From: Alan Cox <alan@linux.intel.com>
Date: Sat, 20 Dec 2014 00:28:19 +0000 (+0000)
Subject: trs80, hd: Make the hard disk driver work and add swap
X-Git-Url: https://git.ndcode.org/public/gitweb.cgi?a=commitdiff_plain;h=69bb857a8d203e08cd9e8ff78dcecd43e605c336;p=FUZIX.git

trs80, hd: Make the hard disk driver work and add swap

With this we can now swap on the TRS80 platform and things seem to work
acceptably. Disk size and other properties are hardcoded in ways that will
need fixing. Partitioning support also needs to be added.
---

diff --git a/Kernel/platform-trs80/devhd.c b/Kernel/platform-trs80/devhd.c
index 5237a8b1..646ec8e5 100644
--- a/Kernel/platform-trs80/devhd.c
+++ b/Kernel/platform-trs80/devhd.c
@@ -7,8 +7,8 @@
 #include <printf.h>
 #include <devhd.h>
 
-__sfr __at 0xC0 hd_wpbits;
-__sfr __at 0xC1 hd_ctrl;
+__sfr __at 0xC0 hd_wpbits;	/* Write protect and IRQ (not used) */
+__sfr __at 0xC1 hd_ctrl;	/* Reset and enable bits */
 __sfr __at 0xC8 hd_data;
 __sfr __at 0xC9 hd_precomp;	/* W/O */
 __sfr __at 0xC9 hd_err;		/* R/O */
@@ -28,6 +28,12 @@ __sfr __at 0xCF hd_cmd;
 #define HDCMD_INIT	0x60	/* Ditto */
 #define HDCMD_SEEK	0x70
 
+#define HDCTRL_SOFTRESET	0x10
+#define HDCTRL_ENABLE		0x08
+#define HDCTRL_WAITENABLE	0x04
+
+#define HDSDH_ECC256		0x80
+
 /* Used by the asm helpers */
 uint8_t hd_page;
 
@@ -36,7 +42,7 @@ uint8_t hd_page;
 
 #define MAX_HD	4
 
-/* Wait for DRQ or an error */
+/* Wait for the drive to show ready */
 static uint8_t hd_waitready(void)
 {
 	uint8_t st;
@@ -97,7 +103,6 @@ static int hd_transfer(uint8_t minor, bool is_read, uint8_t rawflag)
 		dptr = (uint16_t)swapbase;
 		hd_page = swapproc->p_page;
 		block = swapblk;
-		kprintf("Swapping for page %x %d blocks\n", hd_page, nblock);
 	} else
 		goto bad2;
 
@@ -115,16 +120,20 @@ static int hd_transfer(uint8_t minor, bool is_read, uint8_t rawflag)
 
 	hd_precomp = 0x20;	/* For now, matches an ST506 */
 	hd_seccnt = 1;
-	sector = ((block & 15) << 1) + 1;
- 	hd_secnum = sector;
-	hd_cyllo = (block >> 6) & 0xFF;
-	hd_cylhi = (block >> 14) & 0xFF;
-	head = (block >> 4) & 3;
-
-	hd_precomp = 0;		/* FIXME */
-	hd_sdh = 0x80 | head | (minor << 3);
+	block <<= 1;		/* Into 256 byte blocks, limits us to 32MB
+				   so ought to FIXME */
 
 	while (ct < nblock) {
+		/* 32 sectors per track assumed for now */
+		sector = (block & 31) + 1;
+		head = (block >> 5) & 3;
+		/* Head next bits, plus drive */
+		hd_sdh = 0x80 | head | (minor << 3);
+		hd_secnum = sector;
+		/* cylinder bits */
+		hd_cyllo = (block >> 7) & 0xFF;
+		hd_cylhi = (block >> 15) & 0xFF;
+
 		for (tries = 0; tries < 4; tries++) {
 			/* issue the command */
 			hd_cmd = cmd;
@@ -136,11 +145,13 @@ static int hd_transfer(uint8_t minor, bool is_read, uint8_t rawflag)
 				/* Ready, no error ? */
 				if ((err & 0x41) == 0x40)
 					break;
-			}
+			} else
+				kprintf("hd%d: err %x\n", minor, err);
 
 			if (tries > 1) {
 				hd_cmd = HDCMD_RESTORE;
-				hd_waitready();
+				if (hd_waitready() & 1)
+					kprintf("hd%d: restore error %z\n", minor, err);
 			}
 		}
 		/* FIXME: should we try the other half and then bale out ? */
@@ -148,7 +159,7 @@ static int hd_transfer(uint8_t minor, bool is_read, uint8_t rawflag)
 			goto bad;
 		ct++;
 		dptr += 256;
-		hd_secnum = sector + 1;
+		block ++;
 	}
 	return 1;
 bad: