From: Nathan Lynch <nathanl@xxxxxxxxxxxxx> [ Upstream commit daa8ab59044610aa8ef2ee45a6c157b5e11635e9 ] The ibm,get-system-parameter RTAS function may return -2 or 990x, which indicate that the caller should try again. pseries_lpar_read_hblkrm_characteristics() ignores this, making it possible to incorrectly detect TLB block invalidation characteristics at boot. Move the RTAS call into a coventional rtas_busy_delay()-based loop. Signed-off-by: Nathan Lynch <nathanl@xxxxxxxxxxxxx> Fixes: 1211ee61b4a8 ("powerpc/pseries: Read TLB Block Invalidate Characteristics") Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20230125-b4-powerpc-rtas-queue-v3-3-26929c8cce78@xxxxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/powerpc/platforms/pseries/lpar.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c index 1c3ac0f663369..115d196560b8b 100644 --- a/arch/powerpc/platforms/pseries/lpar.c +++ b/arch/powerpc/platforms/pseries/lpar.c @@ -1433,22 +1433,22 @@ static inline void __init check_lp_set_hblkrm(unsigned int lp, void __init pseries_lpar_read_hblkrm_characteristics(void) { + const s32 token = rtas_token("ibm,get-system-parameter"); unsigned char local_buffer[SPLPAR_TLB_BIC_MAXLENGTH]; int call_status, len, idx, bpsize; if (!firmware_has_feature(FW_FEATURE_BLOCK_REMOVE)) return; - spin_lock(&rtas_data_buf_lock); - memset(rtas_data_buf, 0, RTAS_DATA_BUF_SIZE); - call_status = rtas_call(rtas_token("ibm,get-system-parameter"), 3, 1, - NULL, - SPLPAR_TLB_BIC_TOKEN, - __pa(rtas_data_buf), - RTAS_DATA_BUF_SIZE); - memcpy(local_buffer, rtas_data_buf, SPLPAR_TLB_BIC_MAXLENGTH); - local_buffer[SPLPAR_TLB_BIC_MAXLENGTH - 1] = '\0'; - spin_unlock(&rtas_data_buf_lock); + do { + spin_lock(&rtas_data_buf_lock); + memset(rtas_data_buf, 0, RTAS_DATA_BUF_SIZE); + call_status = rtas_call(token, 3, 1, NULL, SPLPAR_TLB_BIC_TOKEN, + __pa(rtas_data_buf), RTAS_DATA_BUF_SIZE); + memcpy(local_buffer, rtas_data_buf, SPLPAR_TLB_BIC_MAXLENGTH); + local_buffer[SPLPAR_TLB_BIC_MAXLENGTH - 1] = '\0'; + spin_unlock(&rtas_data_buf_lock); + } while (rtas_busy_delay(call_status)); if (call_status != 0) { pr_warn("%s %s Error calling get-system-parameter (0x%x)\n", -- 2.39.2