src/soc/intel/denverton_ns/uart.c

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2
   3 /*
   4  * The sole purpose of this driver is to avoid BAR to be changed during
   5  * resource allocation. Since configuration space is just 32 bytes it
   6  * shouldn't cause any fragmentation.
   7  */
   8
   9 #include <console/uart.h>
  10 #include <device/device.h>
  11 #include <device/pci.h>
  12 #include <device/pci_ops.h>
  13 #include <device/pci_ids.h>
  14 #include <soc/pci_devs.h>
  15 #include <console/console.h>
  16 #include <soc/uart.h>
  17 #include <fsp/api.h>
  18
  19 static void dnv_ns_uart_read_resources(struct device *dev)
  20 {
  21         /* read resources to be visible in the log*/
  22         pci_dev_read_resources(dev);
  23         if (!CONFIG(LEGACY_UART_MODE))
  24                 return;
  25         struct resource *res = probe_resource(dev, PCI_BASE_ADDRESS_0);
  26         if (res == NULL)
  27                 return;
  28         res->size = 0x8;
  29         res->flags = IORESOURCE_IO | IORESOURCE_ASSIGNED | IORESOURCE_FIXED;
  30         /* Do not configure membar */
  31         res = probe_resource(dev, PCI_BASE_ADDRESS_1);
  32         if (res != NULL)
  33                 res->flags = 0;
  34         compact_resources(dev);
  35 }
  36
  37 static struct device_operations uart_ops = {
  38         .read_resources = dnv_ns_uart_read_resources,
  39         .set_resources = pci_dev_set_resources,
  40         .enable_resources = pci_dev_enable_resources,
  41         .init = pci_dev_init,
  42 };
  43
  44 static const struct pci_driver uart_driver __pci_driver = {
  45         .ops = &uart_ops,
  46         .vendor = PCI_VID_INTEL,
  47         .device = PCI_DID_INTEL_DNV_HSUART
  48 };
  49
  50 static void hide_hsuarts(void)
  51 {
  52         int i;
  53         printk(BIOS_DEBUG, "HIDING HSUARTs.\n");
  54         /* There is a hardware requirement to hide functions starting from the
  55            last one. */
  56         for (i = DENVERTON_UARTS_TO_INI - 1; i >= 0; i--) {
  57                 struct device *uart_dev;
  58                 uart_dev = pcidev_on_root(HSUART_DEV, i);
  59                 if (uart_dev == NULL)
  60                         continue;
  61                 pci_or_config32(uart_dev, PCI_FUNC_RDCFG_HIDE, 1);
  62         }
  63 }
  64
  65 /* Hide HSUART PCI device very last when FSP no longer needs it */
  66 void platform_fsp_notify_status(enum fsp_notify_phase phase)
  67 {
  68         if (phase != END_OF_FIRMWARE)
  69                 return;
  70         if (CONFIG(LEGACY_UART_MODE))
  71                 hide_hsuarts();
  72 }