This patch adds EISA support for non PCI RMs (RM200 and RM400-xxx). The
major part is the splitting of the EISA and onboard ISA of the RM200,
which makes the EISA bus on the RM200 look like on other RMs.
Signed-off-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
---
arch/mips/sni/Makefile | 1 +
arch/mips/sni/a20r.c | 2 +-
arch/mips/sni/eisa.c | 52 ++++++++
arch/mips/sni/rm200.c | 322 ++++++++++++++++++++++++++++++++++++++++++++++--
4 files changed, 366 insertions(+), 11 deletions(-)
diff --git a/arch/mips/sni/Makefile b/arch/mips/sni/Makefile
index 3a99cd6..8f4e30a 100644
--- a/arch/mips/sni/Makefile
+++ b/arch/mips/sni/Makefile
@@ -4,5 +4,6 @@
obj-y += irq.o reset.o setup.o a20r.o rm200.o pcimt.o pcit.o time.o
obj-$(CONFIG_CPU_BIG_ENDIAN) += sniprom.o
+obj-$(CONFIG_EISA) += eisa.o
EXTRA_CFLAGS += -Werror
diff --git a/arch/mips/sni/a20r.c b/arch/mips/sni/a20r.c
index b746075..2eaaa5e 100644
--- a/arch/mips/sni/a20r.c
+++ b/arch/mips/sni/a20r.c
@@ -231,9 +231,9 @@ static int __init snirm_a20r_setup_devinit(void)
platform_device_register(&sc26xx_pdev);
platform_device_register(&a20r_serial8250_device);
platform_device_register(&a20r_ds1216_device);
+ sni_eisa_root_init();
break;
}
-
return 0;
}
diff --git a/arch/mips/sni/eisa.c b/arch/mips/sni/eisa.c
new file mode 100644
index 0000000..2fd2412
--- /dev/null
+++ b/arch/mips/sni/eisa.c
@@ -0,0 +1,52 @@
+/*
+ * Virtual EISA root driver.
+ * Acts as a placeholder if we don't have a proper EISA bridge.
+ *
+ * (C) 2003 Marc Zyngier <maz@xxxxxxxxxxxxxxxxxxx>
+ * modified for SNI usage by Thomas Bogendoerfer
+ *
+ * This code is released under the GPL version 2.
+ */
+
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/eisa.h>
+#include <linux/init.h>
+
+/* The default EISA device parent (virtual root device).
+ * Now use a platform device, since that's the obvious choice. */
+
+static struct platform_device eisa_root_dev = {
+ .name = "eisa",
+ .id = 0,
+};
+
+static struct eisa_root_device eisa_bus_root = {
+ .dev = &eisa_root_dev.dev,
+ .bus_base_addr = 0,
+ .res = &ioport_resource,
+ .slots = EISA_MAX_SLOTS,
+ .dma_mask = 0xffffffff,
+ .force_probe = 1,
+};
+
+int __init sni_eisa_root_init(void)
+{
+ int r;
+
+ r = platform_device_register(&eisa_root_dev);
+ if (!r)
+ return r;
+
+ eisa_root_dev.dev.driver_data = &eisa_bus_root;
+
+ if (eisa_root_register(&eisa_bus_root)) {
+ /* A real bridge may have been registered before
+ * us. So quietly unregister. */
+ platform_device_unregister(&eisa_root_dev);
+ return -1;
+ }
+ return 0;
+}
+
+
diff --git a/arch/mips/sni/rm200.c b/arch/mips/sni/rm200.c
index 67b061e..0a3ae99 100644
--- a/arch/mips/sni/rm200.c
+++ b/arch/mips/sni/rm200.c
@@ -5,30 +5,36 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
- * Copyright (C) 2006 Thomas Bogendoerfer (tsbogend@xxxxxxxxxxxxxxxx)
+ * Copyright (C) 2006,2007 Thomas Bogendoerfer (tsbogend@xxxxxxxxxxxxxxxx)
+ *
+ * i8259 parts ripped out of arch/mips/kernel/i8259.c
*/
+#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/serial_8250.h>
+#include <linux/io.h>
#include <asm/sni.h>
#include <asm/time.h>
#include <asm/irq_cpu.h>
-#define PORT(_base,_irq) \
+#define RM200_I8259A_IRQ_BASE 32
+
+#define MEMPORT(_base,_irq) \
{ \
- .iobase = _base, \
+ .mapbase = _base, \
.irq = _irq, \
.uartclk = 1843200, \
- .iotype = UPIO_PORT, \
- .flags = UPF_BOOT_AUTOCONF, \
+ .iotype = UPIO_MEM, \
+ .flags = UPF_BOOT_AUTOCONF|UPF_IOREMAP, \
}
static struct plat_serial8250_port rm200_data[] = {
- PORT(0x3f8, 4),
- PORT(0x2f8, 3),
+ MEMPORT(0x160003f8, RM200_I8259A_IRQ_BASE + 4),
+ MEMPORT(0x160002f8, RM200_I8259A_IRQ_BASE + 3),
{ },
};
@@ -112,12 +118,308 @@ static int __init snirm_setup_devinit(void)
platform_device_register(&rm200_ds1216_device);
platform_device_register(&snirm_82596_rm200_pdev);
platform_device_register(&snirm_53c710_rm200_pdev);
+ sni_eisa_root_init();
}
return 0;
}
device_initcall(snirm_setup_devinit);
+/*
+ * RM200 has an ISA and an EISA bus. The iSA bus is only used
+ * for onboard devices and also has twi i8259 PICs. Since these
+ * PICs are no accessible via inb/outb the following code uses
+ * readb/writeb to access them
+ */
+
+DEFINE_SPINLOCK(sni_rm200_i8259A_lock);
+#define PIC_CMD 0x00
+#define PIC_IMR 0x01
+#define PIC_ISR PIC_CMD
+#define PIC_POLL PIC_ISR
+#define PIC_OCW3 PIC_ISR
+
+/* i8259A PIC related value */
+#define PIC_CASCADE_IR 2
+#define MASTER_ICW4_DEFAULT 0x01
+#define SLAVE_ICW4_DEFAULT 0x01
+
+/*
+ * This contains the irq mask for both 8259A irq controllers,
+ */
+static unsigned int rm200_cached_irq_mask = 0xffff;
+static __iomem u8 *rm200_pic_master;
+static __iomem u8 *rm200_pic_slave;
+
+#define cached_master_mask (rm200_cached_irq_mask)
+#define cached_slave_mask (rm200_cached_irq_mask >> 8)
+
+static void sni_rm200_disable_8259A_irq(unsigned int irq)
+{
+ unsigned int mask;
+ unsigned long flags;
+
+ irq -= RM200_I8259A_IRQ_BASE;
+ mask = 1 << irq;
+ spin_lock_irqsave(&sni_rm200_i8259A_lock, flags);
+ rm200_cached_irq_mask |= mask;
+ if (irq & 8)
+ writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR);
+ else
+ writeb(cached_master_mask, rm200_pic_master + PIC_IMR);
+ spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags);
+}
+
+static void sni_rm200_enable_8259A_irq(unsigned int irq)
+{
+ unsigned int mask;
+ unsigned long flags;
+
+ irq -= RM200_I8259A_IRQ_BASE;
+ mask = ~(1 << irq);
+ spin_lock_irqsave(&sni_rm200_i8259A_lock, flags);
+ rm200_cached_irq_mask &= mask;
+ if (irq & 8)
+ writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR);
+ else
+ writeb(cached_master_mask, rm200_pic_master + PIC_IMR);
+ spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags);
+}
+
+static inline int sni_rm200_i8259A_irq_real(unsigned int irq)
+{
+ int value;
+ int irqmask = 1 << irq;
+
+ if (irq < 8) {
+ writeb(0x0B, rm200_pic_master + PIC_CMD);
+ value = readb(rm200_pic_master + PIC_CMD) & irqmask;
+ writeb(0x0A, rm200_pic_master + PIC_CMD);
+ return value;
+ }
+ writeb(0x0B, rm200_pic_slave + PIC_CMD); /* ISR register */
+ value = readb(rm200_pic_slave + PIC_CMD) & (irqmask >> 8);
+ writeb(0x0A, rm200_pic_slave + PIC_CMD);
+ return value;
+}
+
+/*
+ * Careful! The 8259A is a fragile beast, it pretty
+ * much _has_ to be done exactly like this (mask it
+ * first, _then_ send the EOI, and the order of EOI
+ * to the two 8259s is important!
+ */
+void sni_rm200_mask_and_ack_8259A(unsigned int irq)
+{
+ unsigned int irqmask;
+ unsigned long flags;
+
+ irq -= RM200_I8259A_IRQ_BASE;
+ irqmask = 1 << irq;
+ spin_lock_irqsave(&sni_rm200_i8259A_lock, flags);
+ /*
+ * Lightweight spurious IRQ detection. We do not want
+ * to overdo spurious IRQ handling - it's usually a sign
+ * of hardware problems, so we only do the checks we can
+ * do without slowing down good hardware unnecessarily.
+ *
+ * Note that IRQ7 and IRQ15 (the two spurious IRQs
+ * usually resulting from the 8259A-1|2 PICs) occur
+ * even if the IRQ is masked in the 8259A. Thus we
+ * can check spurious 8259A IRQs without doing the
+ * quite slow i8259A_irq_real() call for every IRQ.
+ * This does not cover 100% of spurious interrupts,
+ * but should be enough to warn the user that there
+ * is something bad going on ...
+ */
+ if (rm200_cached_irq_mask & irqmask)
+ goto spurious_8259A_irq;
+ rm200_cached_irq_mask |= irqmask;
+
+handle_real_irq:
+ if (irq & 8) {
+ readb(rm200_pic_slave + PIC_IMR);
+ writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR);
+ writeb(0x60+(irq & 7), rm200_pic_slave + PIC_CMD);
+ writeb(0x60+PIC_CASCADE_IR, rm200_pic_master + PIC_CMD);
+ } else {
+ readb(rm200_pic_master + PIC_IMR);
+ writeb(cached_master_mask, rm200_pic_master + PIC_IMR);
+ writeb(0x60+irq, rm200_pic_master + PIC_CMD);
+ }
+ spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags);
+ return;
+
+spurious_8259A_irq:
+ /*
+ * this is the slow path - should happen rarely.
+ */
+ if (sni_rm200_i8259A_irq_real(irq))
+ /*
+ * oops, the IRQ _is_ in service according to the
+ * 8259A - not spurious, go handle it.
+ */
+ goto handle_real_irq;
+
+ {
+ static int spurious_irq_mask;
+ /*
+ * At this point we can be sure the IRQ is spurious,
+ * lets ACK and report it. [once per IRQ]
+ */
+ if (!(spurious_irq_mask & irqmask)) {
+ printk(KERN_DEBUG
+ "spurious RM200 8259A interrupt: IRQ%d.\n", irq);
+ spurious_irq_mask |= irqmask;
+ }
+ atomic_inc(&irq_err_count);
+ /*
+ * Theoretically we do not have to handle this IRQ,
+ * but in Linux this does not cause problems and is
+ * simpler for us.
+ */
+ goto handle_real_irq;
+ }
+}
+
+static struct irq_chip sni_rm200_i8259A_chip = {
+ .name = "RM200-XT-PIC",
+ .mask = sni_rm200_disable_8259A_irq,
+ .unmask = sni_rm200_enable_8259A_irq,
+ .mask_ack = sni_rm200_mask_and_ack_8259A,
+};
+
+/*
+ * Do the traditional i8259 interrupt polling thing. This is for the few
+ * cases where no better interrupt acknowledge method is available and we
+ * absolutely must touch the i8259.
+ */
+static inline int sni_rm200_i8259_irq(void)
+{
+ int irq;
+
+ spin_lock(&sni_rm200_i8259A_lock);
+
+ /* Perform an interrupt acknowledge cycle on controller 1. */
+ writeb(0x0C, rm200_pic_master + PIC_CMD); /* prepare for poll */
+ irq = readb(rm200_pic_master + PIC_CMD) & 7;
+ if (irq == PIC_CASCADE_IR) {
+ /*
+ * Interrupt is cascaded so perform interrupt
+ * acknowledge on controller 2.
+ */
+ writeb(0x0C, rm200_pic_slave + PIC_CMD); /* prepare for poll */
+ irq = (readb(rm200_pic_slave + PIC_CMD) & 7) + 8;
+ }
+
+ if (unlikely(irq == 7)) {
+ /*
+ * This may be a spurious interrupt.
+ *
+ * Read the interrupt status register (ISR). If the most
+ * significant bit is not set then there is no valid
+ * interrupt.
+ */
+ writeb(0x0B, rm200_pic_master + PIC_ISR); /* ISR register */
+ if (~readb(rm200_pic_master + PIC_ISR) & 0x80)
+ irq = -1;
+ }
+
+ spin_unlock(&sni_rm200_i8259A_lock);
+
+ return likely(irq >= 0) ? irq + RM200_I8259A_IRQ_BASE : irq;
+}
+
+void sni_rm200_init_8259A(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&sni_rm200_i8259A_lock, flags);
+
+ writeb(0xff, rm200_pic_master + PIC_IMR);
+ writeb(0xff, rm200_pic_slave + PIC_IMR);
+
+ writeb(0x11, rm200_pic_master + PIC_CMD);
+ writeb(0, rm200_pic_master + PIC_IMR);
+ writeb(1U << PIC_CASCADE_IR, rm200_pic_master + PIC_IMR);
+ writeb(MASTER_ICW4_DEFAULT, rm200_pic_master + PIC_IMR);
+ writeb(0x11, rm200_pic_slave + PIC_CMD);
+ writeb(8, rm200_pic_slave + PIC_IMR);
+ writeb(PIC_CASCADE_IR, rm200_pic_slave + PIC_IMR);
+ writeb(SLAVE_ICW4_DEFAULT, rm200_pic_slave + PIC_IMR);
+ udelay(100); /* wait for 8259A to initialize */
+
+ writeb(cached_master_mask, rm200_pic_master + PIC_IMR);
+ writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR);
+
+ spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags);
+}
+
+/*
+ * IRQ2 is cascade interrupt to second interrupt controller
+ */
+static struct irqaction sni_rm200_irq2 = {
+ no_action, 0, CPU_MASK_NONE, "cascade", NULL, NULL
+};
+
+static struct resource sni_rm200_pic1_resource = {
+ .name = "onboard ISA pic1",
+ .start = 0x16000020,
+ .end = 0x16000023,
+ .flags = IORESOURCE_BUSY
+};
+
+static struct resource sni_rm200_pic2_resource = {
+ .name = "onboard ISA pic2",
+ .start = 0x160000a0,
+ .end = 0x160000a3,
+ .flags = IORESOURCE_BUSY
+};
+
+/* ISA irq handler */
+static irqreturn_t sni_rm200_i8259A_irq_handler(int dummy, void *p)
+{
+ int irq;
+
+ irq = sni_rm200_i8259_irq();
+ if (unlikely(irq < 0))
+ return IRQ_NONE;
+
+ do_IRQ(irq);
+ return IRQ_HANDLED;
+}
+
+struct irqaction sni_rm200_i8259A_irq = {
+ .handler = sni_rm200_i8259A_irq_handler,
+ .name = "onboard ISA",
+ .flags = IRQF_SHARED
+};
+
+void __init sni_rm200_i8259_irqs(void)
+{
+ int i;
+
+ rm200_pic_master = ioremap_nocache(0x16000020, 4);
+ if (!rm200_pic_master)
+ return;
+ rm200_pic_slave = ioremap_nocache(0x160000a0, 4);
+ if (!rm200_pic_master) {
+ iounmap(rm200_pic_master);
+ return;
+ }
+
+ insert_resource(&iomem_resource, &sni_rm200_pic1_resource);
+ insert_resource(&iomem_resource, &sni_rm200_pic2_resource);
+
+ sni_rm200_init_8259A();
+
+ for (i = RM200_I8259A_IRQ_BASE; i < RM200_I8259A_IRQ_BASE + 16; i++)
+ set_irq_chip_and_handler(i, &sni_rm200_i8259A_chip,
+ handle_level_irq);
+
+ setup_irq(RM200_I8259A_IRQ_BASE + PIC_CASCADE_IR, &sni_rm200_irq2);
+}
+
#define SNI_RM200_INT_STAT_REG 0xbc000000
#define SNI_RM200_INT_ENA_REG 0xbc080000
@@ -181,17 +483,17 @@ void __init sni_rm200_irq_init(void)
* (volatile u8 *)SNI_RM200_INT_ENA_REG = 0x1f;
+ sni_rm200_i8259_irqs();
mips_cpu_irq_init();
/* Actually we've got more interrupts to handle ... */
for (i = SNI_RM200_INT_START; i <= SNI_RM200_INT_END; i++)
set_irq_chip(i, &rm200_irq_type);
sni_hwint = sni_rm200_hwint;
change_c0_status(ST0_IM, IE_IRQ0);
- setup_irq(SNI_RM200_INT_START + 0, &sni_isa_irq);
+ setup_irq(SNI_RM200_INT_START + 0, &sni_rm200_i8259A_irq);
+ setup_irq(SNI_RM200_INT_START + 1, &sni_isa_irq);
}
void __init sni_rm200_init(void)
{
- set_io_port_base(SNI_PORT_BASE + 0x02000000);
- ioport_resource.end += 0x02000000;
}
