From d20ec7529236a2fcdb2d856fc0bd80b409a217fc Mon Sep 17 00:00:00 2001 From: Heiko Stuebner Date: Thu, 7 Jul 2022 01:15:36 +0200 Subject: riscv: implement cache-management errata for T-Head SoCs The T-Head C906 and C910 implement a scheme for handling cache operations different from the generic Zicbom extension. Add an errata for it next to the generic dma coherency ops. Reviewed-by: Samuel Holland Tested-by: Samuel Holland Reviewed-by: Guo Ren Signed-off-by: Heiko Stuebner Link: https://lore.kernel.org/r/20220706231536.2041855-5-heiko@sntech.de Signed-off-by: Palmer Dabbelt --- arch/riscv/errata/thead/errata.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'arch/riscv/errata') diff --git a/arch/riscv/errata/thead/errata.c b/arch/riscv/errata/thead/errata.c index b37b6fedd53b..202c83f677b2 100644 --- a/arch/riscv/errata/thead/errata.c +++ b/arch/riscv/errata/thead/errata.c @@ -27,6 +27,23 @@ static bool errata_probe_pbmt(unsigned int stage, return false; } +static bool errata_probe_cmo(unsigned int stage, + unsigned long arch_id, unsigned long impid) +{ +#ifdef CONFIG_ERRATA_THEAD_CMO + if (arch_id != 0 || impid != 0) + return false; + + if (stage == RISCV_ALTERNATIVES_EARLY_BOOT) + return false; + + riscv_noncoherent_supported(); + return true; +#else + return false; +#endif +} + static u32 thead_errata_probe(unsigned int stage, unsigned long archid, unsigned long impid) { @@ -35,6 +52,9 @@ static u32 thead_errata_probe(unsigned int stage, if (errata_probe_pbmt(stage, archid, impid)) cpu_req_errata |= (1U << ERRATA_THEAD_PBMT); + if (errata_probe_cmo(stage, archid, impid)) + cpu_req_errata |= (1U << ERRATA_THEAD_CMO); + return cpu_req_errata; } -- cgit