From 99e75a37bd0af8eb8a0560f48091672b1b6d9218 Mon Sep 17 00:00:00 2001 From: Alex Elder Date: Thu, 18 Mar 2021 13:59:30 -0500 Subject: [PATCH] net: ipa: relax 64-bit build requirement We currently assume the IPA driver is built only for a 64 bit kernel. When this constraint was put in place it eliminated some do_div() calls, replacing them with the "/" and "%" operators. We now only use these operations on u32 and size_t objects. In a 32-bit kernel build, size_t will be 32 bits wide, so there remains no reason to use do_div() for divide and modulo. A few recent commits also fix some code that assumes that DMA addresses are 64 bits wide. With that, we can get rid of the 64-bit build requirement. Signed-off-by: Alex Elder Signed-off-by: David S. Miller --- drivers/net/ipa/Kconfig | 2 +- drivers/net/ipa/ipa_main.c | 10 ++++++++-- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/net/ipa/Kconfig b/drivers/net/ipa/Kconfig index b68f1289..90a9026 100644 --- a/drivers/net/ipa/Kconfig +++ b/drivers/net/ipa/Kconfig @@ -1,6 +1,6 @@ config QCOM_IPA tristate "Qualcomm IPA support" - depends on 64BIT && NET && QCOM_SMEM + depends on NET && QCOM_SMEM depends on ARCH_QCOM || COMPILE_TEST depends on QCOM_RPROC_COMMON || (QCOM_RPROC_COMMON=n && COMPILE_TEST) select QCOM_MDT_LOADER if ARCH_QCOM diff --git a/drivers/net/ipa/ipa_main.c b/drivers/net/ipa/ipa_main.c index 97c1b55..d354e3e 100644 --- a/drivers/net/ipa/ipa_main.c +++ b/drivers/net/ipa/ipa_main.c @@ -735,8 +735,14 @@ MODULE_DEVICE_TABLE(of, ipa_match); static void ipa_validate_build(void) { #ifdef IPA_VALIDATE - /* We assume we're working on 64-bit hardware */ - BUILD_BUG_ON(!IS_ENABLED(CONFIG_64BIT)); + /* At one time we assumed a 64-bit build, allowing some do_div() + * calls to be replaced by simple division or modulo operations. + * We currently only perform divide and modulo operations on u32, + * u16, or size_t objects, and of those only size_t has any chance + * of being a 64-bit value. (It should be guaranteed 32 bits wide + * on a 32-bit build, but there is no harm in verifying that.) + */ + BUILD_BUG_ON(!IS_ENABLED(CONFIG_64BIT) && sizeof(size_t) != 4); /* Code assumes the EE ID for the AP is 0 (zeroed structure field) */ BUILD_BUG_ON(GSI_EE_AP != 0); -- 2.7.4