1*df730d94SMarco Felsch /* 2*df730d94SMarco Felsch * Copyright (c) 2023, Pengutronix. All rights reserved. 3*df730d94SMarco Felsch * 4*df730d94SMarco Felsch * SPDX-License-Identifier: BSD-3-Clause 5*df730d94SMarco Felsch */ 6*df730d94SMarco Felsch 7*df730d94SMarco Felsch #include <lib/mmio.h> 8*df730d94SMarco Felsch #include <platform_def.h> 9*df730d94SMarco Felsch 10*df730d94SMarco Felsch #define UCR1 0x80 11*df730d94SMarco Felsch #define UCR1_UARTEN BIT(0) 12*df730d94SMarco Felsch #define DOMAIN0_RUNNING(d) (((d) & 0x3) != 0) 13*df730d94SMarco Felsch 14*df730d94SMarco Felsch static struct imx_uart { 15*df730d94SMarco Felsch unsigned int ccm_reg; 16*df730d94SMarco Felsch unsigned int uart_base; 17*df730d94SMarco Felsch } imx8m_uart_info[] = { 18*df730d94SMarco Felsch { /* UART 1 */ 19*df730d94SMarco Felsch .ccm_reg = 0x4490, 20*df730d94SMarco Felsch .uart_base = 0x30860000, 21*df730d94SMarco Felsch }, { /* UART 2 */ 22*df730d94SMarco Felsch .ccm_reg = 0x44a0, 23*df730d94SMarco Felsch .uart_base = 0x30890000, 24*df730d94SMarco Felsch }, { /* UART 3 */ 25*df730d94SMarco Felsch .ccm_reg = 0x44b0, 26*df730d94SMarco Felsch .uart_base = 0x30880000, 27*df730d94SMarco Felsch }, { /* UART 4 */ 28*df730d94SMarco Felsch .ccm_reg = 0x44c0, 29*df730d94SMarco Felsch .uart_base = 0x30a60000, 30*df730d94SMarco Felsch } 31*df730d94SMarco Felsch }; 32*df730d94SMarco Felsch 33*df730d94SMarco Felsch unsigned int imx8m_uart_get_base(void) 34*df730d94SMarco Felsch { 35*df730d94SMarco Felsch unsigned int i; 36*df730d94SMarco Felsch 37*df730d94SMarco Felsch for (i = 0; i < ARRAY_SIZE(imx8m_uart_info); i++) { 38*df730d94SMarco Felsch uint32_t val; 39*df730d94SMarco Felsch 40*df730d94SMarco Felsch /* 41*df730d94SMarco Felsch * At least check that the clock-gate is ungated before we 42*df730d94SMarco Felsch * access the UART register. 43*df730d94SMarco Felsch */ 44*df730d94SMarco Felsch val = mmio_read_32(IMX_CCM_BASE + imx8m_uart_info[i].ccm_reg); 45*df730d94SMarco Felsch if (DOMAIN0_RUNNING(val)) { 46*df730d94SMarco Felsch val = mmio_read_32(imx8m_uart_info[i].uart_base + UCR1); 47*df730d94SMarco Felsch if (val & UCR1_UARTEN) { 48*df730d94SMarco Felsch return imx8m_uart_info[i].uart_base; 49*df730d94SMarco Felsch } 50*df730d94SMarco Felsch } 51*df730d94SMarco Felsch } 52*df730d94SMarco Felsch 53*df730d94SMarco Felsch /* 54*df730d94SMarco Felsch * We should return an error and inform the user but we can't do it 55*df730d94SMarco Felsch * this early. 56*df730d94SMarco Felsch */ 57*df730d94SMarco Felsch return 0; 58*df730d94SMarco Felsch } 59