serial: Fix io address assign flow with Fintek PCI-to-UART Product

The original driver fixed the io address with 0xe000+idx*8,
but real io address assigned from BIOS is dynamically from
read PCI configure space 0x24, 0x20, 0x1c.

The Fintek F81504/F81508/F81512 maybe malfunction without
this patch and malfunction surely when more then 1 PCI card.

Signed-off-by: Peter Hung <hpeter+linux_kernel@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 46 insertions, 15 deletions

diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c
index 0468e15e6f10..31feeb2d0a66 100644
--- a/drivers/tty/serial/8250/8250_pci.c
+++ b/drivers/tty/serial/8250/8250_pci.c
@@ -1554,25 +1554,48 @@ static int pci_fintek_setup(struct serial_private *priv,
         unsigned long iobase;
         unsigned long ciobase = 0;
         u8 config_base;
+        u32 bar_data[3];
 
         /*
-         * We are supposed to be able to read these from the PCI config space,
-         * but the values there don't seem to match what we need to use, so
-         * just use these hard-coded values for now, as they are correct.
+         * Find each UARTs offset in PCI configuraion space
          */
         switch (idx) {
-        case 0: iobase = 0xe000; config_base = 0x40; break;
-        case 1: iobase = 0xe008; config_base = 0x48; break;
-        case 2: iobase = 0xe010; config_base = 0x50; break;
-        case 3: iobase = 0xe018; config_base = 0x58; break;
-        case 4: iobase = 0xe020; config_base = 0x60; break;
-        case 5: iobase = 0xe028; config_base = 0x68; break;
-        case 6: iobase = 0xe030; config_base = 0x70; break;
-        case 7: iobase = 0xe038; config_base = 0x78; break;
-        case 8: iobase = 0xe040; config_base = 0x80; break;
-        case 9: iobase = 0xe048; config_base = 0x88; break;
-        case 10: iobase = 0xe050; config_base = 0x90; break;
-        case 11: iobase = 0xe058; config_base = 0x98; break;
+        case 0:
+                config_base = 0x40;
+                break;
+        case 1:
+                config_base = 0x48;
+                break;
+        case 2:
+                config_base = 0x50;
+                break;
+        case 3:
+                config_base = 0x58;
+                break;
+        case 4:
+                config_base = 0x60;
+                break;
+        case 5:
+                config_base = 0x68;
+                break;
+        case 6:
+                config_base = 0x70;
+                break;
+        case 7:
+                config_base = 0x78;
+                break;
+        case 8:
+                config_base = 0x80;
+                break;
+        case 9:
+                config_base = 0x88;
+                break;
+        case 10:
+                config_base = 0x90;
+                break;
+        case 11:
+                config_base = 0x98;
+                break;
         default:
                 /* Unknown number of ports, get out of here */
                 return -EINVAL;
@@ -1583,6 +1606,14 @@ static int pci_fintek_setup(struct serial_private *priv,
                 ciobase = (int)(base + (0x8 * idx));
         }
 
+        /* Get the io address dispatch from the BIOS */
+        pci_read_config_dword(pdev, 0x24, &bar_data[0]);
+        pci_read_config_dword(pdev, 0x20, &bar_data[1]);
+        pci_read_config_dword(pdev, 0x1c, &bar_data[2]);
+
+        /* Calculate Real IO Port */
+        iobase = (bar_data[idx/4] & 0xffffffe0) + (idx % 4) * 8;
+
         dev_dbg(&pdev->dev, "%s: idx=%d iobase=0x%lx ciobase=0x%lx config_base=0x%2x\n",
                 __func__, idx, iobase, ciobase, config_base);