--- /dev/null
+/*
+ * Copyright (C) 2016 Siarhei Siamashka <siarhei.siamashka@gmail.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <spl.h>
+#include <asm/gpio.h>
+#include <asm/io.h>
+
+#ifdef CONFIG_SPL_OS_BOOT
+#error CONFIG_SPL_OS_BOOT is not supported yet
+#endif
+
+/*
+ * This is a very simple U-Boot image loading implementation, trying to
+ * replicate what the boot ROM is doing when loading the SPL. Because we
+ * know the exact pins where the SPI Flash is connected and also know
+ * that the Read Data Bytes (03h) command is supported, the hardware
+ * configuration is very simple and we don't need the extra flexibility
+ * of the SPI framework. Moreover, we rely on the default settings of
+ * the SPI controler hardware registers and only adjust what needs to
+ * be changed. This is good for the code size and this implementation
+ * adds less than 400 bytes to the SPL.
+ *
+ * There are two variants of the SPI controller in Allwinner SoCs:
+ * A10/A13/A20 (sun4i variant) and everything else (sun6i variant).
+ * Both of them are supported.
+ *
+ * The pin mixing part is SoC specific and only A10/A13/A20/H3/A64 are
+ * supported at the moment.
+ */
+
+/*****************************************************************************/
+/* SUN4I variant of the SPI controller */
+/*****************************************************************************/
+
+#define SUN4I_SPI0_CCTL (0x01C05000 + 0x1C)
+#define SUN4I_SPI0_CTL (0x01C05000 + 0x08)
+#define SUN4I_SPI0_RX (0x01C05000 + 0x00)
+#define SUN4I_SPI0_TX (0x01C05000 + 0x04)
+#define SUN4I_SPI0_FIFO_STA (0x01C05000 + 0x28)
+#define SUN4I_SPI0_BC (0x01C05000 + 0x20)
+#define SUN4I_SPI0_TC (0x01C05000 + 0x24)
+
+#define SUN4I_CTL_ENABLE BIT(0)
+#define SUN4I_CTL_MASTER BIT(1)
+#define SUN4I_CTL_TF_RST BIT(8)
+#define SUN4I_CTL_RF_RST BIT(9)
+#define SUN4I_CTL_XCH BIT(10)
+
+/*****************************************************************************/
+/* SUN6I variant of the SPI controller */
+/*****************************************************************************/
+
+#define SUN6I_SPI0_CCTL (0x01C68000 + 0x24)
+#define SUN6I_SPI0_GCR (0x01C68000 + 0x04)
+#define SUN6I_SPI0_TCR (0x01C68000 + 0x08)
+#define SUN6I_SPI0_FIFO_STA (0x01C68000 + 0x1C)
+#define SUN6I_SPI0_MBC (0x01C68000 + 0x30)
+#define SUN6I_SPI0_MTC (0x01C68000 + 0x34)
+#define SUN6I_SPI0_BCC (0x01C68000 + 0x38)
+#define SUN6I_SPI0_TXD (0x01C68000 + 0x200)
+#define SUN6I_SPI0_RXD (0x01C68000 + 0x300)
+
+#define SUN6I_CTL_ENABLE BIT(0)
+#define SUN6I_CTL_MASTER BIT(1)
+#define SUN6I_CTL_SRST BIT(31)
+#define SUN6I_TCR_XCH BIT(31)
+
+/*****************************************************************************/
+
+#define CCM_AHB_GATING0 (0x01C20000 + 0x60)
+#define CCM_SPI0_CLK (0x01C20000 + 0xA0)
+#define SUN6I_BUS_SOFT_RST_REG0 (0x01C20000 + 0x2C0)
+
+#define AHB_RESET_SPI0_SHIFT 20
+#define AHB_GATE_OFFSET_SPI0 20
+
+#define SPI0_CLK_DIV_BY_2 0x1000
+#define SPI0_CLK_DIV_BY_4 0x1001
+
+/*****************************************************************************/
+
+/*
+ * Allwinner A10/A20 SoCs were using pins PC0,PC1,PC2,PC23 for booting
+ * from SPI Flash, everything else is using pins PC0,PC1,PC2,PC3.
+ */
+static void spi0_pinmux_setup(unsigned int pin_function)
+{
+ unsigned int pin;
+
+ for (pin = SUNXI_GPC(0); pin <= SUNXI_GPC(2); pin++)
+ sunxi_gpio_set_cfgpin(pin, pin_function);
+
+ if (IS_ENABLED(CONFIG_MACH_SUN4I) || IS_ENABLED(CONFIG_MACH_SUN7I))
+ sunxi_gpio_set_cfgpin(SUNXI_GPC(23), pin_function);
+ else
+ sunxi_gpio_set_cfgpin(SUNXI_GPC(3), pin_function);
+}
+
+/*
+ * Setup 6 MHz from OSC24M (because the BROM is doing the same).
+ */
+static void spi0_enable_clock(void)
+{
+ /* Deassert SPI0 reset on SUN6I */
+ if (IS_ENABLED(CONFIG_SUNXI_GEN_SUN6I))
+ setbits_le32(SUN6I_BUS_SOFT_RST_REG0,
+ (1 << AHB_RESET_SPI0_SHIFT));
+
+ /* Open the SPI0 gate */
+ setbits_le32(CCM_AHB_GATING0, (1 << AHB_GATE_OFFSET_SPI0));
+
+ /* Divide by 4 */
+ writel(SPI0_CLK_DIV_BY_4, IS_ENABLED(CONFIG_SUNXI_GEN_SUN6I) ?
+ SUN6I_SPI0_CCTL : SUN4I_SPI0_CCTL);
+ /* 24MHz from OSC24M */
+ writel((1 << 31), CCM_SPI0_CLK);
+
+ if (IS_ENABLED(CONFIG_SUNXI_GEN_SUN6I)) {
+ /* Enable SPI in the master mode and do a soft reset */
+ setbits_le32(SUN6I_SPI0_GCR, SUN6I_CTL_MASTER |
+ SUN6I_CTL_ENABLE |
+ SUN6I_CTL_SRST);
+ /* Wait for completion */
+ while (readl(SUN6I_SPI0_GCR) & SUN6I_CTL_SRST)
+ ;
+ } else {
+ /* Enable SPI in the master mode and reset FIFO */
+ setbits_le32(SUN4I_SPI0_CTL, SUN4I_CTL_MASTER |
+ SUN4I_CTL_ENABLE |
+ SUN4I_CTL_TF_RST |
+ SUN4I_CTL_RF_RST);
+ }
+}
+
+static void spi0_disable_clock(void)
+{
+ /* Disable the SPI0 controller */
+ if (IS_ENABLED(CONFIG_SUNXI_GEN_SUN6I))
+ clrbits_le32(SUN6I_SPI0_GCR, SUN6I_CTL_MASTER |
+ SUN6I_CTL_ENABLE);
+ else
+ clrbits_le32(SUN4I_SPI0_CTL, SUN4I_CTL_MASTER |
+ SUN4I_CTL_ENABLE);
+
+ /* Disable the SPI0 clock */
+ writel(0, CCM_SPI0_CLK);
+
+ /* Close the SPI0 gate */
+ clrbits_le32(CCM_AHB_GATING0, (1 << AHB_GATE_OFFSET_SPI0));
+
+ /* Assert SPI0 reset on SUN6I */
+ if (IS_ENABLED(CONFIG_SUNXI_GEN_SUN6I))
+ clrbits_le32(SUN6I_BUS_SOFT_RST_REG0,
+ (1 << AHB_RESET_SPI0_SHIFT));
+}
+
+static int spi0_init(void)
+{
+ unsigned int pin_function = SUNXI_GPC_SPI0;
+ if (IS_ENABLED(CONFIG_MACH_SUN50I))
+ pin_function = SUN50I_GPC_SPI0;
+
+ spi0_pinmux_setup(pin_function);
+ spi0_enable_clock();
+}
+
+static void spi0_deinit(void)
+{
+ /* New SoCs can disable pins, older could only set them as input */
+ unsigned int pin_function = SUNXI_GPIO_INPUT;
+ if (IS_ENABLED(CONFIG_SUNXI_GEN_SUN6I))
+ pin_function = SUNXI_GPIO_DISABLE;
+
+ spi0_disable_clock();
+ spi0_pinmux_setup(pin_function);
+}
+
+/*****************************************************************************/
+
+#define SPI_READ_MAX_SIZE 60 /* FIFO size, minus 4 bytes of the header */
+
+static void sunxi_spi0_read_data(u8 *buf, u32 addr, u32 bufsize,
+ u32 spi_ctl_reg,
+ u32 spi_ctl_xch_bitmask,
+ u32 spi_fifo_reg,
+ u32 spi_tx_reg,
+ u32 spi_rx_reg,
+ u32 spi_bc_reg,
+ u32 spi_tc_reg,
+ u32 spi_bcc_reg)
+{
+ writel(4 + bufsize, spi_bc_reg); /* Burst counter (total bytes) */
+ writel(4, spi_tc_reg); /* Transfer counter (bytes to send) */
+ if (spi_bcc_reg)
+ writel(4, spi_bcc_reg); /* SUN6I also needs this */
+
+ /* Send the Read Data Bytes (03h) command header */
+ writeb(0x03, spi_tx_reg);
+ writeb((u8)(addr >> 16), spi_tx_reg);
+ writeb((u8)(addr >> 8), spi_tx_reg);
+ writeb((u8)(addr), spi_tx_reg);
+
+ /* Start the data transfer */
+ setbits_le32(spi_ctl_reg, spi_ctl_xch_bitmask);
+
+ /* Wait until everything is received in the RX FIFO */
+ while ((readl(spi_fifo_reg) & 0x7F) < 4 + bufsize)
+ ;
+
+ /* Skip 4 bytes */
+ readl(spi_rx_reg);
+
+ /* Read the data */
+ while (bufsize-- > 0)
+ *buf++ = readb(spi_rx_reg);
+
+ /* tSHSL time is up to 100 ns in various SPI flash datasheets */
+ udelay(1);
+}
+
+static void spi0_read_data(void *buf, u32 addr, u32 len)
+{
+ u8 *buf8 = buf;
+ u32 chunk_len;
+
+ while (len > 0) {
+ chunk_len = len;
+ if (chunk_len > SPI_READ_MAX_SIZE)
+ chunk_len = SPI_READ_MAX_SIZE;
+
+ if (IS_ENABLED(CONFIG_SUNXI_GEN_SUN6I)) {
+ sunxi_spi0_read_data(buf8, addr, chunk_len,
+ SUN6I_SPI0_TCR,
+ SUN6I_TCR_XCH,
+ SUN6I_SPI0_FIFO_STA,
+ SUN6I_SPI0_TXD,
+ SUN6I_SPI0_RXD,
+ SUN6I_SPI0_MBC,
+ SUN6I_SPI0_MTC,
+ SUN6I_SPI0_BCC);
+ } else {
+ sunxi_spi0_read_data(buf8, addr, chunk_len,
+ SUN4I_SPI0_CTL,
+ SUN4I_CTL_XCH,
+ SUN4I_SPI0_FIFO_STA,
+ SUN4I_SPI0_TX,
+ SUN4I_SPI0_RX,
+ SUN4I_SPI0_BC,
+ SUN4I_SPI0_TC,
+ 0);
+ }
+
+ len -= chunk_len;
+ buf8 += chunk_len;
+ addr += chunk_len;
+ }
+}
+
+/*****************************************************************************/
+
+int spl_spi_load_image(void)
+{
+ int err;
+ struct image_header *header;
+ header = (struct image_header *)(CONFIG_SYS_TEXT_BASE);
+
+ spi0_init();
+
+ spi0_read_data((void *)header, CONFIG_SYS_SPI_U_BOOT_OFFS, 0x40);
+ err = spl_parse_image_header(header);
+ if (err)
+ return err;
+
+ spi0_read_data((void *)spl_image.load_addr, CONFIG_SYS_SPI_U_BOOT_OFFS,
+ spl_image.size);
+
+ spi0_deinit();
+ return 0;
+}
projects / u-boot.git / commitdiff
