1 files changed, 134 insertions, 0 deletions
diff --git a/os/port/flashcfi16.c b/os/port/flashcfi16.c
new file mode 100644
index 00000000..3c22f475
--- /dev/null
+++ b/os/port/flashcfi16.c
@@ -0,0 +1,134 @@
+#include	"u.h"
+#include	"../port/lib.h"
+#include	"mem.h"
+#include	"dat.h"
+#include	"fns.h"
+#include	"io.h"
+#include	"../port/error.h"
+
+#include	"../port/flashif.h"
+
+/*
+ * Common Flash Interface (1x16 and 2x16)
+ */
+
+/* interleaved flash has chips at even and odd word addresses */
+#define	I(x)	(((x)<<24)|((x)<<16)|((x)<<8)|(x))
+
+enum {
+	ReadArray = I(0xFF),
+	ReadQuery = I(0x98),
+};
+
+#include "flashintel"
+
+static int
+cfiget1(Flash *f, ulong a)
+{
+	ulong v;
+
+	v = flashget(f, a);
+//iprint("%.8lux->%.4ux\n", a, v);
+	if(f->width == 2 && v == 0xFFFF)
+		return 0;	/* get this on old, partially-conforming CFI */
+	return v & 0xFF;
+}
+
+static int
+cfiget2(Flash *f, ulong i)
+{
+	return (cfiget1(f, i+1)<<8) | cfiget1(f, i);
+}
+
+static int
+cfiquery(Flash *f)
+{
+	Flashregion *r;
+	ulong addr;
+	int i;
+
+	flashput(f, 0x55, ReadQuery);
+	if(!(cfiget1(f, 0x10) == 'Q' && cfiget1(f, 0x11) == 'R' && cfiget1(f, 0x12) == 'Y'))	/* TO DO: detect interleave */
+		return 0;
+	f->alg = cfiget2(f, 0x13);
+	i = cfiget1(f, 0x27);
+	if(i > 0 && i < 32)
+		i = 1<<i;
+	else
+		i = 0;
+	f->devsize = i;
+	f->size = f->devsize;
+	if(f->interleave)
+		f->size *= 2;
+	i = cfiget2(f, 0x2A);
+	if(i > 0 && i < 32)
+		i = 1<<i;
+	else
+		i = 0;
+	f->maxwb = i;
+	f->nr = cfiget1(f, 0x2C);
+	if(f->nr != 0){
+		addr = 0;
+		for(i=0; i<f->nr; i++){
+			r = &f->regions[i];
+			r->n = cfiget2(f, 0x2D+4*i)+1;
+			r->erasesize = cfiget2(f, 0x2D+2+4*i)*256;
+			if(r->erasesize == 0)
+				r->erasesize = 128;
+			if(f->interleave)
+				r->erasesize *= 2;	/* TO DO */
+			r->start = addr;
+			r->end = r->start + r->n*r->erasesize;
+		}
+		if(1){
+			iprint("cfi: devsize=%lud maxwb=%d\n", f->devsize, f->maxwb);
+			for(i=0; i<f->nr; i++){
+				r = &f->regions[i];
+				iprint("flash %d: %d %lud %8.8lux %8.8lux\n", i, r->n, r->erasesize, r->start, r->end);
+			}
+		}
+	}else{
+		f->nr = 1;
+		f->regions[0] = (Flashregion){1, 0, f->devsize, f->devsize, 0};
+	}
+	return 1;
+}
+
+static int
+reset(Flash *f)
+{
+	if(f->xip)
+		return -1;	/* can't use this interface if executing from flash */
+	if(f->width == 0)
+		f->width = 2;
+	if(!cfiquery(f) || f->alg != 1 && f->alg != 3){
+		/* apparently not CFI: try to reset to read mode before return */
+		flashput(f, 0x55, ClearStatus);
+		flashput(f, 0x55, ReadArray);
+		return -1;
+	}
+	f->cmask = 0x00FF00FF;
+	flashput(f, 0x55, ClearStatus);
+	flashput(f, 0x55, ReadID);
+	f->id = cfiget1(f, 0x00);
+	f->devid = cfiget1(f, 0x01);
+	flashput(f, 0x55, ClearStatus);
+	flashput(f, 0x55, ReadArray);
+	if(f->width == 2){
+		f->cmask = 0x00FF;
+		f->write = intelwrite2;
+	}else{
+		f->cmask = 0x00FF00FF;
+		f->write = intelwrite4;
+	}
+	f->erasezone = intelerase;
+	f->suspend = nil;
+	f->resume = nil;
+	return 0;
+}
+
+void
+flashcfi16link(void)
+{
+	addflashcard("cfi16", reset);
+}