SLOF: Support PAPR NVRAM RTAS callsqemu-slof-20121018

BenH still need to ACK this though.

From: Nikunj A. Dadhania <nikunj@linux.vnet.ibm.com>

* Determines size of the flash using device tree.
* Provides nvram access functions for RTAS_NVRAM
* Allocates temporary buffer of nvram in SLOF code and use that in C.
  (sbrk not available)
* NVRAM_LENGTH is used at various places, make sure it is well guarded
  and also use dynamically determined size once an RTAS-NVRAM is
  found.
* Use NVRAM_LENGTH as a variable in case of RTAS_NVRAM, not very
  elegant though

Signed-off-by: Nikunj A. Dadhania <nikunj@linux.vnet.ibm.com>

--

Changelog from v1:
* #define cleanups suggested by Thomas/Benh
* Fix makefile which missed passing $FLAG for building llfw
* renamed vio-nvram.fs as rtas-nvram.fs

7 files changed, 111 insertions, 12 deletions

diff --git a/lib/libbases/libbases.code b/lib/libbases/libbases.code
index 7dc941d..45312e2 100644
--- a/lib/libbases/libbases.code
+++ b/lib/libbases/libbases.code
@@ -20,7 +20,7 @@ MIRP
 // : get-nvram-size ( -- size )
 PRIM(get_X2d_nvram_X2d_size)
 	PUSH;
-	TOS.u = NVRAM_LENGTH;
+	TOS.u = get_nvram_size();
 MIRP
 
 // : get-flash-base ( -- base )
diff --git a/lib/libbootmsg/bootmsg_lvl.S b/lib/libbootmsg/bootmsg_lvl.S
index 65cf0c3..2e4c135 100644
--- a/lib/libbootmsg/bootmsg_lvl.S
+++ b/lib/libbootmsg/bootmsg_lvl.S
@@ -158,7 +158,8 @@ ENTRY(bootmsg_setlevel)
 	andi.	r3, r3, 0x7F
 	add     r6,r3,r6        // address     |
 	stb     r4,0(r6)        // store level |_ stwbrx r4,r3,r6
-#ifndef DISABLE_NVRAM
+	
+#if !defined(DISABLE_NVRAM) && !defined(RTAS_NVRAM)
 	LOAD64(r6, SB_NVRAM_FWONLY_adr + 8 )
 	add	r6,r6,r3
 	stb     r4,0(r6)
@@ -167,7 +168,7 @@ ENTRY(bootmsg_setlevel)
 	blr
 
 ENTRY(bootmsg_nvupdate)
-#ifndef DISABLE_NVRAM
+#if !defined(DISABLE_NVRAM) && !defined(RTAS_NVRAM)
 	mflr	r10
 	LOAD64(r3, SB_NVRAM_FWONLY_adr)
 	lwz	r4, 0(r3)
diff --git a/lib/libhvcall/libhvcall.h b/lib/libhvcall/libhvcall.h
index 302e2a3..6e418ba 100644
--- a/lib/libhvcall/libhvcall.h
+++ b/lib/libhvcall/libhvcall.h
@@ -70,6 +70,20 @@ static inline long h_add_logical_lan_buffer(unsigned long unit_address,
 	return hv_generic(H_ADD_LOGICAL_LAN_BUFFER, unit_address, buffer);
 }
 
+#define HV_RTAS_MAX_ARGRET	5
+
+struct hv_rtas_call {
+	uint32_t token;
+	uint32_t nargs;
+	uint32_t nrets;
+	uint32_t argret[HV_RTAS_MAX_ARGRET];
+};
+
+static inline unsigned long h_rtas(struct hv_rtas_call *rtas_buf)
+{
+	return hv_generic(KVMPPC_H_RTAS, (unsigned long)rtas_buf);
+}
+
 extern unsigned long hv_logical_ci_load(unsigned long size, unsigned long addr);
 extern unsigned long hv_logical_ci_store(unsigned long size, unsigned long addr,
 					 unsigned long value);
diff --git a/lib/libnvram/libnvram.code b/lib/libnvram/libnvram.code
index f1fd414..723941d 100644
--- a/lib/libnvram/libnvram.code
+++ b/lib/libnvram/libnvram.code
@@ -276,4 +276,12 @@ PRIM(delete_X2d_nvram_X2d_partition)
 
 MIRP
 
-
+// ( fetch_token store_token size nvram-addr -- )
+PRIM(internal_X2d_nvram_X2d_init)
+	void *nvram_addr = TOS.a; POP;
+	uint32_t nvram_size = TOS.u; POP;
+	uint32_t store_token = TOS.u; POP;
+	long fetch_token = TOS.u; POP;
+
+	nvram_init(fetch_token, store_token, nvram_size, nvram_addr);
+MIRP
diff --git a/lib/libnvram/libnvram.in b/lib/libnvram/libnvram.in
index 33ab3bc..bbb20a8 100644
--- a/lib/libnvram/libnvram.in
+++ b/lib/libnvram/libnvram.in
@@ -39,3 +39,4 @@ cod(internal-add-env)
 cod(internal-del-env)
 cod(internal-set-env)
 
+cod(internal-nvram-init)
diff --git a/lib/libnvram/nvram.c b/lib/libnvram/nvram.c
index 048ec0f..2cb83dc 100644
--- a/lib/libnvram/nvram.c
+++ b/lib/libnvram/nvram.c
@@ -12,6 +12,7 @@
 
 #include "cache.h"
 #include "nvram.h"
+#include "../libhvcall/libhvcall.h"
 
 #include <stdio.h>
 #include <stdarg.h>
@@ -20,9 +21,38 @@
 #include <nvramlog.h>
 #include <byteorder.h>
 
+#ifdef RTAS_NVRAM
+static uint32_t fetch_token;
+static uint32_t store_token;
+static uint32_t NVRAM_LENGTH;
+static char *nvram_buffer; /* use buffer allocated by SLOF code */
+#else
 #ifndef NVRAM_LENGTH
 #define NVRAM_LENGTH	0x10000
 #endif
+/*
+ * This is extremely ugly, but still better than implementing 
+ * another sbrk() around it.
+ */
+static char nvram_buffer[NVRAM_LENGTH];
+#endif
+
+static uint8_t nvram_buffer_locked=0x00;
+
+void nvram_init(uint32_t _fetch_token, uint32_t _store_token, 
+		long _nvram_length, void* nvram_addr)
+{
+#ifdef RTAS_NVRAM
+	fetch_token = _fetch_token;
+	store_token = _store_token;
+	NVRAM_LENGTH = _nvram_length;
+	nvram_buffer = nvram_addr;
+
+	printf("\nNVRAM: size=%d, fetch=%x, store=%x\n", 
+	       NVRAM_LENGTH, fetch_token, store_token);
+#endif
+}
+
 
 void asm_cout(long Character,long UART,long NVRAM);
 
@@ -48,6 +78,46 @@ static volatile uint8_t nvram[NVRAM_LENGTH]; /* FAKE */
 		*pos = data;					\
 	}
 
+#elif defined(RTAS_NVRAM)
+
+static inline void nvram_fetch(unsigned int offset, void *buf, unsigned int len)
+{
+ 	struct hv_rtas_call rtas = {
+		.token = fetch_token,
+		.nargs = 3,
+		.nrets = 2,
+		.argret = { offset, (uint32_t)(unsigned long)buf, len },
+	};
+	h_rtas(&rtas);
+}
+
+static inline void nvram_store(unsigned int offset, void *buf, unsigned int len)
+{
+	struct hv_rtas_call rtas = {
+		.token = store_token,
+		.nargs = 3,
+		.nrets = 2,
+		.argret = { offset, (uint32_t)(unsigned long)buf, len },
+	};
+	h_rtas(&rtas);
+}
+
+#define nvram_access(type,size,name) 				\
+	type nvram_read_##name(unsigned int offset)		\
+	{							\
+		type val;					\
+		if (offset > (NVRAM_LENGTH - sizeof(type)))	\
+			return 0;				\
+		nvram_fetch(offset, &val, size / 8);		\
+		return val;					\
+	}							\
+	void nvram_write_##name(unsigned int offset, type data)	\
+	{							\
+		if (offset > (NVRAM_LENGTH - sizeof(type)))	\
+			return;					\
+		nvram_store(offset, &data, size / 8);		\
+	}
+
 #else	/* DISABLE_NVRAM */
 
 static volatile uint8_t *nvram = (volatile uint8_t *)SB_NVRAM_adr;
@@ -83,12 +153,7 @@ nvram_access(uint16_t, 16, word)
 nvram_access(uint32_t, 32, dword)
 nvram_access(uint64_t, 64, qword)
 
-/*
- * This is extremely ugly, but still better than implementing 
- * another sbrk() around it.
- */
-static char nvram_buffer[NVRAM_LENGTH];
-static uint8_t nvram_buffer_locked=0x00;
+
 
 /**
  * This function is a minimal abstraction for our temporary
@@ -184,7 +249,7 @@ static char * get_partition_name(int offset)
 	for (i=0; i<12; i++)
 		name[i]=nvram_read_byte(offset+4+i);
 
-	// DEBUG("name: \"%s\"\n", name);
+	DEBUG("name: \"%s\"\n", name);
 	return name;
 }
 
@@ -217,7 +282,7 @@ static int calc_used_nvram_space(void)
 		}
 
 		len=get_partition_len(walk);
-		// DEBUG("... part len=%x, %x\n", len, len*16);
+		DEBUG("... part len=%x, %x\n", len, len*16);
 
 		if(!len) {
 			/* If there's a partition type but no len, bail out.
@@ -546,6 +611,13 @@ void reset_nvram(void)
 
 void nvram_debug(void)
 {
+#ifndef RTAS_NVRAM
 	printf("\nNVRAM_BASE: %p\n", nvram);
 	printf("NVRAM_LEN: 0x%x\n", NVRAM_LENGTH);
+#endif
+}
+
+unsigned int get_nvram_size(void)
+{
+	return NVRAM_LENGTH;
 }
diff --git a/lib/libnvram/nvram.h b/lib/libnvram/nvram.h
index 1324809..fa6bdd4 100644
--- a/lib/libnvram/nvram.h
+++ b/lib/libnvram/nvram.h
@@ -60,6 +60,9 @@ int delete_nvram_partition(partition_t part);
 void reset_nvram(void);
 void wipe_nvram(void);
 void nvram_debug(void);
+void nvram_init(uint32_t store_token, uint32_t fetch_token,
+		long nv_size, void* nvram_addr);
+unsigned int get_nvram_size(void);
 
 /* envvar.c */
 char *get_env(partition_t part, char *envvar);