_SAI2,
+
+    /*
+     * Mux that have only one input and one output assigned to as peripheral.
+     * They could be direct lines but it is simpler
+     * to use the same logic for all outputs.
+     */
+    /* - AHB1 */
+    RCC_CLOCK_MUX_TSC,
+    RCC_CLOCK_MUX_CRC,
+    RCC_CLOCK_MUX_FLASH,
+    RCC_CLOCK_MUX_DMA2,
+    RCC_CLOCK_MUX_DMA1,
+
+    /* - AHB2 */
+    RCC_CLOCK_MUX_RNG,
+    RCC_CLOCK_MUX_AES,
+    RCC_CLOCK_MUX_OTGFS,
+    RCC_CLOCK_MUX_GPIOA,
+    RCC_CLOCK_MUX_GPIOB,
+    RCC_CLOCK_MUX_GPIOC,
+    RCC_CLOCK_MUX_GPIOD,
+    RCC_CLOCK_MUX_GPIOE,
+    RCC_CLOCK_MUX_GPIOF,
+    RCC_CLOCK_MUX_GPIOG,
+    RCC_CLOCK_MUX_GPIOH,
+
+    /* - AHB3 */
+    RCC_CLOCK_MUX_QSPI,
+    RCC_CLOCK_MUX_FMC,
+
+    /* - APB1 */
+    RCC_CLOCK_MUX_OPAMP,
+    RCC_CLOCK_MUX_DAC1,
+    RCC_CLOCK_MUX_PWR,
+    RCC_CLOCK_MUX_CAN1,
+    RCC_CLOCK_MUX_SPI3,
+    RCC_CLOCK_MUX_SPI2,
+    RCC_CLOCK_MUX_WWDG,
+    RCC_CLOCK_MUX_LCD,
+    RCC_CLOCK_MUX_TIM7,
+    RCC_CLOCK_MUX_TIM6,
+    RCC_CLOCK_MUX_TIM5,
+    RCC_CLOCK_MUX_TIM4,
+    RCC_CLOCK_MUX_TIM3,
+    RCC_CLOCK_MUX_TIM2,
+
+    /* - APB2 */
+    RCC_CLOCK_MUX_TIM17,
+    RCC_CLOCK_MUX_TIM16,
+    RCC_CLOCK_MUX_TIM15,
+    RCC_CLOCK_MUX_TIM8,
+    RCC_CLOCK_MUX_SPI1,
+    RCC_CLOCK_MUX_TIM1,
+    RCC_CLOCK_MUX_SDMMC1,
+    RCC_CLOCK_MUX_FW,
+    RCC_CLOCK_MUX_SYSCFG,
+
+    /* - BDCR */
+    RCC_CLOCK_MUX_RTC,
+
+    /* - OTHER */
+    RCC_CLOCK_MUX_CORTEX_FCLK,
+
+    RCC_NUM_CLOCK_MUX
+} RccClockMux;
+
+typedef struct RccClockMuxState {
+    DeviceState parent_obj;
+
+    RccClockMux id;
+    Clock *srcs[RCC_NUM_CLOCK_MUX_SRC];
+    Clock *out;
+    bool enabled;
+    uint32_t src;
+    uint32_t multiplier;
+    uint32_t divider;
+
+    /*
+     * Used by clock srcs update callback to retrieve both the clock and the
+     * source number.
+     */
+    struct RccClockMuxState *backref[RCC_NUM_CLOCK_MUX_SRC];
+} RccClockMuxState;
+
 struct Stm32l4x5RccState {
     SysBusDevice parent_obj;
 
@@ -71,6 +187,9 @@ struct Stm32l4x5RccState {
     Clock *sai1_extclk;
     Clock *sai2_extclk;
 
+    /* Muxes ~= outputs */
+    RccClockMuxState clock_muxes[RCC_NUM_CLOCK_MUX];
+
     qemu_irq irq;
     uint64_t hse_frequency;
     uint64_t sai1_extclk_frequency;
diff --git a/include/hw/misc/stm32l4x5_rcc_internals.h b/include/hw/misc/stm32l4x5_rcc_internals.h
index 331ea30..4aa8368 100644
--- a/include/hw/misc/stm32l4x5_rcc_internals.h
+++ b/include/hw/misc/stm32l4x5_rcc_internals.h
@@ -21,6 +21,8 @@
 #include "hw/registerfields.h"
 #include "hw/misc/stm32l4x5_rcc.h"
 
+#define TYPE_RCC_CLOCK_MUX "stm32l4x5-rcc-clock-mux"
+OBJECT_DECLARE_SIMPLE_TYPE(RccClockMuxState, RCC_CLOCK_MUX)
 
 /* Register map */
 REG32(CR, 0x00)
@@ -283,4 +285,31 @@ REG32(CSR, 0x94)
                             R_CSR_FWRSTF_MASK   | \
                             R_CSR_LSIRDY_MASK)
 
+typedef enum RccClockMuxSource {
+    RCC_CLOCK_MUX_SRC_GND = 0,
+    RCC_CLOCK_MUX_SRC_HSI,
+    RCC_CLOCK_MUX_SRC_HSE,
+    RCC_CLOCK_MUX_SRC_MSI,
+    RCC_CLOCK_MUX_SRC_LSI,
+    RCC_CLOCK_MUX_SRC_LSE,
+    RCC_CLOCK_MUX_SRC_SAI1_EXTCLK,
+    RCC_CLOCK_MUX_SRC_SAI2_EXTCLK,
+    RCC_CLOCK_MUX_SRC_PLL,
+    RCC_CLOCK_MUX_SRC_PLLSAI1,
+    RCC_CLOCK_MUX_SRC_PLLSAI2,
+    RCC_CLOCK_MUX_SRC_PLLSAI3,
+    RCC_CLOCK_MUX_SRC_PLL48M1,
+    RCC_CLOCK_MUX_SRC_PLL48M2,
+    RCC_CLOCK_MUX_SRC_PLLADC1,
+    RCC_CLOCK_MUX_SRC_PLLADC2,
+    RCC_CLOCK_MUX_SRC_SYSCLK,
+    RCC_CLOCK_MUX_SRC_HCLK,
+    RCC_CLOCK_MUX_SRC_PCLK1,
+    RCC_CLOCK_MUX_SRC_PCLK2,
+    RCC_CLOCK_MUX_SRC_HSE_OVER_32,
+    RCC_CLOCK_MUX_SRC_LCD_AND_RTC_COMMON,
+
+    RCC_CLOCK_MUX_SRC_NUMBER,
+} RccClockMuxSource;
+
 #endif /* HW_STM32L4X5_RCC_INTERNALS_H */