[Skiboot] [PATCH V2 3/7] libflash/blocklevel: add blocklevel flags.

[Cyril Bur]

It has become apparent that communication between blocklevel and its
backend may be necessarily, at least so that the backend can inform
blocklevel as to if an erase must be done before a write.

An erase before flag isn't strictly necessary as erases can be performed
regardless of whether they need to be or not, however, the caveat with that
is that when erases don't need to be performed, this is likely due to the
backend not having erase blocks and therefore it may be impossible to set a
sane value for erase blocks which would be used to erase before write.

This flag saves backends that don't need erases before write to have to lie
about an erase block size.

Signed-off-by: Cyril Bur <cyril.bur at au1.ibm.com>
---
 libflash/blocklevel.h | 5 +++++
 libflash/libflash.c   | 1 +
 2 files changed, 6 insertions(+)

diff --git a/libflash/blocklevel.h b/libflash/blocklevel.h
index fac05cd..2185ca7 100644
--- a/libflash/blocklevel.h
+++ b/libflash/blocklevel.h
@@ -23,6 +23,10 @@ struct bl_prot_range {
 	uint32_t len;
 };
 
+enum blocklevel_flags {
+	WRITE_NEED_ERASE = 1,
+};
+
 /*
  * libffs may be used with different backends, all should provide these for
  * libflash to get the information it needs
@@ -39,6 +43,7 @@ struct blocklevel_device {
 	 * Keep the erase mask so that blocklevel_erase() can do sanity checking
 	 */
 	uint32_t erase_mask;
+	enum blocklevel_flags flags;
 
 	struct bl_prot_range *ecc_prot;
 	int n_ecc_prot;
diff --git a/libflash/libflash.c b/libflash/libflash.c
index a142e17..55eafbe 100644
--- a/libflash/libflash.c
+++ b/libflash/libflash.c
@@ -838,6 +838,7 @@ bail:
 	c->bl.erase = &flash_erase;
 	c->bl.get_info = &flash_get_info;
 	c->bl.erase_mask = c->min_erase_mask;
+	c->bl.flags = WRITE_NEED_ERASE;
 
 	*bl = &(c->bl);
 	return 0;
-- 
2.4.3