[ARM] 3029/1: Add HWUART support for PXA 255/26x

Patch from Matt Reimer

Adds support for HWUART on PXA 255 / 26x. This patch originally came from
http://svn.rungie.com/svn/gumstix-buildroot/trunk/sources/kernel-patches/000-gumstix-hwuart.patch
and has been tweaked by me.

Signed-off-by: Matt Reimer <mreimer@vpop.net>
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

4 files changed, 71 insertions, 2 deletions

diff --git a/arch/arm/mach-pxa/generic.c b/arch/arm/mach-pxa/generic.c
index 719b91e93fa2..218eb9671fa3 100644
--- a/arch/arm/mach-pxa/generic.c
+++ b/arch/arm/mach-pxa/generic.c
@@ -253,6 +253,10 @@ static struct platform_device stuart_device = {
         .name           = "pxa2xx-uart",
         .id             = 2,
 };
+static struct platform_device hwuart_device = {
+        .name           = "pxa2xx-uart",
+        .id             = 3,
+};
 
 static struct resource i2c_resources[] = {
         {
@@ -310,7 +314,19 @@ static struct platform_device *devices[] __initdata = {
 
 static int __init pxa_init(void)
 {
-        return platform_add_devices(devices, ARRAY_SIZE(devices));
+        int cpuid, ret;
+
+        ret = platform_add_devices(devices, ARRAY_SIZE(devices));
+        if (ret)
+                return ret;
+
+        /* Only add HWUART for PXA255/26x; PXA210/250/27x do not have it. */
+        cpuid = read_cpuid(CPUID_ID);
+        if (((cpuid >> 4) & 0xfff) == 0x2d0 ||
+            ((cpuid >> 4) & 0xfff) == 0x290)
+                ret = platform_device_register(&hwuart_device);
+
+        return ret;
 }
 
 subsys_initcall(pxa_init);
diff --git a/drivers/serial/pxa.c b/drivers/serial/pxa.c
index 90c2a86c421b..005f027e081a 100644
--- a/drivers/serial/pxa.c
+++ b/drivers/serial/pxa.c
@@ -358,6 +358,9 @@ static int serial_pxa_startup(struct uart_port *port)
         unsigned long flags;
         int retval;
 
+        if (port->line == 3) /* HWUART */
+                up->mcr |= UART_MCR_AFE;
+        else
         up->mcr = 0;
 
         /*
@@ -481,8 +484,10 @@ serial_pxa_set_termios(struct uart_port *port, struct termios *termios,
 
         if ((up->port.uartclk / quot) < (2400 * 16))
                 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR1;
-        else
+        else if ((up->port.uartclk / quot) < (230400 * 16))
                 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR8;
+        else
+                fcr = UART_FCR_ENABLE_FIFO | UART_FCR_PXAR32;
 
         /*
          * Ok, we're now changing the port state.  Do it with
@@ -772,6 +777,20 @@ static struct uart_pxa_port serial_pxa_ports[] = {
                 .ops            = &serial_pxa_pops,
                 .line           = 2,
         },
+  }, {  /* HWUART */
+        .name   = "HWUART",
+        .cken   = CKEN4_HWUART,
+        .port = {
+                .type           = PORT_PXA,
+                .iotype         = UPIO_MEM,
+                .membase        = (void *)&HWUART,
+                .mapbase        = __PREG(HWUART),
+                .irq            = IRQ_HWUART,
+                .uartclk        = 921600 * 16,
+                .fifosize       = 64,
+                .ops            = &serial_pxa_pops,
+                .line           = 3,
+        },
   }
 };
 
diff --git a/include/asm-arm/arch-pxa/pxa-regs.h b/include/asm-arm/arch-pxa/pxa-regs.h
index a6a34edec813..75f085dc9894 100644
--- a/include/asm-arm/arch-pxa/pxa-regs.h
+++ b/include/asm-arm/arch-pxa/pxa-regs.h
@@ -326,6 +326,25 @@
 #define STDLL           __REG(0x40700000)  /* Divisor Latch Low Register (DLAB = 1) (read/write) */
 #define STDLH           __REG(0x40700004)  /* Divisor Latch High Register (DLAB = 1) (read/write) */
 
+/* Hardware UART (HWUART) */
+#define HWUART          HWRBR
+#define HWRBR           __REG(0x41600000)  /* Receive Buffer Register (read only) */
+#define HWTHR           __REG(0x41600000)  /* Transmit Holding Register (write only) */
+#define HWIER           __REG(0x41600004)  /* Interrupt Enable Register (read/write) */
+#define HWIIR           __REG(0x41600008)  /* Interrupt ID Register (read only) */
+#define HWFCR           __REG(0x41600008)  /* FIFO Control Register (write only) */
+#define HWLCR           __REG(0x4160000C)  /* Line Control Register (read/write) */
+#define HWMCR           __REG(0x41600010)  /* Modem Control Register (read/write) */
+#define HWLSR           __REG(0x41600014)  /* Line Status Register (read only) */
+#define HWMSR           __REG(0x41600018)  /* Modem Status Register (read only) */
+#define HWSPR           __REG(0x4160001C)  /* Scratch Pad Register (read/write) */
+#define HWISR           __REG(0x41600020)  /* Infrared Selection Register (read/write) */
+#define HWFOR           __REG(0x41600024)  /* Receive FIFO Occupancy Register (read only) */
+#define HWABR           __REG(0x41600028)  /* Auto-Baud Control Register (read/write) */
+#define HWACR           __REG(0x4160002C)  /* Auto-Baud Count Register (read only) */
+#define HWDLL           __REG(0x41600000)  /* Divisor Latch Low Register (DLAB = 1) (read/write) */
+#define HWDLH           __REG(0x41600004)  /* Divisor Latch High Register (DLAB = 1) (read/write) */
+
 #define IER_DMAE        (1 << 7)        /* DMA Requests Enable */
 #define IER_UUE         (1 << 6)        /* UART Unit Enable */
 #define IER_NRZE        (1 << 5)        /* NRZ coding Enable */
@@ -1250,9 +1269,13 @@
 #define GPIO40_FFDTR            40      /* FFUART data terminal Ready */
 #define GPIO41_FFRTS            41      /* FFUART request to send */
 #define GPIO42_BTRXD            42      /* BTUART receive data */
+#define GPIO42_HWRXD            42      /* HWUART receive data */
 #define GPIO43_BTTXD            43      /* BTUART transmit data */
+#define GPIO43_HWTXD            43      /* HWUART transmit data */
 #define GPIO44_BTCTS            44      /* BTUART clear to send */
+#define GPIO44_HWCTS            44      /* HWUART clear to send */
 #define GPIO45_BTRTS            45      /* BTUART request to send */
+#define GPIO45_HWRTS            45      /* HWUART request to send */
 #define GPIO45_AC97_SYSCLK      45      /* AC97 System Clock */
 #define GPIO46_ICPRXD           46      /* ICP receive data */
 #define GPIO46_STRXD            46      /* STD_UART receive data */
@@ -1378,17 +1401,26 @@
 #define GPIO40_FFDTR_MD         (40 | GPIO_ALT_FN_2_OUT)
 #define GPIO41_FFRTS_MD         (41 | GPIO_ALT_FN_2_OUT)
 #define GPIO42_BTRXD_MD         (42 | GPIO_ALT_FN_1_IN)
+#define GPIO42_HWRXD_MD         (42 | GPIO_ALT_FN_3_IN)
 #define GPIO43_BTTXD_MD         (43 | GPIO_ALT_FN_2_OUT)
+#define GPIO43_HWTXD_MD         (43 | GPIO_ALT_FN_3_OUT)
 #define GPIO44_BTCTS_MD         (44 | GPIO_ALT_FN_1_IN)
+#define GPIO44_HWCTS_MD         (44 | GPIO_ALT_FN_3_IN)
 #define GPIO45_BTRTS_MD         (45 | GPIO_ALT_FN_2_OUT)
+#define GPIO45_HWRTS_MD         (45 | GPIO_ALT_FN_3_OUT)
 #define GPIO45_SYSCLK_AC97_MD           (45 | GPIO_ALT_FN_1_OUT)
 #define GPIO46_ICPRXD_MD        (46 | GPIO_ALT_FN_1_IN)
 #define GPIO46_STRXD_MD         (46 | GPIO_ALT_FN_2_IN)
 #define GPIO47_ICPTXD_MD        (47 | GPIO_ALT_FN_2_OUT)
 #define GPIO47_STTXD_MD         (47 | GPIO_ALT_FN_1_OUT)
 #define GPIO48_nPOE_MD          (48 | GPIO_ALT_FN_2_OUT)
+#define GPIO48_HWTXD_MD         (48 | GPIO_ALT_FN_1_OUT)
+#define GPIO48_nPOE_MD          (48 | GPIO_ALT_FN_2_OUT)
+#define GPIO49_HWRXD_MD         (49 | GPIO_ALT_FN_1_IN)
 #define GPIO49_nPWE_MD          (49 | GPIO_ALT_FN_2_OUT)
 #define GPIO50_nPIOR_MD         (50 | GPIO_ALT_FN_2_OUT)
+#define GPIO50_HWCTS_MD         (50 | GPIO_ALT_FN_1_IN)
+#define GPIO51_HWRTS_MD         (51 | GPIO_ALT_FN_1_OUT)
 #define GPIO51_nPIOW_MD         (51 | GPIO_ALT_FN_2_OUT)
 #define GPIO52_nPCE_1_MD        (52 | GPIO_ALT_FN_2_OUT)
 #define GPIO53_nPCE_2_MD        (53 | GPIO_ALT_FN_2_OUT)
@@ -1763,6 +1795,7 @@
 #define CKEN7_BTUART    (1 << 7)        /* BTUART Unit Clock Enable */
 #define CKEN6_FFUART    (1 << 6)        /* FFUART Unit Clock Enable */
 #define CKEN5_STUART    (1 << 5)        /* STUART Unit Clock Enable */
+#define CKEN4_HWUART    (1 << 4)        /* HWUART Unit Clock Enable */
 #define CKEN4_SSP3      (1 << 4)        /* SSP3 Unit Clock Enable */
 #define CKEN3_SSP       (1 << 3)        /* SSP Unit Clock Enable */
 #define CKEN3_SSP2      (1 << 3)        /* SSP2 Unit Clock Enable */
diff --git a/include/asm-arm/arch-pxa/uncompress.h b/include/asm-arm/arch-pxa/uncompress.h
index 4428d3eb7432..fe38090444e0 100644
--- a/include/asm-arm/arch-pxa/uncompress.h
+++ b/include/asm-arm/arch-pxa/uncompress.h
@@ -12,6 +12,7 @@
 #define FFUART          ((volatile unsigned long *)0x40100000)
 #define BTUART          ((volatile unsigned long *)0x40200000)
 #define STUART          ((volatile unsigned long *)0x40700000)
+#define HWUART          ((volatile unsigned long *)0x41600000)
 
 #define UART            FFUART