X86: uv: implement a gru_read_gpa kernel function
The BIOS has decided to store a pointer to the partition reserved page in
a scratch MMR. The GRU is only able to read an MMR using a vload
instruction. The gru_read_gpa() function will implemented.
Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Jack Steiner <steiner@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/misc/sgi-gru/gru_instructions.h b/drivers/misc/sgi-gru/gru_instructions.h
index 3c9c066..e033b6c 100644
--- a/drivers/misc/sgi-gru/gru_instructions.h
+++ b/drivers/misc/sgi-gru/gru_instructions.h
@@ -340,6 +340,19 @@
* - nelem and stride are in elements
* - tri0/tri1 is in bytes for the beginning of the data segment.
*/
+static inline void gru_vload_phys(void *cb, unsigned long gpa,
+ unsigned int tri0, int iaa, unsigned long hints)
+{
+ struct gru_instruction *ins = (struct gru_instruction *)cb;
+
+ ins->baddr0 = (long)gpa | ((unsigned long)iaa << 62);
+ ins->nelem = 1;
+ ins->tri0 = tri0;
+ ins->op1_stride = 1;
+ gru_start_instruction(ins, __opword(OP_VLOAD, 0, XTYPE_DW, iaa, 0,
+ CB_IMA(hints)));
+}
+
static inline void gru_vload(void *cb, unsigned long mem_addr,
unsigned int tri0, unsigned char xtype, unsigned long nelem,
unsigned long stride, unsigned long hints)
diff --git a/drivers/misc/sgi-gru/grukservices.c b/drivers/misc/sgi-gru/grukservices.c
index 766e21e..d2b149f 100644
--- a/drivers/misc/sgi-gru/grukservices.c
+++ b/drivers/misc/sgi-gru/grukservices.c
@@ -858,6 +858,29 @@
/* ---------------------- GRU DATA COPY FUNCTIONS ---------------------------*/
/*
+ * Load a DW from a global GPA. The GPA can be a memory or MMR address.
+ */
+int gru_read_gpa(unsigned long *value, unsigned long gpa)
+{
+ void *cb;
+ void *dsr;
+ int ret, iaa;
+
+ STAT(read_gpa);
+ if (gru_get_cpu_resources(GRU_NUM_KERNEL_DSR_BYTES, &cb, &dsr))
+ return MQE_BUG_NO_RESOURCES;
+ iaa = gpa >> 62;
+ gru_vload_phys(cb, gpa, gru_get_tri(dsr), iaa, IMA);
+ ret = gru_wait(cb);
+ if (ret == CBS_IDLE)
+ *value = *(unsigned long *)dsr;
+ gru_free_cpu_resources(cb, dsr);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(gru_read_gpa);
+
+
+/*
* Copy a block of data using the GRU resources
*/
int gru_copy_gpa(unsigned long dest_gpa, unsigned long src_gpa,
diff --git a/drivers/misc/sgi-gru/grukservices.h b/drivers/misc/sgi-gru/grukservices.h
index d60d34b..02aa94d 100644
--- a/drivers/misc/sgi-gru/grukservices.h
+++ b/drivers/misc/sgi-gru/grukservices.h
@@ -131,6 +131,20 @@
/*
+ * Read a GRU global GPA. Source can be located in a remote partition.
+ *
+ * Input:
+ * value memory address where MMR value is returned
+ * gpa source numalink physical address of GPA
+ *
+ * Output:
+ * 0 OK
+ * >0 error
+ */
+int gru_read_gpa(unsigned long *value, unsigned long gpa);
+
+
+/*
* Copy data using the GRU. Source or destination can be located in a remote
* partition.
*
diff --git a/drivers/misc/sgi-gru/gruprocfs.c b/drivers/misc/sgi-gru/gruprocfs.c
index 3f2375c..cf6b3e3 100644
--- a/drivers/misc/sgi-gru/gruprocfs.c
+++ b/drivers/misc/sgi-gru/gruprocfs.c
@@ -98,6 +98,7 @@
printstat(s, flush_tlb_gru_tgh);
printstat(s, flush_tlb_gru_zero_asid);
printstat(s, copy_gpa);
+ printstat(s, read_gpa);
printstat(s, mesq_receive);
printstat(s, mesq_receive_none);
printstat(s, mesq_send);
diff --git a/drivers/misc/sgi-gru/grutables.h b/drivers/misc/sgi-gru/grutables.h
index 46990bc..f7b553a 100644
--- a/drivers/misc/sgi-gru/grutables.h
+++ b/drivers/misc/sgi-gru/grutables.h
@@ -224,6 +224,7 @@
atomic_long_t flush_tlb_gru_zero_asid;
atomic_long_t copy_gpa;
+ atomic_long_t read_gpa;
atomic_long_t mesq_receive;
atomic_long_t mesq_receive_none;