xtensa: s6000 variant

Support for the Stretch S6000 Xtensa core variant.

Signed-off-by: Johannes Weiner <jw@emlix.com>
Signed-off-by: Oskar Schirmer <os@emlix.com>
Signed-off-by: Chris Zankel <chris@zankel.net>

8 files changed, 481 insertions, 0 deletions

diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 705bb71af245..0b7cd52d8b2a 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -32,6 +32,9 @@ config GENERIC_HWEIGHT
 config GENERIC_HARDIRQS
         def_bool y
 
+config GENERIC_GPIO
+        def_bool y
+
 config ARCH_HAS_ILOG2_U32
         def_bool n
 
@@ -69,6 +72,11 @@ config XTENSA_VARIANT_DC232B
         select MMU
         help
           This variant refers to Tensilica's Diamond 232L Standard core Rev.B (LE).
+
+config XTENSA_VARIANT_S6000
+        bool "s6000 - Stretch software configurable processor"
+        select VARIANT_IRQ_SWITCH
+        select ARCH_REQUIRE_GPIOLIB
 endchoice
 
 config XTENSA_UNALIGNED_USER
diff --git a/arch/xtensa/Makefile b/arch/xtensa/Makefile
index 6d7f60e6d559..8f97a86041ad 100644
--- a/arch/xtensa/Makefile
+++ b/arch/xtensa/Makefile
@@ -15,6 +15,7 @@
 
 variant-$(CONFIG_XTENSA_VARIANT_FSF)            := fsf
 variant-$(CONFIG_XTENSA_VARIANT_DC232B)         := dc232b
+variant-$(CONFIG_XTENSA_VARIANT_S6000)          := s6000
 variant-$(CONFIG_XTENSA_VARIANT_LINUX_CUSTOM)   := custom
 
 VARIANT = $(variant-y)
diff --git a/arch/xtensa/include/asm/gpio.h b/arch/xtensa/include/asm/gpio.h
new file mode 100644
index 000000000000..0763b0763960
--- /dev/null
+++ b/arch/xtensa/include/asm/gpio.h
@@ -0,0 +1,56 @@
+/*
+ * Generic GPIO API implementation for xtensa.
+ *
+ * Stolen from x86, which is derived from the generic GPIO API for powerpc:
+ *
+ * Copyright (c) 2007-2008  MontaVista Software, Inc.
+ *
+ * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef _ASM_XTENSA_GPIO_H
+#define _ASM_XTENSA_GPIO_H
+
+#include <asm-generic/gpio.h>
+
+#ifdef CONFIG_GPIOLIB
+
+/*
+ * Just call gpiolib.
+ */
+static inline int gpio_get_value(unsigned int gpio)
+{
+        return __gpio_get_value(gpio);
+}
+
+static inline void gpio_set_value(unsigned int gpio, int value)
+{
+        __gpio_set_value(gpio, value);
+}
+
+static inline int gpio_cansleep(unsigned int gpio)
+{
+        return __gpio_cansleep(gpio);
+}
+
+/*
+ * Not implemented, yet.
+ */
+static inline int gpio_to_irq(unsigned int gpio)
+{
+        return -ENOSYS;
+}
+
+static inline int irq_to_gpio(unsigned int irq)
+{
+        return -EINVAL;
+}
+
+#endif /* CONFIG_GPIOLIB */
+
+#endif /* _ASM_XTENSA_GPIO_H */
diff --git a/arch/xtensa/variants/s6000/Makefile b/arch/xtensa/variants/s6000/Makefile
new file mode 100644
index 000000000000..03b3975468bd
--- /dev/null
+++ b/arch/xtensa/variants/s6000/Makefile
@@ -0,0 +1,3 @@
+# s6000 Makefile
+
+obj-y           += irq.o gpio.o
diff --git a/arch/xtensa/variants/s6000/gpio.c b/arch/xtensa/variants/s6000/gpio.c
new file mode 100644
index 000000000000..33a8d952934c
--- /dev/null
+++ b/arch/xtensa/variants/s6000/gpio.c
@@ -0,0 +1,71 @@
+/*
+ * s6000 gpio driver
+ *
+ * Copyright (c) 2009 emlix GmbH
+ * Authors:     Oskar Schirmer <os@emlix.com>
+ *              Johannes Weiner <jw@emlix.com>
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+
+#include <variant/hardware.h>
+
+#define S6_GPIO_DATA            0x000
+#define S6_GPIO_IS              0x404
+#define S6_GPIO_IBE             0x408
+#define S6_GPIO_IEV             0x40C
+#define S6_GPIO_IE              0x410
+#define S6_GPIO_RIS             0x414
+#define S6_GPIO_MIS             0x418
+#define S6_GPIO_IC              0x41C
+#define S6_GPIO_AFSEL           0x420
+#define S6_GPIO_DIR             0x800
+#define S6_GPIO_BANK(nr)        ((nr) * 0x1000)
+#define S6_GPIO_MASK(nr)        (4 << (nr))
+#define S6_GPIO_OFFSET(nr) \
+                (S6_GPIO_BANK((nr) >> 3) + S6_GPIO_MASK((nr) & 7))
+
+static int direction_input(struct gpio_chip *chip, unsigned int off)
+{
+        writeb(0, S6_REG_GPIO + S6_GPIO_DIR + S6_GPIO_OFFSET(off));
+        return 0;
+}
+
+static int get(struct gpio_chip *chip, unsigned int off)
+{
+        return readb(S6_REG_GPIO + S6_GPIO_DATA + S6_GPIO_OFFSET(off));
+}
+
+static int direction_output(struct gpio_chip *chip, unsigned int off, int val)
+{
+        unsigned rel = S6_GPIO_OFFSET(off);
+        writeb(~0, S6_REG_GPIO + S6_GPIO_DIR + rel);
+        writeb(val ? ~0 : 0, S6_REG_GPIO + S6_GPIO_DATA + rel);
+        return 0;
+}
+
+static void set(struct gpio_chip *chip, unsigned int off, int val)
+{
+        writeb(val ? ~0 : 0, S6_REG_GPIO + S6_GPIO_DATA + S6_GPIO_OFFSET(off));
+}
+
+static struct gpio_chip gpiochip = {
+        .owner = THIS_MODULE,
+        .direction_input = direction_input,
+        .get = get,
+        .direction_output = direction_output,
+        .set = set,
+        .base = 0,
+        .ngpio = 24,
+        .can_sleep = 0, /* no blocking io needed */
+        .exported = 0, /* no exporting to userspace */
+};
+
+static int gpio_init(void)
+{
+        return gpiochip_add(&gpiochip);
+}
+device_initcall(gpio_init);
diff --git a/arch/xtensa/variants/s6000/include/variant/hardware.h b/arch/xtensa/variants/s6000/include/variant/hardware.h
new file mode 100644
index 000000000000..5d9ba098d84a
--- /dev/null
+++ b/arch/xtensa/variants/s6000/include/variant/hardware.h
@@ -0,0 +1,259 @@
+#ifndef __XTENSA_S6000_HARDWARE_H
+#define __XTENSA_S6000_HARDWARE_H
+
+#define S6_SCLK                 1843200
+
+#define S6_MEM_REG              0x20000000
+#define S6_MEM_EFI              0x33F00000
+#define S6_MEM_PCIE_DATARAM1    0x34000000
+#define S6_MEM_XLMI             0x37F80000
+#define S6_MEM_PIF_DATARAM1     0x37FFC000
+#define S6_MEM_GMAC             0x38000000
+#define S6_MEM_I2S              0x3A000000
+#define S6_MEM_EGIB             0x3C000000
+#define S6_MEM_PCIE_CFG         0x3E000000
+#define S6_MEM_PIF_DATARAM      0x3FFE0000
+#define S6_MEM_XLMI_DATARAM     0x3FFF0000
+#define S6_MEM_DDR              0x40000000
+#define S6_MEM_PCIE_APER        0xC0000000
+#define S6_MEM_AUX              0xF0000000
+
+/* Device addresses */
+
+#define S6_REG_SCB              S6_MEM_REG
+#define S6_REG_NB               (S6_REG_SCB + 0x10000)
+#define S6_REG_LMSDMA           (S6_REG_SCB + 0x20000)
+#define S6_REG_NI               (S6_REG_SCB + 0x30000)
+#define S6_REG_NIDMA            (S6_REG_SCB + 0x40000)
+#define S6_REG_NS               (S6_REG_SCB + 0x50000)
+#define S6_REG_DDR              (S6_REG_SCB + 0x60000)
+#define S6_REG_GREG1            (S6_REG_SCB + 0x70000)
+#define S6_REG_DP               (S6_REG_SCB + 0x80000)
+#define S6_REG_DPDMA            (S6_REG_SCB + 0x90000)
+#define S6_REG_EGIB             (S6_REG_SCB + 0xA0000)
+#define S6_REG_PCIE             (S6_REG_SCB + 0xB0000)
+#define S6_REG_I2S              (S6_REG_SCB + 0xC0000)
+#define S6_REG_GMAC             (S6_REG_SCB + 0xD0000)
+#define S6_REG_HIFDMA           (S6_REG_SCB + 0xE0000)
+#define S6_REG_GREG2            (S6_REG_SCB + 0xF0000)
+
+#define S6_REG_APB              S6_REG_SCB
+#define S6_REG_UART             (S6_REG_APB + 0x0000)
+#define S6_REG_INTC             (S6_REG_APB + 0x2000)
+#define S6_REG_SPI              (S6_REG_APB + 0x3000)
+#define S6_REG_I2C              (S6_REG_APB + 0x4000)
+#define S6_REG_GPIO             (S6_REG_APB + 0x8000)
+
+/* Global register block */
+
+#define S6_GREG1_PLL_LOCKCLEAR  0x000
+#define S6_GREG1_PLL_LOCK_SYS           0
+#define S6_GREG1_PLL_LOCK_IO            1
+#define S6_GREG1_PLL_LOCK_AIM           2
+#define S6_GREG1_PLL_LOCK_DP0           3
+#define S6_GREG1_PLL_LOCK_DP2           4
+#define S6_GREG1_PLL_LOCK_DDR           5
+#define S6_GREG1_PLL_LOCKSTAT   0x004
+#define S6_GREG1_PLL_LOCKSTAT_CURLOCK   0
+#define S6_GREG1_PLL_LOCKSTAT_EVERUNLCK 8
+#define S6_GREG1_PLLSEL         0x010
+#define S6_GREG1_PLLSEL_AIM             0
+#define S6_GREG1_PLLSEL_AIM_DDR2                0
+#define S6_GREG1_PLLSEL_AIM_300MHZ              1
+#define S6_GREG1_PLLSEL_AIM_240MHZ              2
+#define S6_GREG1_PLLSEL_AIM_200MHZ              3
+#define S6_GREG1_PLLSEL_AIM_150MHZ              4
+#define S6_GREG1_PLLSEL_AIM_120MHZ              5
+#define S6_GREG1_PLLSEL_AIM_40MHZ               6
+#define S6_GREG1_PLLSEL_AIM_PLLAIMREF           7
+#define S6_GREG1_PLLSEL_AIM_MASK                7
+#define S6_GREG1_PLLSEL_DDR             8
+#define S6_GREG1_PLLSEL_DDR_HS                  0
+#define S6_GREG1_PLLSEL_DDR_333MHZ              1
+#define S6_GREG1_PLLSEL_DDR_250MHZ              2
+#define S6_GREG1_PLLSEL_DDR_200MHZ              3
+#define S6_GREG1_PLLSEL_DDR_167MHZ              4
+#define S6_GREG1_PLLSEL_DDR_100MHZ              5
+#define S6_GREG1_PLLSEL_DDR_33MHZ               6
+#define S6_GREG1_PLLSEL_DDR_PLLIOREF            7
+#define S6_GREG1_PLLSEL_DDR_MASK                7
+#define S6_GREG1_PLLSEL_GMAC            16
+#define S6_GREG1_PLLSEL_GMAC_125MHZ             0
+#define S6_GREG1_PLLSEL_GMAC_25MHZ              1
+#define S6_GREG1_PLLSEL_GMAC_2500KHZ            2
+#define S6_GREG1_PLLSEL_GMAC_EXTERN             3
+#define S6_GREG1_PLLSEL_GMAC_MASK               3
+#define S6_GREG1_PLLSEL_GMII            18
+#define S6_GREG1_PLLSEL_GMII_111MHZ             0
+#define S6_GREG1_PLLSEL_GMII_IOREF              1
+#define S6_GREG1_PLLSEL_GMII_NONE               2
+#define S6_GREG1_PLLSEL_GMII_125MHZ             3
+#define S6_GREG1_PLLSEL_GMII_MASK               3
+#define S6_GREG1_SYSUNLOCKCNT   0x020
+#define S6_GREG1_IOUNLOCKCNT    0x024
+#define S6_GREG1_AIMUNLOCKCNT   0x028
+#define S6_GREG1_DP0UNLOCKCNT   0x02C
+#define S6_GREG1_DP2UNLOCKCNT   0x030
+#define S6_GREG1_DDRUNLOCKCNT   0x034
+#define S6_GREG1_CLKBAL0        0x040
+#define S6_GREG1_CLKBAL0_LSGB           0
+#define S6_GREG1_CLKBAL0_LSPX           8
+#define S6_GREG1_CLKBAL0_MEMDO          16
+#define S6_GREG1_CLKBAL0_HSXT1          24
+#define S6_GREG1_CLKBAL1        0x044
+#define S6_GREG1_CLKBAL1_HSISEF         0
+#define S6_GREG1_CLKBAL1_HSNI           8
+#define S6_GREG1_CLKBAL1_HSNS           16
+#define S6_GREG1_CLKBAL1_HSISEFCFG      24
+#define S6_GREG1_CLKBAL2        0x048
+#define S6_GREG1_CLKBAL2_LSNB           0
+#define S6_GREG1_CLKBAL2_LSSB           8
+#define S6_GREG1_CLKBAL2_LSREST         24
+#define S6_GREG1_CLKBAL3        0x04C
+#define S6_GREG1_CLKBAL3_ISEFXAD        0
+#define S6_GREG1_CLKBAL3_ISEFLMS        8
+#define S6_GREG1_CLKBAL3_ISEFISEF       16
+#define S6_GREG1_CLKBAL3_DDRDD          24
+#define S6_GREG1_CLKBAL4        0x050
+#define S6_GREG1_CLKBAL4_DDRDP          0
+#define S6_GREG1_CLKBAL4_DDRDO          8
+#define S6_GREG1_CLKBAL4_DDRNB          16
+#define S6_GREG1_CLKBAL4_DDRLMS         24
+#define S6_GREG1_BLOCKENA       0x100
+#define S6_GREG1_BLOCK_DDR              0
+#define S6_GREG1_BLOCK_DP               1
+#define S6_GREG1_BLOCK_NSNI             2
+#define S6_GREG1_BLOCK_PCIE             3
+#define S6_GREG1_BLOCK_GMAC             4
+#define S6_GREG1_BLOCK_I2S              5
+#define S6_GREG1_BLOCK_EGIB             6
+#define S6_GREG1_BLOCK_SB               7
+#define S6_GREG1_BLOCK_XT1              8
+#define S6_GREG1_CLKGATE        0x104
+#define S6_GREG1_BGATE_AIMNORTH         9
+#define S6_GREG1_BGATE_AIMEAST          10
+#define S6_GREG1_BGATE_AIMWEST          11
+#define S6_GREG1_BGATE_AIMSOUTH         12
+#define S6_GREG1_CHIPRES        0x108
+#define S6_GREG1_CHIPRES_SOFTRES        0
+#define S6_GREG1_CHIPRES_LOSTLOCK       1
+#define S6_GREG1_RESETCAUSE     0x10C
+#define S6_GREG1_RESETCAUSE_RESETN      0
+#define S6_GREG1_RESETCAUSE_GLOBAL      1
+#define S6_GREG1_RESETCAUSE_WDOGTIMER   2
+#define S6_GREG1_RESETCAUSE_SWCHIP      3
+#define S6_GREG1_RESETCAUSE_PLLSYSLOSS  4
+#define S6_GREG1_RESETCAUSE_PCIE        5
+#define S6_GREG1_RESETCAUSE_CREATEDGLOB 6
+#define S6_GREG1_REFCLOCKCNT    0x110
+#define S6_GREG1_RESETTIMER     0x114
+#define S6_GREG1_NMITIMER       0x118
+#define S6_GREG1_GLOBAL_TIMER   0x11C
+#define S6_GREG1_TIMER0         0x180
+#define S6_GREG1_TIMER1         0x184
+#define S6_GREG1_UARTCLOCKSEL   0x204
+#define S6_GREG1_CHIPVERSPACKG  0x208
+#define S6_GREG1_CHIPVERSPACKG_CHIPVID  0
+#define S6_GREG1_CHIPVERSPACKG_PACKSEL  8
+#define S6_GREG1_ONDIETERMCTRL  0x20C
+#define S6_GREG1_ONDIETERMCTRL_WEST     0
+#define S6_GREG1_ONDIETERMCTRL_NORTH    2
+#define S6_GREG1_ONDIETERMCTRL_EAST     4
+#define S6_GREG1_ONDIETERMCTRL_SOUTH    6
+#define S6_GREG1_ONDIETERMCTRL_NONE             0
+#define S6_GREG1_ONDIETERMCTRL_75OHM            2
+#define S6_GREG1_ONDIETERMCTRL_MASK             3
+#define S6_GREG1_BOOT_CFG0      0x210
+#define S6_GREG1_BOOT_CFG0_AIMSTRONG    1
+#define S6_GREG1_BOOT_CFG0_MINIBOOTDL   2
+#define S6_GREG1_BOOT_CFG0_OCDGPIO8SET  5
+#define S6_GREG1_BOOT_CFG0_OCDGPIOENA   6
+#define S6_GREG1_BOOT_CFG0_DOWNSTREAM   7
+#define S6_GREG1_BOOT_CFG0_PLLSYSDIV    8
+#define S6_GREG1_BOOT_CFG0_PLLSYSDIV_300MHZ     1
+#define S6_GREG1_BOOT_CFG0_PLLSYSDIV_240MHZ     2
+#define S6_GREG1_BOOT_CFG0_PLLSYSDIV_200MHZ     3
+#define S6_GREG1_BOOT_CFG0_PLLSYSDIV_150MHZ     4
+#define S6_GREG1_BOOT_CFG0_PLLSYSDIV_120MHZ     5
+#define S6_GREG1_BOOT_CFG0_PLLSYSDIV_40MHZ      6
+#define S6_GREG1_BOOT_CFG0_PLLSYSDIV_MASK       7
+#define S6_GREG1_BOOT_CFG0_BALHSLMS     12
+#define S6_GREG1_BOOT_CFG0_BALHSNB      18
+#define S6_GREG1_BOOT_CFG0_BALHSXAD     24
+#define S6_GREG1_BOOT_CFG1      0x214
+#define S6_GREG1_BOOT_CFG1_PCIE1LANE    1
+#define S6_GREG1_BOOT_CFG1_MPLLPRESCALE 2
+#define S6_GREG1_BOOT_CFG1_MPLLNCY      4
+#define S6_GREG1_BOOT_CFG1_MPLLNCY5     9
+#define S6_GREG1_BOOT_CFG1_BALHSREST    14
+#define S6_GREG1_BOOT_CFG1_BALHSPSMEMS  20
+#define S6_GREG1_BOOT_CFG1_BALLSGI      26
+#define S6_GREG1_BOOT_CFG2      0x218
+#define S6_GREG1_BOOT_CFG2_PEID         0
+#define S6_GREG1_BOOT_CFG3      0x21C
+#define S6_GREG1_DRAMBUSYHOLDOF 0x220
+#define S6_GREG1_DRAMBUSYHOLDOF_XT0     0
+#define S6_GREG1_DRAMBUSYHOLDOF_XT1     4
+#define S6_GREG1_DRAMBUSYHOLDOF_XT_MASK         7
+#define S6_GREG1_PCIEBAR1SIZE   0x224
+#define S6_GREG1_PCIEBAR2SIZE   0x228
+#define S6_GREG1_PCIEVENDOR     0x22C
+#define S6_GREG1_PCIEDEVICE     0x230
+#define S6_GREG1_PCIEREV        0x234
+#define S6_GREG1_PCIECLASS      0x238
+#define S6_GREG1_XT1DCACHEMISS  0x240
+#define S6_GREG1_XT1ICACHEMISS  0x244
+#define S6_GREG1_HWSEMAPHORE(n) (0x400 + 4 * (n))
+#define S6_GREG1_HWSEMAPHORE_NB         16
+
+/* peripheral interrupt numbers */
+
+#define S6_INTC_GPIO(n)                 (n)             /* 0..3 */
+#define S6_INTC_I2C                     4
+#define S6_INTC_SPI                     5
+#define S6_INTC_NB_ERR                  6
+#define S6_INTC_DMA_LMSERR              7
+#define S6_INTC_DMA_LMSLOWWMRK(n)       (8 + (n))       /* 0..11 */
+#define S6_INTC_DMA_LMSPENDCNT(n)       (20 + (n))      /* 0..11 */
+#define S6_INTC_DMA HOSTLOWWMRK(n)      (32 + (n))      /* 0..6 */
+#define S6_INTC_DMA_HOSTPENDCNT(n)      (39 + (n))      /* 0..6 */
+#define S6_INTC_DMA_HOSTERR             46
+#define S6_INTC_UART(n)                 (47 + (n))      /* 0..1 */
+#define S6_INTC_XAD                     49
+#define S6_INTC_NI_ERR                  50
+#define S6_INTC_NI_INFIFOFULL           51
+#define S6_INTC_DMA_NIERR               52
+#define S6_INTC_DMA_NILOWWMRK(n)        (53 + (n))      /* 0..3 */
+#define S6_INTC_DMA_NIPENDCNT(n)        (57 + (n))      /* 0..3 */
+#define S6_INTC_DDR                     61
+#define S6_INTC_NS_ERR                  62
+#define S6_INTC_EFI_CFGERR              63
+#define S6_INTC_EFI_ISEFTEST            64
+#define S6_INTC_EFI_WRITEERR            65
+#define S6_INTC_NMI_TIMER               66
+#define S6_INTC_PLLLOCK_SYS             67
+#define S6_INTC_PLLLOCK_IO              68
+#define S6_INTC_PLLLOCK_AIM             69
+#define S6_INTC_PLLLOCK_DP0             70
+#define S6_INTC_PLLLOCK_DP2             71
+#define S6_INTC_I2S_ERR                 72
+#define S6_INTC_GMAC_STAT               73
+#define S6_INTC_GMAC_ERR                74
+#define S6_INTC_GIB_ERR                 75
+#define S6_INTC_PCIE_ERR                76
+#define S6_INTC_PCIE_MSI(n)             (77 + (n))      /* 0..3 */
+#define S6_INTC_PCIE_INTA               81
+#define S6_INTC_PCIE_INTB               82
+#define S6_INTC_PCIE_INTC               83
+#define S6_INTC_PCIE_INTD               84
+#define S6_INTC_SW(n)                   (85 + (n))      /* 0..9 */
+#define S6_INTC_SW_ENABLE(n)            (85 + 256 + (n))
+#define S6_INTC_DMA_DP_ERR              95
+#define S6_INTC_DMA_DPLOWWMRK(n)        (96 + (n))      /* 0..3 */
+#define S6_INTC_DMA_DPPENDCNT(n)        (100 + (n))     /* 0..3 */
+#define S6_INTC_DMA_DPTERMCNT(n)        (104 + (n))     /* 0..3 */
+#define S6_INTC_TIMER0                  108
+#define S6_INTC_TIMER1                  109
+#define S6_INTC_DMA_HOSTTERMCNT(n)      (110 + (n))     /* 0..6 */
+
+#endif /* __XTENSA_S6000_HARDWARE_H */
diff --git a/arch/xtensa/variants/s6000/include/variant/irq.h b/arch/xtensa/variants/s6000/include/variant/irq.h
new file mode 100644
index 000000000000..fa031cb0acc4
--- /dev/null
+++ b/arch/xtensa/variants/s6000/include/variant/irq.h
@@ -0,0 +1,9 @@
+#ifndef __XTENSA_S6000_IRQ_H
+#define __XTENSA_S6000_IRQ_H
+
+#define NO_IRQ          (-1)
+
+extern void variant_irq_enable(unsigned int irq);
+extern void variant_irq_disable(unsigned int irq);
+
+#endif /* __XTENSA_S6000_IRQ_H */
diff --git a/arch/xtensa/variants/s6000/irq.c b/arch/xtensa/variants/s6000/irq.c
new file mode 100644
index 000000000000..6651e3285fcf
--- /dev/null
+++ b/arch/xtensa/variants/s6000/irq.c
@@ -0,0 +1,74 @@
+/*
+ * s6000 irq crossbar
+ *
+ * Copyright (c) 2009 emlix GmbH
+ * Authors:     Johannes Weiner <jw@emlix.com>
+ *              Oskar Schirmer <os@emlix.com>
+ */
+#include <linux/io.h>
+#include <asm/irq.h>
+#include <variant/hardware.h>
+
+/* S6_REG_INTC */
+#define INTC_STATUS     0x000
+#define INTC_RAW        0x010
+#define INTC_STATUS_AG  0x100
+#define INTC_CFG(n)     (0x200 + 4 * (n))
+
+/*
+ * The s6000 has a crossbar that multiplexes interrupt output lines
+ * from the peripherals to input lines on the xtensa core.
+ *
+ * We leave the mapping decisions to the platform as it depends on the
+ * actually connected peripherals which distribution makes sense.
+ */
+extern const signed char *platform_irq_mappings[NR_IRQS];
+
+static unsigned long scp_to_intc_enable[] = {
+#define TO_INTC_ENABLE(n)       (((n) << 1) + 1)
+        TO_INTC_ENABLE(0),
+        TO_INTC_ENABLE(1),
+        TO_INTC_ENABLE(2),
+        TO_INTC_ENABLE(3),
+        TO_INTC_ENABLE(4),
+        TO_INTC_ENABLE(5),
+        TO_INTC_ENABLE(6),
+        TO_INTC_ENABLE(7),
+        TO_INTC_ENABLE(8),
+        TO_INTC_ENABLE(9),
+        TO_INTC_ENABLE(10),
+        TO_INTC_ENABLE(11),
+        TO_INTC_ENABLE(12),
+        -1,
+        -1,
+        TO_INTC_ENABLE(13),
+        -1,
+        TO_INTC_ENABLE(14),
+        -1,
+        TO_INTC_ENABLE(15),
+#undef  TO_INTC_ENABLE
+};
+
+static void irq_set(unsigned int irq, int enable)
+{
+        unsigned long en;
+        const signed char *m = platform_irq_mappings[irq];
+
+        if (!m)
+                return;
+        en = enable ? scp_to_intc_enable[irq] : 0;
+        while (*m >= 0) {
+                writel(en, S6_REG_INTC + INTC_CFG(*m));
+                m++;
+        }
+}
+
+void variant_irq_enable(unsigned int irq)
+{
+        irq_set(irq, 1);
+}
+
+void variant_irq_disable(unsigned int irq)
+{
+        irq_set(irq, 0);
+}