From 0ed1fe4ad394e54783bbffa84102faf435661a2e Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Fri, 12 Jan 2018 22:51:22 +0100 Subject: [PATCH] parisc: Check if secondary CPUs want own PDC calls The architecture specification says (for 64-bit systems): PDC is a per processor resource, and operating system software must be prepared to manage separate pointers to PDCE_PROC for each processor. The address of PDCE_PROC for the monarch processor is stored in the Page Zero location MEM_PDC. The address of PDCE_PROC for each non-monarch processor is passed in gr26 when PDCE_RESET invokes OS_RENDEZ. Currently we still use one PDC for all CPUs, but in case we face a machine which is following the specification let's warn about it. Signed-off-by: Helge Deller --- arch/parisc/kernel/head.S | 18 ++++++++++++------ arch/parisc/kernel/smp.c | 7 ++++++- 2 files changed, 18 insertions(+), 7 deletions(-) diff --git a/arch/parisc/kernel/head.S b/arch/parisc/kernel/head.S index bbbe360b458f..fbb4e43fda05 100644 --- a/arch/parisc/kernel/head.S +++ b/arch/parisc/kernel/head.S @@ -138,6 +138,16 @@ $pgt_fill_loop: std %dp,0x18(%r10) #endif +#ifdef CONFIG_64BIT + /* Get PDCE_PROC for monarch CPU. */ +#define MEM_PDC_LO 0x388 +#define MEM_PDC_HI 0x35C + ldw MEM_PDC_LO(%r0),%r3 + ldw MEM_PDC_HI(%r0),%r10 + depd %r10, 31, 32, %r3 /* move to upper word */ +#endif + + #ifdef CONFIG_SMP /* Set the smp rendezvous address into page zero. ** It would be safer to do this in init_smp_config() but @@ -196,12 +206,6 @@ common_stext: ** Someday, palo might not do this for the Monarch either. */ 2: -#define MEM_PDC_LO 0x388 -#define MEM_PDC_HI 0x35C - ldw MEM_PDC_LO(%r0),%r3 - ldw MEM_PDC_HI(%r0),%r6 - depd %r6, 31, 32, %r3 /* move to upper word */ - mfctl %cr30,%r6 /* PCX-W2 firmware bug */ ldo PDC_PSW(%r0),%arg0 /* 21 */ @@ -268,6 +272,8 @@ $install_iva: aligned_rfi: pcxt_ssm_bug + copy %r3, %arg0 /* PDCE_PROC for smp_callin() */ + rsm PSW_SM_QUIET,%r0 /* off troublesome PSW bits */ /* Don't need NOPs, have 8 compliant insn before rfi */ diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c index 30c28ab14540..4065b5e48c9d 100644 --- a/arch/parisc/kernel/smp.c +++ b/arch/parisc/kernel/smp.c @@ -292,10 +292,15 @@ smp_cpu_init(int cpunum) * Slaves start using C here. Indirectly called from smp_slave_stext. * Do what start_kernel() and main() do for boot strap processor (aka monarch) */ -void __init smp_callin(void) +void __init smp_callin(unsigned long pdce_proc) { int slave_id = cpu_now_booting; +#ifdef CONFIG_64BIT + WARN_ON(((unsigned long)(PAGE0->mem_pdc_hi) << 32 + | PAGE0->mem_pdc) != pdce_proc); +#endif + smp_cpu_init(slave_id); preempt_disable(); -- 2.30.2