LM
/
u-boot
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
u-boot/drivers/mtd/spi/sunxi_spi_spl.c

287 lines
8.6 KiB
C
Raw Blame History

/*
* 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;
}
}
/*****************************************************************************/
static int spl_spi_load_image(struct spl_image_info *spl_image,
struct spl_boot_device *bootdev)
{
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(spl_image, 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;
}
/* Use priorty 0 to override the default if it happens to be linked in */
SPL_LOAD_IMAGE_METHOD(0, BOOT_DEVICE_SPI, spl_spi_load_image);
Reference in New Issue View Git Blame Copy Permalink