From e7985f43609c782132f8f5794ee6cc4cdb66ca75 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 29 May 2024 14:59:21 -0500 Subject: [PATCH] of: property: Fix fw_devlink handling of interrupt-map Commit d976c6f4b32c ("of: property: Add fw_devlink support for interrupt-map property") tried to do what it says on the tin, but failed on a couple of points: - it confuses bytes and cells. Not a huge deal, except when it comes to pointer arithmetic - it doesn't really handle anything but interrupt-maps that have their parent #address-cells set to 0 The combinations of the two leads to some serious fun on my M1 box, with plenty of WARN-ON() firing all over the shop, and amusing values being generated for interrupt specifiers. Having 2 versions of parsing code for "interrupt-map" was a bad idea. Now that the common parsing parts have been refactored into of_irq_parse_imap_parent(), rework the code here to use it instead and fix the pointer arithmetic. Note that the dependency will be a bit different than the original code when the interrupt-map points to another interrupt-map. In this case, the original code would resolve to the final interrupt controller. Now the dependency is the parent interrupt-map (which itself should have a dependency to the parent). It is possible that a node with an interrupt-map has no driver. Fixes: d976c6f4b32c ("of: property: Add fw_devlink support for interrupt-map property") Signed-off-by: Marc Zyngier Co-developed-by: Rob Herring (Arm) Cc: Saravana Kannan Tested-by: Marc Zyngier Tested-by: Anup Patel Link: https://lore.kernel.org/r/20240529-dt-interrupt-map-fix-v2-2-ef86dc5bcd2a@kernel.org Signed-off-by: Rob Herring (Arm) --- drivers/of/property.c | 30 ++++++++++-------------------- 1 file changed, 10 insertions(+), 20 deletions(-) diff --git a/drivers/of/property.c b/drivers/of/property.c index 1c83e68f805b..164d77cb9445 100644 --- a/drivers/of/property.c +++ b/drivers/of/property.c @@ -1306,10 +1306,10 @@ static struct device_node *parse_interrupts(struct device_node *np, static struct device_node *parse_interrupt_map(struct device_node *np, const char *prop_name, int index) { - const __be32 *imap, *imap_end, *addr; + const __be32 *imap, *imap_end; struct of_phandle_args sup_args; u32 addrcells, intcells; - int i, imaplen; + int imaplen; if (!IS_ENABLED(CONFIG_OF_IRQ)) return NULL; @@ -1322,33 +1322,23 @@ static struct device_node *parse_interrupt_map(struct device_node *np, addrcells = of_bus_n_addr_cells(np); imap = of_get_property(np, "interrupt-map", &imaplen); - if (!imap || imaplen <= (addrcells + intcells)) + imaplen /= sizeof(*imap); + if (!imap) return NULL; - imap_end = imap + imaplen; - while (imap < imap_end) { - addr = imap; - imap += addrcells; + imap_end = imap + imaplen; - sup_args.np = np; - sup_args.args_count = intcells; - for (i = 0; i < intcells; i++) - sup_args.args[i] = be32_to_cpu(imap[i]); - imap += intcells; + for (int i = 0; imap + addrcells + intcells + 1 < imap_end; i++) { + imap += addrcells + intcells; - /* - * Upon success, the function of_irq_parse_raw() returns - * interrupt controller DT node pointer in sup_args.np. - */ - if (of_irq_parse_raw(addr, &sup_args)) + imap = of_irq_parse_imap_parent(imap, imap_end - imap, &sup_args); + if (!imap) return NULL; - if (!index) + if (i == index) return sup_args.np; of_node_put(sup_args.np); - imap += sup_args.args_count + 1; - index--; } return NULL; -- 2.39.5