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author | Vikas Manocha <vikas.manocha@st.com> | 2017-04-11 01:02:51 +0300 |
---|---|---|
committer | Tom Rini <trini@konsulko.com> | 2017-05-08 18:39:02 +0300 |
commit | bf1ae4426b89bd8b3e036e012acc4bc88fec4c6e (patch) | |
tree | 6346f4d7e51595d399785308c75575530169a0b8 /drivers/ram | |
parent | 890bafd752460b79c607e829f58bf88f0f8484b7 (diff) | |
download | u-boot-bf1ae4426b89bd8b3e036e012acc4bc88fec4c6e.tar.xz |
stm32f7: sdram: move sdram driver code to ram drivers area
Signed-off-by: Vikas Manocha <vikas.manocha@st.com>
cc: Christophe KERELLO <christophe.kerello@st.com>
Diffstat (limited to 'drivers/ram')
-rw-r--r-- | drivers/ram/Kconfig | 8 | ||||
-rw-r--r-- | drivers/ram/Makefile | 1 | ||||
-rw-r--r-- | drivers/ram/stm32_sdram.c | 119 |
3 files changed, 128 insertions, 0 deletions
diff --git a/drivers/ram/Kconfig b/drivers/ram/Kconfig index ff09f226df..61afd7a92a 100644 --- a/drivers/ram/Kconfig +++ b/drivers/ram/Kconfig @@ -16,3 +16,11 @@ config SPL_RAM If this is acceptable and you have a need to use RAM drivers in SPL, enable this option. It might provide a cleaner interface to setting up RAM (e.g. SDRAM / DDR) within SPL. + +config STM32_SDRAM + bool "Enable STM32 SDRAM support" + depends on RAM + help + STM32F7 family devices support flexible memory controller(FMC) to + support external memories like sdram, psram & nand. + This driver is for the sdram memory interface with the FMC. diff --git a/drivers/ram/Makefile b/drivers/ram/Makefile index 0e102491a4..ecb036dfba 100644 --- a/drivers/ram/Makefile +++ b/drivers/ram/Makefile @@ -6,3 +6,4 @@ # obj-$(CONFIG_RAM) += ram-uclass.o obj-$(CONFIG_SANDBOX) += sandbox_ram.o +obj-$(CONFIG_STM32_SDRAM) += stm32_sdram.o diff --git a/drivers/ram/stm32_sdram.c b/drivers/ram/stm32_sdram.c new file mode 100644 index 0000000000..13f896484e --- /dev/null +++ b/drivers/ram/stm32_sdram.c @@ -0,0 +1,119 @@ +/* + * (C) Copyright 2017 + * Vikas Manocha, <vikas.manocha@st.com> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <asm/io.h> +#include <asm/arch/fmc.h> +#include <asm/arch/stm32.h> + +static inline u32 _ns2clk(u32 ns, u32 freq) +{ + u32 tmp = freq/1000000; + return (tmp * ns) / 1000; +} + +#define NS2CLK(ns) (_ns2clk(ns, freq)) + +/* + * Following are timings for IS42S16400J, from corresponding datasheet + */ +#define SDRAM_CAS 3 /* 3 cycles */ +#define SDRAM_NB 1 /* Number of banks */ +#define SDRAM_MWID 1 /* 16 bit memory */ + +#define SDRAM_NR 0x1 /* 12-bit row */ +#define SDRAM_NC 0x0 /* 8-bit col */ +#define SDRAM_RBURST 0x1 /* Single read requests always as bursts */ +#define SDRAM_RPIPE 0x0 /* No HCLK clock cycle delay */ + +#define SDRAM_TRRD NS2CLK(12) +#define SDRAM_TRCD NS2CLK(18) +#define SDRAM_TRP NS2CLK(18) +#define SDRAM_TRAS NS2CLK(42) +#define SDRAM_TRC NS2CLK(60) +#define SDRAM_TRFC NS2CLK(60) +#define SDRAM_TCDL (1 - 1) +#define SDRAM_TRDL NS2CLK(12) +#define SDRAM_TBDL (1 - 1) +#define SDRAM_TREF (NS2CLK(64000000 / 8192) - 20) +#define SDRAM_TCCD (1 - 1) + +#define SDRAM_TXSR SDRAM_TRFC /* Row cycle time after precharge */ +#define SDRAM_TMRD 1 /* Page 10, Mode Register Set */ + + +/* Last data in to row precharge, need also comply ineq on page 1648 */ +#define SDRAM_TWR max(\ + (int)max((int)SDRAM_TRDL, (int)(SDRAM_TRAS - SDRAM_TRCD)), \ + (int)(SDRAM_TRC - SDRAM_TRCD - SDRAM_TRP)\ + ) + + +#define SDRAM_MODE_BL_SHIFT 0 +#define SDRAM_MODE_CAS_SHIFT 4 +#define SDRAM_MODE_BL 0 +#define SDRAM_MODE_CAS SDRAM_CAS + +int stm32_sdram_init(void) +{ + u32 freq; + + /* + * Get frequency for NS2CLK calculation. + */ + freq = clock_get(CLOCK_AHB) / CONFIG_SYS_RAM_FREQ_DIV; + + writel(CONFIG_SYS_RAM_FREQ_DIV << FMC_SDCR_SDCLK_SHIFT + | SDRAM_CAS << FMC_SDCR_CAS_SHIFT + | SDRAM_NB << FMC_SDCR_NB_SHIFT + | SDRAM_MWID << FMC_SDCR_MWID_SHIFT + | SDRAM_NR << FMC_SDCR_NR_SHIFT + | SDRAM_NC << FMC_SDCR_NC_SHIFT + | SDRAM_RPIPE << FMC_SDCR_RPIPE_SHIFT + | SDRAM_RBURST << FMC_SDCR_RBURST_SHIFT, + &STM32_SDRAM_FMC->sdcr1); + + writel(SDRAM_TRCD << FMC_SDTR_TRCD_SHIFT + | SDRAM_TRP << FMC_SDTR_TRP_SHIFT + | SDRAM_TWR << FMC_SDTR_TWR_SHIFT + | SDRAM_TRC << FMC_SDTR_TRC_SHIFT + | SDRAM_TRAS << FMC_SDTR_TRAS_SHIFT + | SDRAM_TXSR << FMC_SDTR_TXSR_SHIFT + | SDRAM_TMRD << FMC_SDTR_TMRD_SHIFT, + &STM32_SDRAM_FMC->sdtr1); + + writel(FMC_SDCMR_BANK_1 | FMC_SDCMR_MODE_START_CLOCK, + &STM32_SDRAM_FMC->sdcmr); + udelay(200); /* 200 us delay, page 10, "Power-Up" */ + FMC_BUSY_WAIT(); + + writel(FMC_SDCMR_BANK_1 | FMC_SDCMR_MODE_PRECHARGE, + &STM32_SDRAM_FMC->sdcmr); + udelay(100); + FMC_BUSY_WAIT(); + + writel((FMC_SDCMR_BANK_1 | FMC_SDCMR_MODE_AUTOREFRESH + | 7 << FMC_SDCMR_NRFS_SHIFT), &STM32_SDRAM_FMC->sdcmr); + udelay(100); + FMC_BUSY_WAIT(); + + writel(FMC_SDCMR_BANK_1 | (SDRAM_MODE_BL << SDRAM_MODE_BL_SHIFT + | SDRAM_MODE_CAS << SDRAM_MODE_CAS_SHIFT) + << FMC_SDCMR_MODE_REGISTER_SHIFT | FMC_SDCMR_MODE_WRITE_MODE, + &STM32_SDRAM_FMC->sdcmr); + udelay(100); + FMC_BUSY_WAIT(); + + writel(FMC_SDCMR_BANK_1 | FMC_SDCMR_MODE_NORMAL, + &STM32_SDRAM_FMC->sdcmr); + FMC_BUSY_WAIT(); + + /* Refresh timer */ + writel(SDRAM_TREF, &STM32_SDRAM_FMC->sdrtr); + + return 0; +} |