[POWERPC] Improve MPIC driver auto-configuration from DT

This patch applies on top of the MPIC DCR support. It makes the MPIC
driver capable of a lot more auto-configuration based on the device-tree,
for example, it can retreive it's own physical address if not passed as
an argument, find out if it's DCR or MMIO mapped, and set the BIG_ENDIAN
flag automatically in the presence of a "big-endian" property in the
device-tree node.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 37 insertions, 13 deletions

diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index 909306ca04f4..411480d5c626 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -894,7 +894,7 @@ static struct irq_host_ops mpic_host_ops = {
  */
 
 struct mpic * __init mpic_alloc(struct device_node *node,
-                                unsigned long phys_addr,
+                                phys_addr_t phys_addr,
                                 unsigned int flags,
                                 unsigned int isu_size,
                                 unsigned int irq_count,
@@ -904,6 +904,7 @@ struct mpic * __init mpic_alloc(struct device_node *node,
         u32             reg;
         const char      *vers;
         int             i;
+        u64             paddr = phys_addr;
 
         mpic = alloc_bootmem(sizeof(struct mpic));
         if (mpic == NULL)
@@ -943,6 +944,11 @@ struct mpic * __init mpic_alloc(struct device_node *node,
         mpic->irq_count = irq_count;
         mpic->num_sources = 0; /* so far */
 
+        /* Check for "big-endian" in device-tree */
+        if (node && get_property(node, "big-endian", NULL) != NULL)
+                mpic->flags |= MPIC_BIG_ENDIAN;
+
+
 #ifdef CONFIG_MPIC_WEIRD
         mpic->hw_set = mpic_infos[MPIC_GET_REGSET(flags)];
 #endif
@@ -951,11 +957,17 @@ struct mpic * __init mpic_alloc(struct device_node *node,
         mpic->reg_type = (flags & MPIC_BIG_ENDIAN) ?
                 mpic_access_mmio_be : mpic_access_mmio_le;
 
+        /* If no physical address is passed in, a device-node is mandatory */
+        BUG_ON(paddr == 0 && node == NULL);
+
+        /* If no physical address passed in, check if it's dcr based */
+        if (paddr == 0 && get_property(node, "dcr-reg", NULL) != NULL)
+                mpic->flags |= MPIC_USES_DCR;
+
 #ifdef CONFIG_PPC_DCR
         if (mpic->flags & MPIC_USES_DCR) {
                 const u32 *dbasep;
-                BUG_ON(mpic->of_node == NULL);
-                dbasep = get_property(mpic->of_node, "dcr-reg", NULL);
+                dbasep = get_property(node, "dcr-reg", NULL);
                 BUG_ON(dbasep == NULL);
                 mpic->dcr_base = *dbasep;
                 mpic->reg_type = mpic_access_dcr;
@@ -964,9 +976,20 @@ struct mpic * __init mpic_alloc(struct device_node *node,
         BUG_ON (mpic->flags & MPIC_USES_DCR);
 #endif /* CONFIG_PPC_DCR */
 
+        /* If the MPIC is not DCR based, and no physical address was passed
+         * in, try to obtain one
+         */
+        if (paddr == 0 && !(mpic->flags & MPIC_USES_DCR)) {
+                const u32 *reg;
+                reg = get_property(node, "reg", NULL);
+                BUG_ON(reg == NULL);
+                paddr = of_translate_address(node, reg);
+                BUG_ON(paddr == OF_BAD_ADDR);
+        }
+
         /* Map the global registers */
-        mpic_map(mpic, phys_addr, &mpic->gregs, MPIC_INFO(GREG_BASE), 0x1000);
-        mpic_map(mpic, phys_addr, &mpic->tmregs, MPIC_INFO(TIMER_BASE), 0x1000);
+        mpic_map(mpic, paddr, &mpic->gregs, MPIC_INFO(GREG_BASE), 0x1000);
+        mpic_map(mpic, paddr, &mpic->tmregs, MPIC_INFO(TIMER_BASE), 0x1000);
 
         /* Reset */
         if (flags & MPIC_WANTS_RESET) {
@@ -991,7 +1014,7 @@ struct mpic * __init mpic_alloc(struct device_node *node,
 
         /* Map the per-CPU registers */
         for (i = 0; i < mpic->num_cpus; i++) {
-                mpic_map(mpic, phys_addr, &mpic->cpuregs[i],
+                mpic_map(mpic, paddr, &mpic->cpuregs[i],
                          MPIC_INFO(CPU_BASE) + i * MPIC_INFO(CPU_STRIDE),
                          0x1000);
         }
@@ -999,7 +1022,7 @@ struct mpic * __init mpic_alloc(struct device_node *node,
         /* Initialize main ISU if none provided */
         if (mpic->isu_size == 0) {
                 mpic->isu_size = mpic->num_sources;
-                mpic_map(mpic, phys_addr, &mpic->isus[0],
+                mpic_map(mpic, paddr, &mpic->isus[0],
                          MPIC_INFO(IRQ_BASE), MPIC_INFO(IRQ_STRIDE) * mpic->isu_size);
         }
         mpic->isu_shift = 1 + __ilog2(mpic->isu_size - 1);
@@ -1020,10 +1043,11 @@ struct mpic * __init mpic_alloc(struct device_node *node,
                 vers = "<unknown>";
                 break;
         }
-        printk(KERN_INFO "mpic: Setting up MPIC \"%s\" version %s at %lx, max %d CPUs\n",
-               name, vers, phys_addr, mpic->num_cpus);
-        printk(KERN_INFO "mpic: ISU size: %d, shift: %d, mask: %x\n", mpic->isu_size,
-               mpic->isu_shift, mpic->isu_mask);
+        printk(KERN_INFO "mpic: Setting up MPIC \"%s\" version %s at %llx,"
+               " max %d CPUs\n",
+               name, vers, (unsigned long long)paddr, mpic->num_cpus);
+        printk(KERN_INFO "mpic: ISU size: %d, shift: %d, mask: %x\n",
+               mpic->isu_size, mpic->isu_shift, mpic->isu_mask);
 
         mpic->next = mpics;
         mpics = mpic;
@@ -1037,13 +1061,13 @@ struct mpic * __init mpic_alloc(struct device_node *node,
 }
 
 void __init mpic_assign_isu(struct mpic *mpic, unsigned int isu_num,
-                            unsigned long phys_addr)
+                            phys_addr_t paddr)
 {
         unsigned int isu_first = isu_num * mpic->isu_size;
 
         BUG_ON(isu_num >= MPIC_MAX_ISU);
 
-        mpic_map(mpic, phys_addr, &mpic->isus[isu_num], 0,
+        mpic_map(mpic, paddr, &mpic->isus[isu_num], 0,
                  MPIC_INFO(IRQ_STRIDE) * mpic->isu_size);
         if ((isu_first + mpic->isu_size) > mpic->num_sources)
                 mpic->num_sources = isu_first + mpic->isu_size;