aboutsummaryrefslogtreecommitdiff
path: root/lib/utils/fdt
diff options
context:
space:
mode:
authorAtish Patra <atish.patra@wdc.com>2020-03-23 12:48:57 -0700
committerAnup Patel <anup@brainfault.org>2020-03-24 13:29:07 +0530
commitd1d6560a878200679e6e12e77032d06add8847a5 (patch)
tree7635f0cc2d56ca8d2b116368ce428beacf61cc18 /lib/utils/fdt
parentfb84879e66bc5a26241bcf0472688851f7240acb (diff)
platform: fpga/common: Add a fdt parsing helper functions
Different DT based platforms from the sam family may reuse IP blocks with different configurations. These different configurations can be obtained by parsing the device tree. Add a FDT parser framework that can parse various device configurations from device tree. Currently, the parsing algorithms doesn't cover all the use cases or possible combination of DT configurations. It will be improved over time. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup.patel@wdc.com>
Diffstat (limited to 'lib/utils/fdt')
-rw-r--r--lib/utils/fdt/fdt_helper.c116
1 files changed, 116 insertions, 0 deletions
diff --git a/lib/utils/fdt/fdt_helper.c b/lib/utils/fdt/fdt_helper.c
index 2ea52ca..81617c9 100644
--- a/lib/utils/fdt/fdt_helper.c
+++ b/lib/utils/fdt/fdt_helper.c
@@ -11,6 +11,7 @@
#include <sbi/sbi_console.h>
#include <sbi/sbi_platform.h>
#include <sbi/sbi_scratch.h>
+#include <sbi_utils/fdt/fdt_helper.h>
void fdt_cpu_fixup(void *fdt)
{
@@ -198,3 +199,118 @@ void fdt_fixups(void *fdt)
fdt_reserved_memory_fixup(fdt);
}
+
+static int fdt_get_node_addr_size(void *fdt, int node, unsigned long *addr,
+ unsigned long *size)
+{
+ int parent, len, i;
+ int cell_addr, cell_size;
+ const fdt32_t *prop_addr, *prop_size;
+ uint64_t temp = 0;
+
+ parent = fdt_parent_offset(fdt, node);
+ if (parent < 0)
+ return parent;
+ cell_addr = fdt_address_cells(fdt, parent);
+ if (cell_addr < 1)
+ return SBI_ENODEV;
+
+ cell_size = fdt_size_cells(fdt, parent);
+ if (cell_size < 0)
+ return SBI_ENODEV;
+
+ prop_addr = fdt_getprop(fdt, node, "reg", &len);
+ if (!prop_addr)
+ return SBI_ENODEV;
+ prop_size = prop_addr + cell_addr;
+
+ if (addr) {
+ for (i = 0; i < cell_addr; i++)
+ temp = (temp << 32) | fdt32_to_cpu(*prop_addr++);
+ *addr = temp;
+ }
+ temp = 0;
+
+ if (size) {
+ for (i = 0; i < cell_size; i++)
+ temp = (temp << 32) | fdt32_to_cpu(*prop_size++);
+ *size = temp;
+ }
+
+ return 0;
+}
+
+int fdt_parse_uart8250(void *fdt, struct platform_uart_data *uart,
+ const char *compatible)
+{
+ int nodeoffset, len, rc;
+ fdt32_t *val;
+ unsigned long reg_addr, reg_size;
+
+ /**
+ * TODO: We don't know how to handle multiple nodes with the same
+ * compatible sring. Just return the first node for now.
+ */
+
+ nodeoffset = fdt_node_offset_by_compatible(fdt, -1, compatible);
+ if (nodeoffset < 0)
+ return nodeoffset;
+
+ rc = fdt_get_node_addr_size(fdt, nodeoffset, &reg_addr, &reg_size);
+ if (rc < 0 || !reg_addr || !reg_size)
+ return SBI_ENODEV;
+ uart->addr = reg_addr;
+
+ /**
+ * UART address is mandaotry. clock-frequency and current-speed may not
+ * be present. Don't return error.
+ */
+ val = (fdt32_t *)fdt_getprop(fdt, nodeoffset, "clock-frequency", &len);
+ if (len > 0 && val)
+ uart->freq = fdt32_to_cpu(*val);
+
+ val = (fdt32_t *)fdt_getprop(fdt, nodeoffset, "current-speed", &len);
+ if (len > 0 && val)
+ uart->baud = fdt32_to_cpu(*val);
+
+ return 0;
+}
+
+int fdt_parse_plic(void *fdt, struct platform_plic_data *plic,
+ const char *compatible)
+{
+ int nodeoffset, len, rc;
+ const fdt32_t *val;
+ unsigned long reg_addr, reg_size;
+
+ nodeoffset = fdt_node_offset_by_compatible(fdt, -1, compatible);
+ if (nodeoffset < 0)
+ return nodeoffset;
+
+ rc = fdt_get_node_addr_size(fdt, nodeoffset, &reg_addr, &reg_size);
+ if (rc < 0 || !reg_addr || !reg_size)
+ return SBI_ENODEV;
+ plic->addr = reg_addr;
+
+ val = fdt_getprop(fdt, nodeoffset, "riscv,ndev", &len);
+ if (len > 0)
+ plic->num_src = fdt32_to_cpu(*val);
+
+ return 0;
+}
+
+int fdt_parse_clint(void *fdt, unsigned long *clint_addr,
+ const char *compatible)
+{
+ int nodeoffset, rc;
+
+ nodeoffset = fdt_node_offset_by_compatible(fdt, -1, compatible);
+ if (nodeoffset < 0)
+ return nodeoffset;
+
+ rc = fdt_get_node_addr_size(fdt, nodeoffset, clint_addr, NULL);
+ if (rc < 0 || !clint_addr)
+ return SBI_ENODEV;
+
+ return 0;
+}