src/soc/amd/common/block/spi/fch_spi.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <amdblocks/chip.h>
   4 #include <amdblocks/lpc.h>
   5 #include <amdblocks/psp_efs.h>
   6 #include <amdblocks/spi.h>
   7 #include <console/console.h>
   8 #include <device/mmio.h>
   9 #include <soc/iomap.h>
  10 #include <soc/lpc.h>
  11 #include <stdint.h>
  12
  13 static const char *spi_speed_str[8] = {
  14         "66.66 Mhz",
  15         "33.33 MHz",
  16         "22.22 MHz",
  17         "16.66 MHz",
  18         "100 MHz",
  19         "800 KHz",
  20         "Invalid",
  21         "Invalid"
  22 };
  23
  24 static const char *read_mode_str[8] = {
  25         "Normal Read (up to 33M)",
  26         "Reserved",
  27         "Dual IO (1-1-2)",
  28         "Quad IO (1-1-4)",
  29         "Dual IO (1-2-2)",
  30         "Quad IO (1-4-4)",
  31         "Normal Read (up to 66M)",
  32         "Fast Read"
  33 };
  34
  35 void show_spi_speeds_and_modes(void)
  36 {
  37         uint16_t val16 = spi_read16(SPI100_SPEED_CONFIG);
  38         uint32_t val32 = spi_read32(SPI_CNTRL0);
  39
  40         printk(BIOS_DEBUG, "SPI normal read speed: %s\n",
  41                spi_speed_str[DECODE_SPI_NORMAL_SPEED(val16)]);
  42         printk(BIOS_DEBUG, "SPI fast read speed: %s\n",
  43                spi_speed_str[DECODE_SPI_FAST_SPEED(val16)]);
  44         printk(BIOS_DEBUG, "SPI alt read speed: %s\n",
  45                spi_speed_str[DECODE_SPI_ALT_SPEED(val16)]);
  46         printk(BIOS_DEBUG, "SPI TPM read speed: %s\n",
  47                spi_speed_str[DECODE_SPI_TPM_SPEED(val16)]);
  48         printk(BIOS_DEBUG, "SPI100: %s\n",
  49                spi_read16(SPI100_ENABLE) & SPI_USE_SPI100 ? "Enabled" : "Disabled");
  50         printk(BIOS_DEBUG, "SPI Read Mode: %s\n", read_mode_str[DECODE_SPI_READ_MODE(val32)]);
  51 }
  52
  53 void __weak mainboard_spi_cfg_override(uint8_t *fast_speed, uint8_t *read_mode)
  54 {
  55         /* No overriding SPI speeds. */
  56 }
  57
  58 static uint8_t lower_speed(uint8_t speed1, uint8_t speed2)
  59 {
  60         uint8_t speeds[] = {SPI_SPEED_800K, SPI_SPEED_16M, SPI_SPEED_22M,
  61                             SPI_SPEED_33M,  SPI_SPEED_66M, SPI_SPEED_100M};
  62
  63         for (int i = 0; i < ARRAY_SIZE(speeds); i++) {
  64                 if (speed1 == speeds[i])
  65                         return speed1;
  66                 if (speed2 == speeds[i])
  67                         return speed2;
  68         }
  69
  70         /* Fall back to 16MHz if we got invalid speed values */
  71         return SPI_SPEED_16M;
  72 }
  73
  74 static void fch_spi_set_spi100(uint8_t norm, uint8_t fast, uint8_t alt, uint8_t tpm)
  75 {
  76         spi_write16(SPI100_SPEED_CONFIG, SPI_SPEED_CFG(norm, fast, alt, tpm));
  77         spi_write16(SPI100_ENABLE, SPI_USE_SPI100 | spi_read16(SPI100_ENABLE));
  78 }
  79
  80 static void fch_spi_configure_4dw_burst(void)
  81 {
  82         uint16_t val = spi_read16(SPI100_HOST_PREF_CONFIG);
  83
  84         if (CONFIG(SOC_AMD_COMMON_BLOCK_SPI_4DW_BURST))
  85                 val |= SPI_RD4DW_EN_HOST;
  86         else
  87                 val &= ~SPI_RD4DW_EN_HOST;
  88
  89         spi_write16(SPI100_HOST_PREF_CONFIG, val);
  90 }
  91
  92 static void fch_spi_set_read_mode(u32 mode)
  93 {
  94         uint32_t val = spi_read32(SPI_CNTRL0) & ~SPI_READ_MODE_MASK;
  95
  96         spi_write32(SPI_CNTRL0, val | SPI_READ_MODE(mode));
  97 }
  98
  99 void fch_spi_config_modes(void)
 100 {
 101         uint8_t read_mode, fast_speed;
 102         uint8_t normal_speed = CONFIG_NORMAL_READ_SPI_SPEED;
 103         uint8_t alt_speed = CONFIG_ALT_SPI_SPEED;
 104         uint8_t tpm_speed = CONFIG_TPM_SPI_SPEED;
 105
 106         if (!read_efs_spi_settings(&read_mode, &fast_speed)) {
 107                 read_mode = CONFIG_EFS_SPI_READ_MODE;
 108                 fast_speed = CONFIG_EFS_SPI_SPEED;
 109         }
 110         mainboard_spi_cfg_override(&fast_speed, &read_mode);
 111
 112         if (fast_speed != CONFIG_EFS_SPI_SPEED) {
 113                 normal_speed = lower_speed(normal_speed, fast_speed);
 114                 tpm_speed = lower_speed(tpm_speed, fast_speed);
 115                 alt_speed = lower_speed(alt_speed, fast_speed);
 116         }
 117
 118         fch_spi_set_read_mode((u32)read_mode);
 119         fch_spi_set_spi100(normal_speed, fast_speed, alt_speed, tpm_speed);
 120 }
 121
 122 void fch_spi_early_init(void)
 123 {
 124         lpc_enable_spi_rom(SPI_ROM_ENABLE);
 125         lpc_enable_spi_prefetch();
 126         fch_spi_configure_4dw_burst();
 127         fch_spi_config_modes();
 128 }