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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [RFC 10/29] xen/arm: Add helpers to retrieve an interrupt description from the device tree
Signed-off-by: Julien Grall <julien.grall@xxxxxxxxxx>
---
xen/common/device_tree.c | 362 +++++++++++++++++++++++++++++++++++++++++
xen/include/xen/device_tree.h | 99 +++++++++++
xen/include/xen/irq.h | 25 +++
3 files changed, 486 insertions(+)
diff --git a/xen/common/device_tree.c b/xen/common/device_tree.c
index 001188a..c623fe2 100644
--- a/xen/common/device_tree.c
+++ b/xen/common/device_tree.c
@@ -27,8 +27,11 @@
struct dt_early_info __initdata early_info;
void *device_tree_flattened;
+dt_irq_xlate_func dt_irq_xlate;
/* Host device tree */
struct dt_device_node *dt_host;
+/* Interrupt controller node*/
+const struct dt_device_node *dt_interrupt_controller;
/**
* struct dt_alias_prop - Alias property in 'aliases' node
@@ -1017,6 +1020,81 @@ int dt_device_get_address(const struct dt_device_node
*dev, int index,
return 0;
}
+/**
+ * dt_find_node_by_phandle - Find a node given a phandle
+ * @handle: phandle of the node to find
+ *
+ * Returns a node pointer.
+ */
+static const struct dt_device_node *dt_find_node_by_phandle(dt_phandle handle)
+{
+ const struct dt_device_node *np;
+
+ for_each_device_node(dt_host, np)
+ if ( np->phandle == handle )
+ break;
+
+ return np;
+}
+
+/**
+ * dt_irq_find_parent - Given a device node, find its interrupt parent node
+ * @child: pointer to device node
+ *
+ * Returns a pointer to the interrupt parent node, or NULL if the interrupt
+ * parent could not be determined.
+ */
+static const struct dt_device_node *
+dt_irq_find_parent(const struct dt_device_node *child)
+{
+ const struct dt_device_node *p;
+ const __be32 *parp;
+
+ do
+ {
+ parp = dt_get_property(child, "interrupt-parent", NULL);
+ if ( parp == NULL )
+ p = dt_get_parent(child);
+ else
+ p = dt_find_node_by_phandle(be32_to_cpup(parp));
+ child = p;
+ } while ( p && dt_get_property(p, "#interrupt-cells", NULL) == NULL );
+
+ return p;
+}
+
+unsigned int dt_number_of_irq(const struct dt_device_node *device)
+{
+ const struct dt_device_node *p;
+ const __be32 *intspec, *tmp;
+ u32 intsize, intlen;
+
+ dt_dprintk("dt_irq_number: dev=%s\n", device->full_name);
+
+ /* Get the interrupts property */
+ intspec = dt_get_property(device, "interrupts", &intlen);
+ if ( intspec == NULL )
+ return 0;
+ intlen /= sizeof(*intspec);
+
+ dt_dprintk(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);
+
+ /* Look for the interrupt parent. */
+ p = dt_irq_find_parent(device);
+ if ( p == NULL )
+ return 0;
+
+ /* Get size of interrupt specifier */
+ tmp = dt_get_property(p, "#interrupt-cells", NULL);
+ if ( tmp == NULL )
+ return 0;
+ intsize = be32_to_cpu(*tmp);
+
+ dt_dprintk(" intsize=%d intlen=%d\n", intsize, intlen);
+
+ return (intlen / intsize);
+}
+
unsigned int dt_number_of_address(const struct dt_device_node *dev)
{
const __be32 *prop;
@@ -1048,6 +1126,274 @@ unsigned int dt_number_of_address(const struct
dt_device_node *dev)
}
/**
+ * dt_irq_map_raw - Low level interrupt tree parsing
+ * @parent: the device interrupt parent
+ * @intspec: interrupt specifier ("interrupts" property of the device)
+ * @ointsize: size of the passed in interrupt specifier
+ * @addr: address specifier (start of "reg" property of the device)
+ * @oirq: structure dt_raw_irq filled by this function
+ *
+ * Returns 0 on success and a negative number on error
+ *
+ * This function is a low-level interrupt tree walking function. It
+ * can be used to do a partial walk with synthetized reg and interrupts
+ * properties, for example when resolving PCI interrupts when no device
+ * node exist for the parent.
+ */
+static int dt_irq_map_raw(const struct dt_device_node *parent,
+ const __be32 *intspec, u32 ointsize,
+ const __be32 *addr,
+ struct dt_raw_irq *oirq)
+{
+ const struct dt_device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
+ const __be32 *tmp, *imap, *imask;
+ u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
+ u32 imaplen;
+ int match, i;
+
+ dt_dprintk("dt_irq_map_raw: par=%s,intspec=[0x%08x
0x%08x...],ointsize=%d\n",
+ parent->full_name, be32_to_cpup(intspec),
+ be32_to_cpup(intspec + 1), ointsize);
+
+ ipar = parent;
+
+ /* First get the #interrupt-cells property of the current cursor
+ * that tells us how to interpret the passed-in intspec. If there
+ * is none, we are nice and just walk up the tree
+ */
+ do {
+ tmp = dt_get_property(ipar, "#interrupt-cells", NULL);
+ if ( tmp != NULL )
+ {
+ intsize = be32_to_cpu(*tmp);
+ break;
+ }
+ tnode = ipar;
+ ipar = dt_irq_find_parent(ipar);
+ } while ( ipar );
+ if ( ipar == NULL )
+ {
+ dt_dprintk(" -> no parent found !\n");
+ goto fail;
+ }
+
+ dt_dprintk("dt_irq_map_raw: ipar=%s, size=%d\n", ipar->full_name, intsize);
+
+ if ( ointsize != intsize )
+ return -EINVAL;
+
+ /* Look for this #address-cells. We have to implement the old linux
+ * trick of looking for the parent here as some device-trees rely on it
+ */
+ old = ipar;
+ do {
+ tmp = dt_get_property(old, "#address-cells", NULL);
+ tnode = dt_get_parent(old);
+ old = tnode;
+ } while ( old && tmp == NULL );
+
+ old = NULL;
+ addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);
+
+ dt_dprintk(" -> addrsize=%d\n", addrsize);
+
+ /* Now start the actual "proper" walk of the interrupt tree */
+ while ( ipar != NULL )
+ {
+ /* Now check if cursor is an interrupt-controller and if it is
+ * then we are done
+ */
+ if ( dt_get_property(ipar, "interrupt-controller", NULL) != NULL )
+ {
+ dt_dprintk(" -> got it !\n");
+ if ( intsize > DT_MAX_IRQ_SPEC )
+ {
+ dt_dprintk(" -> intsize(%u) greater than
DT_MAX_IRQ_SPEC(%u)\n",
+ intsize, DT_MAX_IRQ_SPEC);
+ goto fail;
+ }
+ for ( i = 0; i < intsize; i++ )
+ oirq->specifier[i] = dt_read_number(intspec + i, 1);
+ oirq->size = intsize;
+ oirq->controller = ipar;
+ return 0;
+ }
+
+ /* Now look for an interrupt-map */
+ imap = dt_get_property(ipar, "interrupt-map", &imaplen);
+ /* No interrupt map, check for an interrupt parent */
+ if ( imap == NULL )
+ {
+ dt_dprintk(" -> no map, getting parent\n");
+ newpar = dt_irq_find_parent(ipar);
+ goto skiplevel;
+ }
+ imaplen /= sizeof(u32);
+
+ /* Look for a mask */
+ imask = dt_get_property(ipar, "interrupt-map-mask", NULL);
+
+ /* If we were passed no "reg" property and we attempt to parse
+ * an interrupt-map, then #address-cells must be 0.
+ * Fail if it's not.
+ */
+ if ( addr == NULL && addrsize != 0 )
+ {
+ dt_dprintk(" -> no reg passed in when needed !\n");
+ goto fail;
+ }
+
+ /* Parse interrupt-map */
+ match = 0;
+ while ( imaplen > (addrsize + intsize + 1) && !match )
+ {
+ /* Compare specifiers */
+ match = 1;
+ for ( i = 0; i < addrsize && match; ++i )
+ {
+ __be32 mask = imask ? imask[i] : cpu_to_be32(0xffffffffu);
+ match = ((addr[i] ^ imap[i]) & mask) == 0;
+ }
+ for ( ; i < (addrsize + intsize) && match; ++i )
+ {
+ __be32 mask = imask ? imask[i] : cpu_to_be32(0xffffffffu);
+ match = ((intspec[i-addrsize] ^ imap[i]) & mask) == 0;
+ }
+ imap += addrsize + intsize;
+ imaplen -= addrsize + intsize;
+
+ dt_dprintk(" -> match=%d (imaplen=%d)\n", match, imaplen);
+
+ /* Get the interrupt parent */
+ newpar = dt_find_node_by_phandle(be32_to_cpup(imap));
+ imap++;
+ --imaplen;
+
+ /* Check if not found */
+ if ( newpar == NULL )
+ {
+ dt_dprintk(" -> imap parent not found !\n");
+ goto fail;
+ }
+
+ /* Get #interrupt-cells and #address-cells of new
+ * parent
+ */
+ tmp = dt_get_property(newpar, "#interrupt-cells", NULL);
+ if ( tmp == NULL )
+ {
+ dt_dprintk(" -> parent lacks #interrupt-cells!\n");
+ goto fail;
+ }
+ newintsize = be32_to_cpu(*tmp);
+ tmp = dt_get_property(newpar, "#address-cells", NULL);
+ newaddrsize = (tmp == NULL) ? 0 : be32_to_cpu(*tmp);
+
+ dt_dprintk(" -> newintsize=%d, newaddrsize=%d\n",
+ newintsize, newaddrsize);
+
+ /* Check for malformed properties */
+ if ( imaplen < (newaddrsize + newintsize) )
+ goto fail;
+
+ imap += newaddrsize + newintsize;
+ imaplen -= newaddrsize + newintsize;
+
+ dt_dprintk(" -> imaplen=%d\n", imaplen);
+ }
+ if ( !match )
+ goto fail;
+
+ old = newpar;
+ addrsize = newaddrsize;
+ intsize = newintsize;
+ intspec = imap - intsize;
+ addr = intspec - addrsize;
+
+ skiplevel:
+ /* Iterate again with new parent */
+ dt_dprintk(" -> new parent: %s\n", dt_node_full_name(newpar));
+ ipar = newpar;
+ newpar = NULL;
+ }
+fail:
+ return -EINVAL;
+}
+
+int dt_device_get_raw_irq(const struct dt_device_node *device, int index,
+ struct dt_raw_irq *out_irq)
+{
+ const struct dt_device_node *p;
+ const __be32 *intspec, *tmp, *addr;
+ u32 intsize, intlen;
+ int res = -EINVAL;
+
+ dt_dprintk("dt_device_get_raw_irq: dev=%s, index=%d\n",
+ device->full_name, index);
+
+ /* Get the interrupts property */
+ intspec = dt_get_property(device, "interrupts", &intlen);
+ if ( intspec == NULL )
+ return -EINVAL;
+ intlen /= sizeof(*intspec);
+
+ dt_dprintk(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);
+
+ /* Get the reg property (if any) */
+ addr = dt_get_property(device, "reg", NULL);
+
+ /* Look for the interrupt parent. */
+ p = dt_irq_find_parent(device);
+ if ( p == NULL )
+ return -EINVAL;
+
+ /* Get size of interrupt specifier */
+ tmp = dt_get_property(p, "#interrupt-cells", NULL);
+ if ( tmp == NULL )
+ goto out;
+ intsize = be32_to_cpu(*tmp);
+
+ dt_dprintk(" intsize=%d intlen=%d\n", intsize, intlen);
+
+ /* Check index */
+ if ( (index + 1) * intsize > intlen )
+ goto out;
+
+ /* Get new specifier and map it */
+ res = dt_irq_map_raw(p, intspec + index * intsize, intsize,
+ addr, out_irq);
+ if ( res )
+ goto out;
+out:
+ return res;
+}
+
+int dt_irq_translate(const struct dt_raw_irq *raw,
+ struct dt_irq *out_irq)
+{
+ ASSERT(dt_irq_xlate != NULL);
+
+ /* TODO: Retrieve the right irq_xlate. This is only work for the gic */
+
+ return dt_irq_xlate(raw->specifier, raw->size,
+ &out_irq->irq, &out_irq->type);
+}
+
+int dt_device_get_irq(const struct dt_device_node *device, int index,
+ struct dt_irq *out_irq)
+{
+ struct dt_raw_irq raw;
+ int res;
+
+ res = dt_device_get_raw_irq(device, index, &raw);
+
+ if ( res )
+ return res;
+
+ return dt_irq_translate(&raw, out_irq);
+}
+
+/**
* unflatten_dt_node - Alloc and populate a device_node from the flat tree
* @fdt: The parent device tree blob
* @mem: Memory chunk to use for allocating device nodes and properties
@@ -1389,6 +1735,22 @@ static void __init dt_alias_scan(void)
}
}
+struct dt_device_node * __init dt_find_interrupt_controller(const char *compat)
+{
+ struct dt_device_node *np = NULL;
+
+ while ( (np = dt_find_compatible_node(np, NULL, compat)) )
+ {
+ if ( !dt_find_property(np, "interrupt-controller", NULL) )
+ continue;
+
+ if ( dt_get_parent(np) )
+ break;
+ }
+
+ return np;
+}
+
void __init dt_unflatten_host_device_tree(void)
{
__unflatten_device_tree(device_tree_flattened, &dt_host);
diff --git a/xen/include/xen/device_tree.h b/xen/include/xen/device_tree.h
index 020a3d0..c897eab 100644
--- a/xen/include/xen/device_tree.h
+++ b/xen/include/xen/device_tree.h
@@ -101,6 +101,36 @@ struct dt_device_node {
};
+/**
+ * dt_irq - describe an IRQ in the device tree
+ * @irq: IRQ number
+ * @type: IRQ type (see IRQ_TYPE_* in include/xen/irq.h)
+ *
+ * This structure is returned when an interrupt is mapped.
+ */
+struct dt_irq {
+ unsigned int irq;
+ unsigned int type;
+};
+
+/**
+ * dt_raw_irq - container for device_node/irq_specifier for an irq controller
+ * @controller: pointer to interrupt controller deivce tree node
+ * @size: size of interrupt specifier
+ * @specifier: array of cells @size long specifing the specific interrupt
+ *
+ * This structure is returned when an interrupt is mapped but not translated.
+ */
+#define DT_MAX_IRQ_SPEC 4 /* We handle specifiers of at most 4 cells */
+struct dt_raw_irq {
+ const struct dt_device_node *controller;
+ u32 size;
+ u32 specifier[DT_MAX_IRQ_SPEC];
+};
+
+#define dt_irq(irq) ((irq)->irq)
+#define dt_irq_flags(irq) ((irq)->flags)
+
typedef int (*device_tree_node_func)(const void *fdt,
int node, const char *name, int depth,
u32 address_cells, u32 size_cells,
@@ -142,11 +172,40 @@ void __init dt_unflatten_host_device_tree(void);
void __init dt_switch_to_printk(void);
/**
+ * IRQ translation callback
+ * TODO: For the moment we assume that we only have ONE
+ * interrupt-controller.
+ */
+typedef int (*dt_irq_xlate_func)(const u32 *intspec, unsigned int intsize,
+ unsigned int *out_hwirq,
+ unsigned int *out_type);
+extern dt_irq_xlate_func dt_irq_xlate;
+
+/**
* Host device tree
* DO NOT modify it!
*/
extern struct dt_device_node *dt_host;
+/**
+ * Primary interrupt controller
+ * Exynos SOC has an interrupt combiner, interrupt has no physical
+ * meaning when it's not connected to the primary controller.
+ * We will only map interrupt whose parent controller is
+ * dt_interrupt_controller. It should always be a GIC.
+ * TODO: Handle multiple GIC
+ */
+extern const struct dt_device_node *dt_interrupt_controller;
+
+/**
+ * Find the interrupt controller
+ * For the moment we handle only one interrupt controller: the first
+ * one without parent and is compatible with the string "compat".
+ *
+ * If found, return the interrupt controller device node.
+ */
+struct dt_device_node * __init dt_find_interrupt_controller(const char
*compat);
+
#define dt_node_cmp(s1, s2) strcmp((s1), (s2))
#define dt_compat_cmp(s1, s2, l) strnicmp((s1), (s2), l)
@@ -291,6 +350,15 @@ int dt_device_get_address(const struct dt_device_node
*dev, int index,
u64 *addr, u64 *size);
/**
+ * dt_number_of_irq - Get the number of IRQ for a device
+ * @device: the device whose number of interrupt is to be retrieved
+ *
+ * Return the number of irq for this device or 0 if there is no
+ * interrupt or an error occurred.
+ */
+unsigned int dt_number_of_irq(const struct dt_device_node *device);
+
+/**
* dt_number_of_address - Get the number of addresse for a device
* @device: the device whose number of address is to be retrieved
*
@@ -300,6 +368,37 @@ int dt_device_get_address(const struct dt_device_node
*dev, int index,
unsigned int dt_number_of_address(const struct dt_device_node *device);
/**
+ * dt_device_get_irq - Resolve an interrupt for a device
+ * @device: the device whose interrupt is to be resolved
+ * @index: index of the interrupt to resolve
+ * @out_irq: structure dt_irq filled by this function
+ *
+ * This function resolves an interrupt, walking the tree, for a given
+ * device-tree node. It's the high level pendant to dt_device_get_raw_irq().
+ */
+int dt_device_get_irq(const struct dt_device_node *device, int index,
+ struct dt_irq *irq);
+
+/**
+ * dt_device_get_raw_irq - Resolve an interrupt for a device without
translation
+ * @device: the device whose interrupt is to be resolved
+ * @index: index of the interrupt to resolve
+ * @out_irq: structure dt_raw_irq filled by this function
+ *
+ * This function resolves an interrupt for a device, no translation is
+ * made. dt_irq_translate can be called after.
+ */
+int dt_device_get_raw_irq(const struct dt_device_node *device, int index,
+ struct dt_raw_irq *irq);
+
+/**
+ * dt_irq_transalte - Translate an irq
+ * @raw: IRQ to translate (raw format)
+ * @out_irq: structure dt_irq filled by this function
+ */
+int dt_irq_translate(const struct dt_raw_irq *raw, struct dt_irq *out_irq);
+
+/**
* dt_n_size_cells - Helper to retrieve the number of cell for the size
* @np: node to get the value
*
diff --git a/xen/include/xen/irq.h b/xen/include/xen/irq.h
index 7386358..42dc172 100644
--- a/xen/include/xen/irq.h
+++ b/xen/include/xen/irq.h
@@ -33,6 +33,31 @@ struct irqaction {
#define NEVER_ASSIGN_IRQ (-2)
#define FREE_TO_ASSIGN_IRQ (-3)
+/**
+ * IRQ line type.
+ *
+ * IRQ_TYPE_NONE - default, unspecified type
+ * IRQ_TYPE_EDGE_RISING - rising edge triggered
+ * IRQ_TYPE_EDGE_FALLING - falling edge triggered
+ * IRQ_TYPE_EDGE_BOTH - rising and falling edge triggered
+ * IRQ_TYPE_LEVEL_HIGH - high level triggered
+ * IRQ_TYPE_LEVEL_LOW - low level triggered
+ * IRQ_TYPE_LEVEL_MASK - Mask to filter out the level bits
+ * IRQ_TYPE_SENSE_MASK - Mask for all the above bits
+ */
+#define IRQ_TYPE_NONE 0x00000000
+#define IRQ_TYPE_EDGE_RISING 0x00000001
+#define IRQ_TYPE_EDGE_FALLING 0x00000002
+#define IRQ_TYPE_EDGE_BOTH (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)
+#define IRQ_TYPE_LEVEL_HIGH 0x00000004
+#define IRQ_TYPE_LEVEL_LOW 0x00000008
+#define IRQ_TYPE_LEVEL_MASK (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)
+#define IRQ_TYPE_SENSE_MASK 0x0000000f
+
+/* If type == IRQ_TYPE_NONE, assume we use level triggered */
+#define irq_is_level_trigger(irq) \
+ (((irq)->type & IRQ_TYPE_LEVEL_MASK) || ((irq)->type == IRQ_TYPE_NONE))
+
struct irq_desc;
/*
--
Julien Grall
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