oxpcie_early.c

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/* SPDX-License-Identifier: GPL-2.0-only */
 
#include <stdint.h>
#include <stddef.h>
#include <device/pci_ops.h>
#include <console/uart.h>
#include <device/pci.h>
#include <device/pci_def.h>
 
static unsigned int oxpcie_present;
static DEVTREE_CONST u32 uart0_base = CONFIG_EARLY_PCI_MMIO_BASE + 0x1000;
 
int pci_early_device_probe(u8 bus, u8 dev, u32 mmio_base)
{
        pci_devfn_t device = PCI_DEV(bus, dev, 0);
 
        u32 id = pci_s_read_config32(device, PCI_VENDOR_ID);
        switch (id) {
        case 0xc1181415: /* e.g. Startech PEX1S1PMINI function 0 */
                /* On this device function 0 is the parallel port, and
                 * function 3 is the serial port. So let's go look for
                 * the UART.
                 */
                device = PCI_DEV(bus, dev, 3);
                id = pci_s_read_config32(device, PCI_VENDOR_ID);
                if (id != 0xc11b1415)
                        return -1;
                break;
        case 0xc11b1415: /* e.g. Startech PEX1S1PMINI function 3 */
        case 0xc1581415: /* e.g. Startech MPEX2S952 */
                break;
        default:
                /* No UART here. */
                return -1;
        }
 
        /* Sanity-check, we assume fixed location. */
        if (mmio_base != CONFIG_EARLY_PCI_MMIO_BASE)
                return -1;
 
        /* Setup base address on device */
        pci_s_write_config32(device, PCI_BASE_ADDRESS_0, mmio_base);
 
        /* Enable memory on device */
        u16 reg16 = pci_s_read_config16(device, PCI_COMMAND);
        reg16 |= PCI_COMMAND_MEMORY;
        pci_s_write_config16(device, PCI_COMMAND, reg16);
 
        oxpcie_present = 1;
        return 0;
}
 
static int oxpcie_uart_active(void)
{
        return oxpcie_present;
}
 
uintptr_t uart_platform_base(unsigned int idx)
{
        if ((idx < 8) && oxpcie_uart_active())
                return uart0_base + idx * 0x200;
        return 0;
}
 
void oxford_remap(u32 new_base)
{
#if ENV_RAMSTAGE
        uart0_base = new_base + 0x1000;
#endif
}
 
unsigned int uart_platform_refclk(void)
{
        return 62500000;
}