Re: [PATCH] bus: fsl-mc: Use common ranges functions

From: Laurentiu Tudor
Date: Wed Jun 21 2023 - 12:19:16 EST




On 6/9/2023 9:32 PM, Rob Herring wrote:
Since commit 3d5089c4263d ("of/address: Add support for 3 address cell
bus"), the DT address functions can handle translating buses with 3
address cells. Replace the custom code with the for_each_of_range()
iterator.

The original code had fallbacks to get "#address-cells"/"#size-cells"
from the bus parent node if they are missing. This is non-standard
behavior, and AFAICT the upstream .dts files never relied on that.

Signed-off-by: Rob Herring <robh@xxxxxxxxxx>

Thanks, Rob!

Reviewed-by: Laurentiu Tudor <laurentiu.tudor@xxxxxxx>
Tested-by: Laurentiu Tudor <laurentiu.tudor@xxxxxxx>

---
Best Regards, Laurentiu

---
drivers/bus/fsl-mc/fsl-mc-bus.c | 90 +++++----------------------------
1 file changed, 13 insertions(+), 77 deletions(-)

diff --git a/drivers/bus/fsl-mc/fsl-mc-bus.c b/drivers/bus/fsl-mc/fsl-mc-bus.c
index 653e2d4c116f..5062d73b13e2 100644
--- a/drivers/bus/fsl-mc/fsl-mc-bus.c
+++ b/drivers/bus/fsl-mc/fsl-mc-bus.c
@@ -999,75 +999,18 @@ struct fsl_mc_device *fsl_mc_get_endpoint(struct fsl_mc_device *mc_dev,
}
EXPORT_SYMBOL_GPL(fsl_mc_get_endpoint);
-static int parse_mc_ranges(struct device *dev,
- int *paddr_cells,
- int *mc_addr_cells,
- int *mc_size_cells,
- const __be32 **ranges_start)
-{
- const __be32 *prop;
- int range_tuple_cell_count;
- int ranges_len;
- int tuple_len;
- struct device_node *mc_node = dev->of_node;
-
- *ranges_start = of_get_property(mc_node, "ranges", &ranges_len);
- if (!(*ranges_start) || !ranges_len) {
- dev_warn(dev,
- "missing or empty ranges property for device tree node '%pOFn'\n",
- mc_node);
- return 0;
- }
-
- *paddr_cells = of_n_addr_cells(mc_node);
-
- prop = of_get_property(mc_node, "#address-cells", NULL);
- if (prop)
- *mc_addr_cells = be32_to_cpup(prop);
- else
- *mc_addr_cells = *paddr_cells;
-
- prop = of_get_property(mc_node, "#size-cells", NULL);
- if (prop)
- *mc_size_cells = be32_to_cpup(prop);
- else
- *mc_size_cells = of_n_size_cells(mc_node);
-
- range_tuple_cell_count = *paddr_cells + *mc_addr_cells +
- *mc_size_cells;
-
- tuple_len = range_tuple_cell_count * sizeof(__be32);
- if (ranges_len % tuple_len != 0) {
- dev_err(dev, "malformed ranges property '%pOFn'\n", mc_node);
- return -EINVAL;
- }
-
- return ranges_len / tuple_len;
-}
-
static int get_mc_addr_translation_ranges(struct device *dev,
struct fsl_mc_addr_translation_range
**ranges,
u8 *num_ranges)
{
- int ret;
- int paddr_cells;
- int mc_addr_cells;
- int mc_size_cells;
- int i;
- const __be32 *ranges_start;
- const __be32 *cell;
-
- ret = parse_mc_ranges(dev,
- &paddr_cells,
- &mc_addr_cells,
- &mc_size_cells,
- &ranges_start);
- if (ret < 0)
- return ret;
+ struct fsl_mc_addr_translation_range *r;
+ struct of_range_parser parser;
+ struct of_range range;
- *num_ranges = ret;
- if (!ret) {
+ of_range_parser_init(&parser, dev->of_node);
+ *num_ranges = of_range_count(&parser);
+ if (!*num_ranges) {
/*
* Missing or empty ranges property ("ranges;") for the
* 'fsl,qoriq-mc' node. In this case, identity mapping
@@ -1083,20 +1026,13 @@ static int get_mc_addr_translation_ranges(struct device *dev,
if (!(*ranges))
return -ENOMEM;
- cell = ranges_start;
- for (i = 0; i < *num_ranges; ++i) {
- struct fsl_mc_addr_translation_range *range = &(*ranges)[i];
-
- range->mc_region_type = of_read_number(cell, 1);
- range->start_mc_offset = of_read_number(cell + 1,
- mc_addr_cells - 1);
- cell += mc_addr_cells;
- range->start_phys_addr = of_read_number(cell, paddr_cells);
- cell += paddr_cells;
- range->end_mc_offset = range->start_mc_offset +
- of_read_number(cell, mc_size_cells);
-
- cell += mc_size_cells;
+ r = *ranges;
+ for_each_of_range(&parser, &range) {
+ r->mc_region_type = range.flags;
+ r->start_mc_offset = range.bus_addr;
+ r->end_mc_offset = range.bus_addr + range.size;
+ r->start_phys_addr = range.cpu_addr;
+ r++;
}
return 0;