sh: INTC ioremap support

Extend the INTC code with ioremap() support V2.

Support INTC controllers that are not accessible through
a 1:1 virt:phys window. Needed by SH-Mobile ARM INTCS.

The INTC code behaves as usual if the io window resource
is omitted. The slow phys->virt lookup only happens during
setup. The fast path code operates on virtual addresses.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

2 files changed, 78 insertions, 10 deletions

diff --git a/drivers/sh/intc.c b/drivers/sh/intc.c
index d4aa4d1e8dce..a700dfec8dc3 100644
--- a/drivers/sh/intc.c
+++ b/drivers/sh/intc.c
@@ -43,6 +43,12 @@ struct intc_handle_int {
         unsigned long handle;
 };
 
+struct intc_window {
+        phys_addr_t phys;
+        void __iomem *virt;
+        unsigned long size;
+};
+
 struct intc_desc_int {
         struct list_head list;
         struct sys_device sysdev;
@@ -56,6 +62,8 @@ struct intc_desc_int {
         unsigned int nr_prio;
         struct intc_handle_int *sense;
         unsigned int nr_sense;
+        struct intc_window *window;
+        unsigned int nr_windows;
         struct irq_chip chip;
 };
 
@@ -420,11 +428,39 @@ static int intc_set_sense(unsigned int irq, unsigned int type)
         return 0;
 }
 
+static unsigned long intc_phys_to_virt(struct intc_desc_int *d,
+                                       unsigned long address)
+{
+        struct intc_window *window;
+        int k;
+
+        /* scan through physical windows and convert address */
+        for (k = 0; k < d->nr_windows; k++) {
+                window = d->window + k;
+
+                if (address < window->phys)
+                        continue;
+
+                if (address >= (window->phys + window->size))
+                        continue;
+
+                address -= window->phys;
+                address += (unsigned long)window->virt;
+
+                return address;
+        }
+
+        /* no windows defined, register must be 1:1 mapped virt:phys */
+        return address;
+}
+
 static unsigned int __init intc_get_reg(struct intc_desc_int *d,
-                                 unsigned long address)
+                                        unsigned long address)
 {
         unsigned int k;
 
+        address = intc_phys_to_virt(d, address);
+
         for (k = 0; k < d->nr_reg; k++) {
                 if (d->reg[k] == address)
                         return k;
@@ -774,6 +810,8 @@ static unsigned int __init save_reg(struct intc_desc_int *d,
                                     unsigned int smp)
 {
         if (value) {
+                value = intc_phys_to_virt(d, value);
+
                 d->reg[cnt] = value;
 #ifdef CONFIG_SMP
                 d->smp[cnt] = smp;
@@ -794,6 +832,7 @@ int __init register_intc_controller(struct intc_desc *desc)
         unsigned int i, k, smp;
         struct intc_hw_desc *hw = &desc->hw;
         struct intc_desc_int *d;
+        struct resource *res;
 
         d = kzalloc(sizeof(*d), GFP_NOWAIT);
         if (!d)
@@ -802,6 +841,25 @@ int __init register_intc_controller(struct intc_desc *desc)
         INIT_LIST_HEAD(&d->list);
         list_add(&d->list, &intc_list);
 
+        if (desc->num_resources) {
+                d->nr_windows = desc->num_resources;
+                d->window = kzalloc(d->nr_windows * sizeof(*d->window),
+                                    GFP_NOWAIT);
+                if (!d->window)
+                        goto err1;
+
+                for (k = 0; k < d->nr_windows; k++) {
+                        res = desc->resource + k;
+                        WARN_ON(resource_type(res) != IORESOURCE_MEM);
+                        d->window[k].phys = res->start;
+                        d->window[k].size = resource_size(res);
+                        d->window[k].virt = ioremap_nocache(res->start,
+                                                         resource_size(res));
+                        if (!d->window[k].virt)
+                                goto err2;
+                }
+        }
+
         d->nr_reg = hw->mask_regs ? hw->nr_mask_regs * 2 : 0;
         d->nr_reg += hw->prio_regs ? hw->nr_prio_regs * 2 : 0;
         d->nr_reg += hw->sense_regs ? hw->nr_sense_regs : 0;
@@ -809,12 +867,12 @@ int __init register_intc_controller(struct intc_desc *desc)
 
         d->reg = kzalloc(d->nr_reg * sizeof(*d->reg), GFP_NOWAIT);
         if (!d->reg)
-                goto err1;
+                goto err2;
 
 #ifdef CONFIG_SMP
         d->smp = kzalloc(d->nr_reg * sizeof(*d->smp), GFP_NOWAIT);
         if (!d->smp)
-                goto err2;
+                goto err3;
 #endif
         k = 0;
 
@@ -830,7 +888,7 @@ int __init register_intc_controller(struct intc_desc *desc)
                 d->prio = kzalloc(hw->nr_vectors * sizeof(*d->prio),
                                   GFP_NOWAIT);
                 if (!d->prio)
-                        goto err3;
+                        goto err4;
 
                 for (i = 0; i < hw->nr_prio_regs; i++) {
                         smp = IS_SMP(hw->prio_regs[i]);
@@ -843,7 +901,7 @@ int __init register_intc_controller(struct intc_desc *desc)
                 d->sense = kzalloc(hw->nr_vectors * sizeof(*d->sense),
                                    GFP_NOWAIT);
                 if (!d->sense)
-                        goto err4;
+                        goto err5;
 
                 for (i = 0; i < hw->nr_sense_regs; i++)
                         k += save_reg(d, k, hw->sense_regs[i].reg, 0);
@@ -925,17 +983,23 @@ int __init register_intc_controller(struct intc_desc *desc)
                 intc_enable_disable_enum(desc, d, desc->force_enable, 1);
 
         return 0;
- err4:
+err5:
         kfree(d->prio);
- err3:
+err4:
 #ifdef CONFIG_SMP
         kfree(d->smp);
- err2:
+err3:
 #endif
         kfree(d->reg);
- err1:
+err2:
+        for (k = 0; k < d->nr_windows; k++)
+                if (d->window[k].virt)
+                        iounmap(d->window[k].virt);
+
+        kfree(d->window);
+err1:
         kfree(d);
- err0:
+err0:
         pr_err("unable to allocate INTC memory\n");
 
         return -ENOMEM;
diff --git a/include/linux/sh_intc.h b/include/linux/sh_intc.h
index df3777035936..01d8168c5a1b 100644
--- a/include/linux/sh_intc.h
+++ b/include/linux/sh_intc.h
@@ -1,6 +1,8 @@
 #ifndef __SH_INTC_H
 #define __SH_INTC_H
 
+#include <linux/ioport.h>
+
 typedef unsigned char intc_enum;
 
 struct intc_vect {
@@ -71,6 +73,8 @@ struct intc_hw_desc {
 
 struct intc_desc {
         char *name;
+        struct resource *resource;
+        unsigned int num_resources;
         intc_enum force_enable;
         intc_enum force_disable;
         struct intc_hw_desc hw;