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authorAlistair Delva <adelva@google.com>2021-02-16 21:01:22 +0000
committerAutomerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>2021-02-16 21:01:22 +0000
commitefb2826bb8160e2d8e0fcec85133a7468484f9fd (patch)
tree37a21c69306801ee7cdda5167a30896c8740155b /common/fdt_wrappers.c
parentb00a71fc312c9781fa6f404dccfb55b062b2ccac (diff)
parentfaa476c0caaa598afa5a6109d17102db5fe35ec6 (diff)
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Original change: https://android-review.googlesource.com/c/platform/external/arm-trusted-firmware/+/1589611 MUST ONLY BE SUBMITTED BY AUTOMERGER Change-Id: I3a25534ceed4f8e188510641080d8b8ed49b8f62
Diffstat (limited to 'common/fdt_wrappers.c')
-rw-r--r--common/fdt_wrappers.c405
1 files changed, 349 insertions, 56 deletions
diff --git a/common/fdt_wrappers.c b/common/fdt_wrappers.c
index ca5b4556d..5aad14e38 100644
--- a/common/fdt_wrappers.c
+++ b/common/fdt_wrappers.c
@@ -15,90 +15,72 @@
#include <common/fdt_wrappers.h>
/*
- * Read cells from a given property of the given node. At most 2 cells of the
- * property are read, and pointer is updated. Returns 0 on success, and -1 upon
- * error
+ * Read cells from a given property of the given node. Any number of 32-bit
+ * cells of the property can be read. Returns 0 on success, or a negative
+ * FDT error value otherwise.
*/
-int fdtw_read_cells(const void *dtb, int node, const char *prop,
- unsigned int cells, void *value)
+int fdt_read_uint32_array(const void *dtb, int node, const char *prop_name,
+ unsigned int cells, uint32_t *value)
{
- const uint32_t *value_ptr;
- uint32_t hi = 0, lo;
+ const fdt32_t *prop;
int value_len;
assert(dtb != NULL);
- assert(prop != NULL);
+ assert(prop_name != NULL);
assert(value != NULL);
assert(node >= 0);
- /* We expect either 1 or 2 cell property */
- assert(cells <= 2U);
-
/* Access property and obtain its length (in bytes) */
- value_ptr = fdt_getprop_namelen(dtb, node, prop, (int)strlen(prop),
- &value_len);
- if (value_ptr == NULL) {
- WARN("Couldn't find property %s in dtb\n", prop);
- return -1;
+ prop = fdt_getprop(dtb, node, prop_name, &value_len);
+ if (prop == NULL) {
+ WARN("Couldn't find property %s in dtb\n", prop_name);
+ return -FDT_ERR_NOTFOUND;
}
- /* Verify that property length accords with cell length */
- if (NCELLS((unsigned int)value_len) != cells) {
+ /* Verify that property length can fill the entire array. */
+ if (NCELLS((unsigned int)value_len) < cells) {
WARN("Property length mismatch\n");
- return -1;
+ return -FDT_ERR_BADVALUE;
}
- if (cells == 2U) {
- hi = fdt32_to_cpu(*value_ptr);
- value_ptr++;
+ for (unsigned int i = 0U; i < cells; i++) {
+ value[i] = fdt32_to_cpu(prop[i]);
}
- lo = fdt32_to_cpu(*value_ptr);
-
- if (cells == 2U)
- *((uint64_t *) value) = ((uint64_t) hi << 32) | lo;
- else
- *((uint32_t *) value) = lo;
-
return 0;
}
-/*
- * Read cells from a given property of the given node. Any number of 32-bit
- * cells of the property can be read. The fdt pointer is updated. Returns 0 on
- * success, and -1 on error.
- */
-int fdtw_read_array(const void *dtb, int node, const char *prop,
- unsigned int cells, void *value)
+int fdt_read_uint32(const void *dtb, int node, const char *prop_name,
+ uint32_t *value)
{
- const uint32_t *value_ptr;
- int value_len;
+ return fdt_read_uint32_array(dtb, node, prop_name, 1, value);
+}
- assert(dtb != NULL);
- assert(prop != NULL);
- assert(value != NULL);
- assert(node >= 0);
+uint32_t fdt_read_uint32_default(const void *dtb, int node,
+ const char *prop_name, uint32_t dflt_value)
+{
+ uint32_t ret = dflt_value;
+ int err = fdt_read_uint32(dtb, node, prop_name, &ret);
- /* Access property and obtain its length (in bytes) */
- value_ptr = fdt_getprop_namelen(dtb, node, prop, (int)strlen(prop),
- &value_len);
- if (value_ptr == NULL) {
- WARN("Couldn't find property %s in dtb\n", prop);
- return -1;
+ if (err < 0) {
+ return dflt_value;
}
- /* Verify that property length accords with cell length */
- if (NCELLS((unsigned int)value_len) != cells) {
- WARN("Property length mismatch\n");
- return -1;
- }
+ return ret;
+}
- uint32_t *dst = value;
+int fdt_read_uint64(const void *dtb, int node, const char *prop_name,
+ uint64_t *value)
+{
+ uint32_t array[2] = {0, 0};
+ int ret;
- for (unsigned int i = 0U; i < cells; i++) {
- dst[i] = fdt32_to_cpu(value_ptr[i]);
+ ret = fdt_read_uint32_array(dtb, node, prop_name, 2, array);
+ if (ret < 0) {
+ return ret;
}
+ *value = ((uint64_t)array[0] << 32) | array[1];
return 0;
}
@@ -244,3 +226,314 @@ int fdtw_write_inplace_bytes(void *dtb, int node, const char *prop,
return err;
}
+
+static uint64_t fdt_read_prop_cells(const fdt32_t *prop, int nr_cells)
+{
+ uint64_t reg = fdt32_to_cpu(prop[0]);
+
+ if (nr_cells > 1) {
+ reg = (reg << 32) | fdt32_to_cpu(prop[1]);
+ }
+
+ return reg;
+}
+
+int fdt_get_reg_props_by_index(const void *dtb, int node, int index,
+ uintptr_t *base, size_t *size)
+{
+ const fdt32_t *prop;
+ int parent, len;
+ int ac, sc;
+ int cell;
+
+ parent = fdt_parent_offset(dtb, node);
+ if (parent < 0) {
+ return -FDT_ERR_BADOFFSET;
+ }
+
+ ac = fdt_address_cells(dtb, parent);
+ sc = fdt_size_cells(dtb, parent);
+
+ cell = index * (ac + sc);
+
+ prop = fdt_getprop(dtb, node, "reg", &len);
+ if (prop == NULL) {
+ WARN("Couldn't find \"reg\" property in dtb\n");
+ return -FDT_ERR_NOTFOUND;
+ }
+
+ if (((cell + ac + sc) * (int)sizeof(uint32_t)) > len) {
+ return -FDT_ERR_BADVALUE;
+ }
+
+ if (base != NULL) {
+ *base = (uintptr_t)fdt_read_prop_cells(&prop[cell], ac);
+ }
+
+ if (size != NULL) {
+ *size = (size_t)fdt_read_prop_cells(&prop[cell + ac], sc);
+ }
+
+ return 0;
+}
+
+/*******************************************************************************
+ * This function fills reg node info (base & size) with an index found by
+ * checking the reg-names node.
+ * Returns 0 on success and a negative FDT error code on failure.
+ ******************************************************************************/
+int fdt_get_reg_props_by_name(const void *dtb, int node, const char *name,
+ uintptr_t *base, size_t *size)
+{
+ int index;
+
+ index = fdt_stringlist_search(dtb, node, "reg-names", name);
+ if (index < 0) {
+ return index;
+ }
+
+ return fdt_get_reg_props_by_index(dtb, node, index, base, size);
+}
+
+/*******************************************************************************
+ * This function gets the stdout path node.
+ * It reads the value indicated inside the device tree.
+ * Returns node offset on success and a negative FDT error code on failure.
+ ******************************************************************************/
+int fdt_get_stdout_node_offset(const void *dtb)
+{
+ int node;
+ const char *prop, *path;
+ int len;
+
+ /* The /secure-chosen node takes precedence over the standard one. */
+ node = fdt_path_offset(dtb, "/secure-chosen");
+ if (node < 0) {
+ node = fdt_path_offset(dtb, "/chosen");
+ if (node < 0) {
+ return -FDT_ERR_NOTFOUND;
+ }
+ }
+
+ prop = fdt_getprop(dtb, node, "stdout-path", NULL);
+ if (prop == NULL) {
+ return -FDT_ERR_NOTFOUND;
+ }
+
+ /* Determine the actual path length, as a colon terminates the path. */
+ path = strchr(prop, ':');
+ if (path == NULL) {
+ len = strlen(prop);
+ } else {
+ len = path - prop;
+ }
+
+ /* Aliases cannot start with a '/', so it must be the actual path. */
+ if (prop[0] == '/') {
+ return fdt_path_offset_namelen(dtb, prop, len);
+ }
+
+ /* Lookup the alias, as this contains the actual path. */
+ path = fdt_get_alias_namelen(dtb, prop, len);
+ if (path == NULL) {
+ return -FDT_ERR_NOTFOUND;
+ }
+
+ return fdt_path_offset(dtb, path);
+}
+
+
+/*******************************************************************************
+ * Only devices which are direct children of root node use CPU address domain.
+ * All other devices use addresses that are local to the device node and cannot
+ * directly used by CPU. Device tree provides an address translation mechanism
+ * through "ranges" property which provides mappings from local address space to
+ * parent address space. Since a device could be a child of a child node to the
+ * root node, there can be more than one level of address translation needed to
+ * map the device local address space to CPU address space.
+ * fdtw_translate_address() API performs address translation of a local address
+ * to a global address with help of various helper functions.
+ ******************************************************************************/
+
+static bool fdtw_xlat_hit(const uint32_t *value, int child_addr_size,
+ int parent_addr_size, int range_size, uint64_t base_address,
+ uint64_t *translated_addr)
+{
+ uint64_t local_address, parent_address, addr_range;
+
+ local_address = fdt_read_prop_cells(value, child_addr_size);
+ parent_address = fdt_read_prop_cells(value + child_addr_size,
+ parent_addr_size);
+ addr_range = fdt_read_prop_cells(value + child_addr_size +
+ parent_addr_size,
+ range_size);
+ VERBOSE("DT: Address %llx mapped to %llx with range %llx\n",
+ local_address, parent_address, addr_range);
+
+ /* Perform range check */
+ if ((base_address < local_address) ||
+ (base_address >= local_address + addr_range)) {
+ return false;
+ }
+
+ /* Found hit for the addr range that needs to be translated */
+ *translated_addr = parent_address + (base_address - local_address);
+ VERBOSE("DT: child address %llx mapped to %llx in parent bus\n",
+ local_address, parent_address);
+ return true;
+}
+
+#define ILLEGAL_ADDR ULL(~0)
+
+static uint64_t fdtw_search_all_xlat_entries(const void *dtb,
+ const struct fdt_property *ranges_prop,
+ int local_bus, uint64_t base_address)
+{
+ uint64_t translated_addr;
+ const uint32_t *next_entry;
+ int parent_bus_node, nxlat_entries, length;
+ int self_addr_cells, parent_addr_cells, self_size_cells, ncells_xlat;
+
+ /*
+ * The number of cells in one translation entry in ranges is the sum of
+ * the following values:
+ * self#address-cells + parent#address-cells + self#size-cells
+ * Ex: the iofpga ranges property has one translation entry with 4 cells
+ * They represent iofpga#addr-cells + motherboard#addr-cells + iofpga#size-cells
+ * = 1 + 2 + 1
+ */
+
+ parent_bus_node = fdt_parent_offset(dtb, local_bus);
+ self_addr_cells = fdt_address_cells(dtb, local_bus);
+ self_size_cells = fdt_size_cells(dtb, local_bus);
+ parent_addr_cells = fdt_address_cells(dtb, parent_bus_node);
+
+ /* Number of cells per translation entry i.e., mapping */
+ ncells_xlat = self_addr_cells + parent_addr_cells + self_size_cells;
+
+ assert(ncells_xlat > 0);
+
+ /*
+ * Find the number of translations(mappings) specified in the current
+ * `ranges` property. Note that length represents number of bytes and
+ * is stored in big endian mode.
+ */
+ length = fdt32_to_cpu(ranges_prop->len);
+ nxlat_entries = (length/sizeof(uint32_t))/ncells_xlat;
+
+ assert(nxlat_entries > 0);
+
+ next_entry = (const uint32_t *)ranges_prop->data;
+
+ /* Iterate over the entries in the "ranges" */
+ for (int i = 0; i < nxlat_entries; i++) {
+ if (fdtw_xlat_hit(next_entry, self_addr_cells,
+ parent_addr_cells, self_size_cells, base_address,
+ &translated_addr)){
+ return translated_addr;
+ }
+ next_entry = next_entry + ncells_xlat;
+ }
+
+ INFO("DT: No translation found for address %llx in node %s\n",
+ base_address, fdt_get_name(dtb, local_bus, NULL));
+ return ILLEGAL_ADDR;
+}
+
+
+/*******************************************************************************
+ * address mapping needs to be done recursively starting from current node to
+ * root node through all intermediate parent nodes.
+ * Sample device tree is shown here:
+
+smb@0,0 {
+ compatible = "simple-bus";
+
+ #address-cells = <2>;
+ #size-cells = <1>;
+ ranges = <0 0 0 0x08000000 0x04000000>,
+ <1 0 0 0x14000000 0x04000000>,
+ <2 0 0 0x18000000 0x04000000>,
+ <3 0 0 0x1c000000 0x04000000>,
+ <4 0 0 0x0c000000 0x04000000>,
+ <5 0 0 0x10000000 0x04000000>;
+
+ motherboard {
+ arm,v2m-memory-map = "rs1";
+ compatible = "arm,vexpress,v2m-p1", "simple-bus";
+ #address-cells = <2>;
+ #size-cells = <1>;
+ ranges;
+
+ iofpga@3,00000000 {
+ compatible = "arm,amba-bus", "simple-bus";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges = <0 3 0 0x200000>;
+ v2m_serial1: uart@a0000 {
+ compatible = "arm,pl011", "arm,primecell";
+ reg = <0x0a0000 0x1000>;
+ interrupts = <0 6 4>;
+ clocks = <&v2m_clk24mhz>, <&v2m_clk24mhz>;
+ clock-names = "uartclk", "apb_pclk";
+ };
+ };
+};
+
+ * As seen above, there are 3 levels of address translations needed. An empty
+ * `ranges` property denotes identity mapping (as seen in `motherboard` node).
+ * Each ranges property can map a set of child addresses to parent bus. Hence
+ * there can be more than 1 (translation) entry in the ranges property as seen
+ * in the `smb` node which has 6 translation entries.
+ ******************************************************************************/
+
+/* Recursive implementation */
+uint64_t fdtw_translate_address(const void *dtb, int node,
+ uint64_t base_address)
+{
+ int length, local_bus_node;
+ const char *node_name;
+ uint64_t global_address;
+
+ local_bus_node = fdt_parent_offset(dtb, node);
+ node_name = fdt_get_name(dtb, local_bus_node, NULL);
+
+ /*
+ * In the example given above, starting from the leaf node:
+ * uart@a000 represents the current node
+ * iofpga@3,00000000 represents the local bus
+ * motherboard represents the parent bus
+ */
+
+ /* Read the ranges property */
+ const struct fdt_property *property = fdt_get_property(dtb,
+ local_bus_node, "ranges", &length);
+
+ if (property == NULL) {
+ if (local_bus_node == 0) {
+ /*
+ * root node doesn't have range property as addresses
+ * are in CPU address space.
+ */
+ return base_address;
+ }
+ INFO("DT: Couldn't find ranges property in node %s\n",
+ node_name);
+ return ILLEGAL_ADDR;
+ } else if (length == 0) {
+ /* empty ranges indicates identity map to parent bus */
+ return fdtw_translate_address(dtb, local_bus_node, base_address);
+ }
+
+ VERBOSE("DT: Translation lookup in node %s at offset %d\n", node_name,
+ local_bus_node);
+ global_address = fdtw_search_all_xlat_entries(dtb, property,
+ local_bus_node, base_address);
+
+ if (global_address == ILLEGAL_ADDR) {
+ return ILLEGAL_ADDR;
+ }
+
+ /* Translate the local device address recursively */
+ return fdtw_translate_address(dtb, local_bus_node, global_address);
+}