[PATCH v1 1/4] serial: Support OXPCIe952 aka Oxford Semiconductor Ltd Device c138 (1415:c138)

[Konrad Rzeszutek Wilk <konrad@kernel.org>]

Because they are PCIe and machine nowadys have those instead of
PCI, and they are inexpensive.

Tested with 1415:c138. Should also work on 0xc11f, 0xc11b models
of that chip.

Also on  OXPCIe200 1 Native UART 1415: 0xc40b, 0xc40f, 0xc41b,
0xc41f, 0xc42b, 0xc42f, 0xc43b, 0xc43f, 0xc44b, 0xc44f, 0xc45b
0xc45f, 0xc46b, 0xc46f, 0xc47b, 0xc47f, 0xc48b, 0xc48f, 0xc49b
0xc49f, 0xc4ab, 0xc4af, 0xc4bb, 0xc4bf, 0xc4cb, 0xc4cf

but since I don't have any of those cards this patch does not
enable it.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v1: Init for ARM and add offset to virt addr]
---
 xen/drivers/char/ns16550.c |   30 +++++++++++++++++++++++++++---
 1 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/xen/drivers/char/ns16550.c b/xen/drivers/char/ns16550.c
index 53e49a1..5dd2457 100644
--- a/xen/drivers/char/ns16550.c
+++ b/xen/drivers/char/ns16550.c
@@ -51,6 +51,7 @@ static struct ns16550 {
     int reg_width; /* Size of access to use, the registers
                     * themselves are still bytes */
     char __iomem *remapped_io_base;  /* Remapped virtual address of MMIO. */
+    unsigned int offset; /* By default zero. */
     /* UART with IRQ line: interrupt-driven I/O. */
     struct irqaction irqaction;
     u8 lsr_mask;
@@ -89,6 +90,9 @@ struct ns16550_config_mmio {
     unsigned int fifo_size;
     u8 lsr_mask;
     unsigned int max_bars;
+    unsigned int base_baud;
+    unsigned int uart_offset;
+    unsigned int first_offset;
 };
 
 
@@ -111,6 +115,19 @@ static struct ns16550_config_mmio __initdata uart_config[] =
         .lsr_mask = (UART_LSR_THRE | UART_LSR_TEMT),
         .max_bars = 1,
     },
+    /* OXPCIe952 1 Native UART  */
+    {
+        .vendor_id = 0x1415,
+        .dev_id = 0xc138,
+        .base_baud = 4000000,
+        .uart_offset = 0x200,
+        .first_offset = 0x1000,
+        .reg_width = 1,
+        .reg_shift = 0,
+        .fifo_size = 16,
+        .lsr_mask = UART_LSR_THRE,
+        .max_bars = 1, /* It can do more, but we would need more custom code.*/
+    }
 };
 #endif
 
@@ -325,11 +342,12 @@ static void __init ns16550_init_preirq(struct serial_port *port)
 #ifdef CONFIG_X86
         enum fixed_addresses idx = FIX_COM_BEGIN + (uart - ns16550_com);
 
-        set_fixmap_nocache(idx, uart->io_base);
+        set_fixmap_nocache(idx, uart->io_base + uart->offset);
         uart->remapped_io_base = (void __iomem *)fix_to_virt(idx);
-        uart->remapped_io_base += uart->io_base & ~PAGE_MASK;
+        uart->remapped_io_base += (uart->io_base + uart->offset) & ~PAGE_MASK;
 #else
-        uart->remapped_io_base = (char *)ioremap(uart->io_base, uart->io_size);
+        uart->remapped_io_base = (char *)ioremap(uart->io_base + uart->offset,
+                                                 uart->io_size);
 #endif
     }
 
@@ -701,6 +719,10 @@ pci_uart_config (struct ns16550 *uart, int skip_amt, int bar_idx)
                         uart->lsr_mask = uart_config[i].lsr_mask;
                         uart->io_base = ((u64)bar_64 << 32) |
                                         (bar & PCI_BASE_ADDRESS_MEM_MASK);
+                        uart->offset = uart_config[i].first_offset;
+                        uart->offset += bar_idx * uart_config[i].uart_offset;
+                        if ( uart_config[i].base_baud )
+                            uart->clock_hz = uart_config[i].base_baud * 16;
                         /* Set device and MMIO region read only to Dom0 */
                         uart->enable_ro = 1;
                         break;
@@ -880,6 +902,7 @@ void __init ns16550_init(int index, struct ns16550_defaults *defaults)
     uart->io_size   = 8;
     uart->reg_width = 1;
     uart->reg_shift = 0;
+    uart->offset    = 0;
 
 #ifdef HAS_PCI
     uart->enable_ro = 0;
@@ -912,6 +935,7 @@ static int __init ns16550_uart_dt_init(struct dt_device_node *dev,
     uart->stop_bits = 1;
     /* Default is no transmit FIFO. */
     uart->fifo_size = 1;
+    uart->offset    = 0;
 
     res = dt_device_get_address(dev, 0, &uart->io_base, &io_size);
     if ( res )
-- 
1.7.7.6