# HG changeset patch
# User Jimi Xenidis <jimix@xxxxxxxxxxxxxx>
# Node ID e22cbd2ea1e4720b7853e4b05a4a9cdda2bff348
# Parent 91ee784bc36703985d5e841d18d65a4151666c57
[XEN][POWERPC] SCOM access is fully known and working
Signed-off-by: Jimi Xenidis <jimix@xxxxxxxxxxxxxx>
---
xen/arch/powerpc/powerpc64/ppc970_scom.c | 151 +++++++++++++++++++++----------
1 files changed, 104 insertions(+), 47 deletions(-)
diff -r 91ee784bc367 -r e22cbd2ea1e4 xen/arch/powerpc/powerpc64/ppc970_scom.c
--- a/xen/arch/powerpc/powerpc64/ppc970_scom.c Wed Sep 20 15:25:27 2006 -0500
+++ b/xen/arch/powerpc/powerpc64/ppc970_scom.c Thu Sep 21 07:36:17 2006 -0400
@@ -22,33 +22,13 @@
#include <xen/types.h>
#include <xen/lib.h>
#include <xen/console.h>
+#include <xen/errno.h>
+#include <asm/delay.h>
#define SPRN_SCOMC 276
#define SPRN_SCOMD 277
-
-static inline void mtscomc(ulong scomc)
-{
- __asm__ __volatile__ ("mtspr %1, %0" : : "r" (scomc), "i"(SPRN_SCOMC));
-}
-
-static inline ulong mfscomc(void)
-{
- ulong scomc;
- __asm__ __volatile__ ("mfspr %0, %1" : "=r" (scomc): "i"(SPRN_SCOMC));
- return scomc;
-}
-
-static inline void mtscomd(ulong scomd)
-{
- __asm__ __volatile__ ("mtspr %1, %0" : : "r" (scomd), "i"(SPRN_SCOMD));
-}
-
-static inline ulong mfscomd(void)
-{
- ulong scomd;
- __asm__ __volatile__ ("mfspr %0, %1" : "=r" (scomd): "i"(SPRN_SCOMD));
- return scomd;
-}
+#define SCOMC_READ 1
+#define SCOMC_WRITE (!(SCOMC_READ))
union scomc {
struct scomc_bits {
@@ -68,50 +48,127 @@ union scomc {
};
-static inline ulong read_scom(ulong addr)
+static inline int read_scom(uint addr, ulong *d)
{
union scomc c;
- ulong d;
+ ulong flags;
- c.word = 0;
- c.bits.addr = addr;
- c.bits.RW = 0;
+ /* drop the low 8bits (including parity) */
+ addr >>= 8;
- mtscomc(c.word);
- d = mfscomd();
- c.word = mfscomc();
- if (c.bits.failure)
- panic("scom status: 0x%016lx\n", c.word);
+ /* these give iface errors because the address is ambiguous after
+ * the above bit dropping */
+ BUG_ON(addr == 0x8000);
- return d;
+ for (;;) {
+ c.word = 0;
+ c.bits.addr = addr;
+ c.bits.RW = SCOMC_READ;
+
+ local_irq_save(flags);
+ asm volatile (
+ "sync \n\t"
+ "mtspr %2, %0 \n\t"
+ "isync \n\t"
+ "mfspr %1, %3 \n\t"
+ "isync \n\t"
+ "mfspr %0, %2 \n\t"
+ "isync \n\t"
+ : "+r" (c.word), "=r" (*d)
+ : "i"(SPRN_SCOMC), "i"(SPRN_SCOMD));
+
+ local_irq_restore(flags);
+ /* WARNING! older 970s (pre FX) shift the bits right 1 position */
+
+ if (!c.bits.failure)
+ return 0;
+
+ /* deal with errors */
+ /* has SCOM been disabled? */
+ if (c.bits.disabled)
+ return -ENOSYS;
+
+ /* we were passed a bad addr return -1 */
+ if (c.bits.addr_error)
+ return -EINVAL;
+
+ /* this is way bad and we will checkstop soon */
+ BUG_ON(c.bits.proto_error);
+
+ if (c.bits.iface_error)
+ udelay(10);
+ }
}
-static inline void write_scom(ulong addr, ulong val)
+static inline int write_scom(uint addr, ulong d)
{
union scomc c;
+ ulong flags;
- c.word = 0;
- c.bits.addr = addr;
- c.bits.RW = 1;
+ /* drop the low 8bits (including parity) */
+ addr >>= 8;
- mtscomd(val);
- mtscomc(c.word);
- c.word = mfscomc();
- if (c.bits.failure)
- panic("scom status: 0x%016lx\n", c.word);
+ /* these give iface errors because the address is ambiguous after
+ * the above bit dropping */
+ BUG_ON(addr == 0x8000);
+
+ for (;;) {
+ c.word = 0;
+ c.bits.addr = addr;
+ c.bits.RW = SCOMC_WRITE;
+
+ local_irq_save(flags);
+ asm volatile(
+ "sync \n\t"
+ "mtspr %3, %1 \n\t"
+ "isync \n\t"
+ "mtspr %2, %0 \n\t"
+ "isync \n\t"
+ "mfspr %0, %2 \n\t"
+ "isync \n\t"
+ : "+r" (c.word)
+ : "r" (d), "i"(SPRN_SCOMC), "i"(SPRN_SCOMD));
+ local_irq_restore(flags);
+
+ if (!c.bits.failure)
+ return 0;
+
+ /* has SCOM been disabled? */
+ if (c.bits.disabled)
+ return -ENOSYS;
+
+ /* we were passed a bad addr return -1 */
+ if (c.bits.addr_error)
+ return -EINVAL;
+
+ /* this is way bad and we will checkstop soon */
+ BUG_ON(c.bits.proto_error);
+
+ /* check for iface and retry */
+ if (c.bits.iface_error)
+ udelay(10);
+ }
}
+/* SCOMC addresses are 16bit but we are given 24 bits in the
+ * books. The low oerder 8 bits are some kinda parity thin and should
+ * be ignored */
#define SCOM_AMCS_REG 0x022601
#define SCOM_AMCS_AND_MASK 0x022700
#define SCOM_AMCS_OR_MASK 0x022800
#define SCOM_CMCE 0x030901
#define SCOM_PMCR 0x400801
+#define SCOM_PTSR 0x408001
+
+/* cannot access these since only top 16bits are considered */
+#define SCOM_STATUS 0x800003
void cpu_scom_init(void)
{
-#ifdef not_yet
+ ulong val;
console_start_sync();
- printk("scom PMCR: 0x%016lx\n", read_scom(SCOM_PMCR));
+ if (!read_scom(SCOM_PTSR, &val))
+ printk("SCOM PTSR: 0x%016lx\n", val);
+
console_end_sync();
-#endif
}
_______________________________________________
Xen-ppc-devel mailing list
Xen-ppc-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-ppc-devel
|
Home