[PATCH v4.4 backport 13/16] powerpc/pseries: Query hypervisor for RFI flush settings
From: Michael Ellerman <mpe@ellerman.id.au>
Date: 2018-02-04 05:01:41
Also in:
stable
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
From: Michael Neuling <redacted> commit 8989d56878a7735dfdb234707a2fee6faf631085 upstream. A new hypervisor call is available which tells the guest settings related to the RFI flush. Use it to query the appropriate flush instruction(s), and whether the flush is required. Signed-off-by: Michael Neuling <redacted> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> --- arch/powerpc/platforms/pseries/setup.c | 37 +++++++++++++++++++++++++++++++++- 1 file changed, 36 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 36df46eaba24..dd2545fc9947 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c@@ -499,6 +499,39 @@ static void __init find_and_init_phbs(void) of_pci_check_probe_only(); } +static void pseries_setup_rfi_flush(void) +{ + struct h_cpu_char_result result; + enum l1d_flush_type types; + bool enable; + long rc; + + /* Enable by default */ + enable = true; + + rc = plpar_get_cpu_characteristics(&result); + if (rc == H_SUCCESS) { + types = L1D_FLUSH_NONE; + + if (result.character & H_CPU_CHAR_L1D_FLUSH_TRIG2) + types |= L1D_FLUSH_MTTRIG; + if (result.character & H_CPU_CHAR_L1D_FLUSH_ORI30) + types |= L1D_FLUSH_ORI; + + /* Use fallback if nothing set in hcall */ + if (types == L1D_FLUSH_NONE) + types = L1D_FLUSH_FALLBACK; + + if (!(result.behaviour & H_CPU_BEHAV_L1D_FLUSH_PR)) + enable = false; + } else { + /* Default to fallback if case hcall is not available */ + types = L1D_FLUSH_FALLBACK; + } + + setup_rfi_flush(types, enable); +} + static void __init pSeries_setup_arch(void) { set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT);
@@ -515,7 +548,9 @@ static void __init pSeries_setup_arch(void) fwnmi_init(); - /* By default, only probe PCI (can be overriden by rtas_pci) */ + pseries_setup_rfi_flush(); + + /* By default, only probe PCI (can be overridden by rtas_pci) */ pci_add_flags(PCI_PROBE_ONLY); /* Find and initialize PCI host bridges */
--
2.14.1