Commit 0ed1fe4a authored by Helge Deller's avatar Helge Deller
Browse files

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: default avatarHelge Deller <deller@gmx.de>
parent fd8d0ca2

arch/parisc/kernel/head.S

+12 −6
Original line number Diff line number Diff line
@@ -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 */

arch/parisc/kernel/smp.c

+6 −1
Original line number Diff line number Diff line
@@ -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();

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