From 7f05e20b989ac33c9c0f8c2028ec0a566493548f Mon Sep 17 00:00:00 2001 From: Andrea della Porta Date: Sun, 24 Nov 2024 11:05:37 +0100 Subject: [PATCH] of: address: Preserve the flags portion on 1:1 dma-ranges mapping A missing or empty dma-ranges in a DT node implies a 1:1 mapping for dma translations. In this specific case, the current behaviour is to zero out the entire specifier so that the translation could be carried on as an offset from zero. This includes address specifier that has flags (e.g. PCI ranges). Once the flags portion has been zeroed, the translation chain is broken since the mapping functions will check the upcoming address specifier against mismatching flags, always failing the 1:1 mapping and its entire purpose of always succeeding. Set to zero only the address portion while passing the flags through. Fixes: dbbdee94734b ("of/address: Merge all of the bus translation code") Cc: stable@vger.kernel.org Signed-off-by: Andrea della Porta Tested-by: Herve Codina Link: https://lore.kernel.org/r/e51ae57874e58a9b349c35e2e877425ebc075d7a.1732441813.git.andrea.porta@suse.com Signed-off-by: Rob Herring (Arm) --- drivers/of/address.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/of/address.c b/drivers/of/address.c index c5b925ac469f1..5b7ee3ed5296b 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -459,7 +459,8 @@ static int of_translate_one(const struct device_node *parent, const struct of_bu } if (ranges == NULL || rlen == 0) { offset = of_read_number(addr, na); - memset(addr, 0, pna * 4); + /* set address to zero, pass flags through */ + memset(addr + pbus->flag_cells, 0, (pna - pbus->flag_cells) * 4); pr_debug("empty ranges; 1:1 translation\n"); goto finish; } -- 2.47.2