[PATCH 0/3] simplefb-fixup: fixes for 64bit systems

[PATCH 0/3] simplefb-fixup: fixes for 64bit systems

[Michael Grzeschik]

This series is containing fixes to hand over the simplefb to 64bit
systems.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
---
Michael Grzeschik (3):
      include: linux: ioport.h: port resource_set_range from linux
      simplefb-fixup: depend res fields on root size-cells and addr-cells
      simplefb-fixup: add reserved memory-region entry for the simple-framebuffer

 drivers/video/simplefb-fixup.c | 29 ++++++++++++++++++++---------
 include/linux/ioport.h         | 31 +++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+), 9 deletions(-)
---
base-commit: 6c85c9d60dd32b42a866aed522ff7e19211ef7d2
change-id: 20251117-simplefb-fixup-3bfdad19358c

Best regards,
-- 
Michael Grzeschik <m.grzeschik@pengutronix.de>

[PATCH 1/3] include: linux: ioport.h: port resource_set_range from linux

[Michael Grzeschik]

This is a preparation patch for potential users to follow.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
---
 include/linux/ioport.h | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 290f9feddcb900d92b61169acc46d7e1ead62c91..e24984f7f722eae5466a4e198457adda6601bf77 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -234,5 +234,36 @@ static inline bool is_reserved_resource(const struct resource *res)
 	return false;
 }
 
+/**
+ * resource_set_size - Calculate resource end address from size and start
+ * @res: Resource descriptor
+ * @size: Size of the resource
+ *
+ * Calculate the end address for @res based on @size.
+ *
+ * Note: The start address of @res must be set when calling this function.
+ * Prefer resource_set_range() if setting both the start address and @size.
+ */
+static inline void resource_set_size(struct resource *res, resource_size_t size)
+{
+	res->end = res->start + size - 1;
+}
+
+/**
+ * resource_set_range - Set resource start and end addresses
+ * @res: Resource descriptor
+ * @start: Start address for the resource
+ * @size: Size of the resource
+ *
+ * Set @res start address and calculate the end address based on @size.
+ */
+static inline void resource_set_range(struct resource *res,
+				      resource_size_t start,
+				      resource_size_t size)
+{
+	res->start = start;
+	resource_set_size(res, size);
+}
+
 #endif /* __ASSEMBLY__ */
 #endif	/* _LINUX_IOPORT_H */

-- 
2.47.3

[PATCH 2/3] simplefb-fixup: depend res fields on root size-cells and addr-cells

[Michael Grzeschik]

With 64bit systems the #size-cells and #addr-cells are different
to 32bit. To align with the spec we define the number of fields
by the roots size and addr cells count.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
---
 drivers/video/simplefb-fixup.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/video/simplefb-fixup.c b/drivers/video/simplefb-fixup.c
index 65e0281a189f23c3b730c7bab56d283cc29700aa..9b39e1ef46d84eed61242119251d340b44d59a6e 100644
--- a/drivers/video/simplefb-fixup.c
+++ b/drivers/video/simplefb-fixup.c
@@ -91,8 +91,14 @@ static int simplefb_create_node(struct device_node *root,
 {
 	struct device_node *node;
 	phys_addr_t screen_base;
-	u32 cells[2];
-	int ret;
+	__be32 cells[4];
+	int addr_cells = 2, size_cells = 1, ret;
+
+	of_property_read_u32(root, "#address-cells", &addr_cells);
+	of_property_read_u32(root, "#size-cells", &size_cells);
+
+	if ((addr_cells + size_cells) > 4)
+		return -EINVAL;
 
 	node = of_create_node(root, "/framebuffer");
 	if (!node)
@@ -107,12 +113,11 @@ static int simplefb_create_node(struct device_node *root,
 		return ret;
 
 	screen_base = virt_to_phys(fbi->screen_base);
-	if (upper_32_bits(screen_base))
-		return -ENOSYS;
 
-	cells[0] = cpu_to_be32(lower_32_bits(screen_base));
-	cells[1] = cpu_to_be32(fbi->line_length * fbi->yres);
-	ret = of_set_property(node, "reg", cells, sizeof(cells[0]) * 2, 1);
+	of_write_number(cells, screen_base, addr_cells);
+	of_write_number(cells + addr_cells, fbi->screen_size, size_cells);
+
+	ret = of_set_property(node, "reg", cells, sizeof(cells[0]) * (addr_cells + size_cells), 1);
 	if (ret < 0)
 		return ret;
 

-- 
2.47.3

[PATCH 3/3] simplefb-fixup: add reserved memory-region entry for the simple-framebuffer

[Michael Grzeschik]

The modern way to describe an reserved memory region is to place an
entry in the reserved-memory nodes. Using the of_fixup_reserved_memory
this is simply done.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
---
 drivers/video/simplefb-fixup.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/video/simplefb-fixup.c b/drivers/video/simplefb-fixup.c
index 9b39e1ef46d84eed61242119251d340b44d59a6e..e20f2922445bddcb13a049b2581c4c632289d6ee 100644
--- a/drivers/video/simplefb-fixup.c
+++ b/drivers/video/simplefb-fixup.c
@@ -13,6 +13,7 @@
 #include <fb.h>
 #include <fcntl.h>
 #include <fs.h>
+#include <of.h>
 #include <init.h>
 #include <xfuncs.h>
 
@@ -93,6 +94,7 @@ static int simplefb_create_node(struct device_node *root,
 	phys_addr_t screen_base;
 	__be32 cells[4];
 	int addr_cells = 2, size_cells = 1, ret;
+	struct resource res = { };
 
 	of_property_read_u32(root, "#address-cells", &addr_cells);
 	of_property_read_u32(root, "#size-cells", &size_cells);
@@ -121,6 +123,12 @@ static int simplefb_create_node(struct device_node *root,
 	if (ret < 0)
 		return ret;
 
+	res.name = "simple-framebuffer";
+	res.flags |= IORESOURCE_BUSY;
+	resource_set_range(&res, screen_base, fbi->screen_size);
+
+	of_fixup_reserved_memory(root, &res);
+
 	cells[0] = cpu_to_be32(fbi->xres);
 	ret = of_set_property(node, "width", cells, sizeof(cells[0]), 1);
 	if (ret < 0)
@@ -140,8 +148,6 @@ static int simplefb_create_node(struct device_node *root,
 	if (ret < 0)
 		return ret;
 
-	of_add_reserve_entry(screen_base, screen_base + fbi->screen_size);
-
 	return of_property_write_string(node, "status", "okay");
 }
 

-- 
2.47.3

Re: [PATCH 0/3] simplefb-fixup: fixes for 64bit systems

[Sascha Hauer]

On Mon, 17 Nov 2025 22:29:25 +0100, Michael Grzeschik wrote:
> This series is containing fixes to hand over the simplefb to 64bit
> systems.
> 
> 

Applied, thanks!

[1/3] include: linux: ioport.h: port resource_set_range from linux
      https://git.pengutronix.de/cgit/barebox/commit/?id=543d3e804021 (link may not be stable)
[2/3] simplefb-fixup: depend res fields on root size-cells and addr-cells
      https://git.pengutronix.de/cgit/barebox/commit/?id=27fcc536a206 (link may not be stable)
[3/3] simplefb-fixup: add reserved memory-region entry for the simple-framebuffer
      https://git.pengutronix.de/cgit/barebox/commit/?id=8b6c55a48c64 (link may not be stable)

Best regards,
-- 
Sascha Hauer <s.hauer@pengutronix.de>