The older i.MX8M Mini Verdin SoMs may came with 20 MHz SPI CAN controller oscillator, the newer SoMs always use 40 MHz oscillator. Handle both by overriding the oscillator frequency just before booting the kernel.
These are the known variants with 20 MHz oscillator: - 0055, V1.1A, V1.1B, V1.1C and V1.1D, use a 20MHz oscillator - 0059, V1.1A and V1.1B, use a 20MHz oscillator
Signed-off-by: Marek Vasut marex@denx.de --- Cc: "NXP i.MX U-Boot Team" uboot-imx@nxp.com Cc: Fabio Estevam festevam@gmail.com Cc: Francesco Dolcini francesco.dolcini@toradex.com Cc: Marcel Ziswiler marcel.ziswiler@toradex.com Cc: Philippe Schenker philippe.schenker@toradex.com Cc: Martyn Welch martyn.welch@collabora.com Cc: Stefano Babic sbabic@denx.de Cc: u-boot@lists.denx.de --- board/toradex/verdin-imx8mm/verdin-imx8mm.c | 30 +++++++++++++++++++++ 1 file changed, 30 insertions(+)
diff --git a/board/toradex/verdin-imx8mm/verdin-imx8mm.c b/board/toradex/verdin-imx8mm/verdin-imx8mm.c index 55c02653da6..b4a443ebfb0 100644 --- a/board/toradex/verdin-imx8mm/verdin-imx8mm.c +++ b/board/toradex/verdin-imx8mm/verdin-imx8mm.c @@ -125,6 +125,36 @@ int board_phys_sdram_size(phys_size_t *size) #if defined(CONFIG_OF_LIBFDT) && defined(CONFIG_OF_BOARD_SETUP) int ft_board_setup(void *blob, struct bd_info *bd) { + const char *canoscpath = "/oscillator"; + int freq = 40000000; /* 40 MHz is used on most variants */ + int canoscoff, ret; + + canoscoff = fdt_path_offset(blob, canoscpath); + if (canoscoff < 0) /* No CAN oscillator found. */ + goto exit; + + /* + * The actual "prodid" (PID4 in Toradex naming) that have the CAN + * functionality are 0055 and 0059. Special case 20 MHz variant + * here: + * - 0055, V1.1A, V1.1B, V1.1C and V1.1D, use a 20MHz oscillator + * - 0059, V1.1A and V1.1B, use a 20MHz oscillator + */ + if ((tdx_hw_tag.ver_major == 1 && tdx_hw_tag.ver_minor == 1) && + ((tdx_hw_tag.prodid == VERDIN_IMX8MMQ_IT && + tdx_hw_tag.ver_assembly <= 1) || /* 0055 rev. A or B */ + (tdx_hw_tag.prodid == VERDIN_IMX8MMQ_WIFI_BT_IT && + tdx_hw_tag.ver_assembly <= 4))) { /* 0059 rev. A/B/C/D */ + freq = 20000000; + } + + ret = fdt_setprop_u32(blob, canoscoff, "clock-frequency", freq); + if (ret < 0) { + printf("Failed to set CAN oscillator clock-frequency, ret=%d\n", + ret); + } + +exit: return ft_common_board_setup(blob, bd); } #endif