From 79b95d0045a1a1362bc14d54a3322ff96d59f426 Mon Sep 17 00:00:00 2001
From: "Justin C. Miller" <justin@devjustinian.com>
Date: Sun, 20 May 2018 17:59:08 -0700
Subject: [PATCH] Move FIS creation into make_command

---
 src/kernel/ahci/port.cpp | 25 +++++++++++--------------
 src/kernel/ahci/port.h   |  4 +++-
 2 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/src/kernel/ahci/port.cpp b/src/kernel/ahci/port.cpp
index 5316716..ef40970 100644
--- a/src/kernel/ahci/port.cpp
+++ b/src/kernel/ahci/port.cpp
@@ -204,7 +204,7 @@ port::stop_commands()
 }
 
 int
-port::make_command(size_t length)
+port::make_command(size_t length, fis_register_h2d **fis)
 {
 	int slot = -1;
 	uint32_t used_slots =
@@ -238,10 +238,11 @@ port::make_command(size_t length)
 
 	ent.flags = cmd_list_fis_size(sizeof(fis_register_h2d));
 
-	fis_register_h2d *fis = reinterpret_cast<fis_register_h2d *>(&cmdt.cmd_fis);
-	kutil::memset(fis, 0, sizeof(fis_register_h2d));
-	fis->type = fis_type::register_h2d;
-	fis->pm_port = 0x80; // set command register flag
+	fis_register_h2d *cfis = reinterpret_cast<fis_register_h2d *>(&cmdt.cmd_fis);
+	kutil::memset(cfis, 0, sizeof(fis_register_h2d));
+	cfis->type = fis_type::register_h2d;
+	cfis->pm_port = 0x80; // set command register flag
+	*fis = cfis;
 
 	size_t remaining = length;
 	for (int i = 0; i < max_prd_count; ++i) {
@@ -272,13 +273,13 @@ port::make_command(size_t length)
 int
 port::read_async(uint64_t offset, size_t length, void *dest)
 {
-	int slot = make_command(length);
+	fis_register_h2d *fis;
+	int slot = make_command(length, &fis);
 	if (slot < 0)
 		return 0;
 
 	cmd_table &cmdt = m_cmd_table[slot];
 
-	fis_register_h2d *fis = reinterpret_cast<fis_register_h2d *>(&cmdt.cmd_fis);
 	fis->command = ata_cmd::read_dma_ext;
 	fis->device = 0x40; // ATA8-ACS p.175
 
@@ -336,22 +337,18 @@ port::read(uint64_t offset, size_t length, void *dest)
 int
 port::identify_async()
 {
-	int slot = make_command(512);
+	fis_register_h2d *fis;
+	int slot = make_command(512, &fis);
 	if (slot < 0)
 		return 0;
 
-	cmd_table &cmdt = m_cmd_table[slot];
-
-	fis_register_h2d *fis = reinterpret_cast<fis_register_h2d *>(&cmdt.cmd_fis);
-	kutil::memset(fis, 0, sizeof(fis_register_h2d));
-	fis->type = fis_type::register_h2d;
-	fis->pm_port = 0x80; // set command register flag
 	fis->command = ata_cmd::identify;
 
 	m_pending[slot].type = command_type::identify;
 	m_pending[slot].offset = 0;
 	m_pending[slot].count = 0;
 	m_pending[slot].data = 0;
+
 	if(issue_command(slot))
 		return slot;
 	else
diff --git a/src/kernel/ahci/port.h b/src/kernel/ahci/port.h
index 68dfc81..8d1885f 100644
--- a/src/kernel/ahci/port.h
+++ b/src/kernel/ahci/port.h
@@ -10,6 +10,7 @@ namespace ahci {
 
 struct cmd_list_entry;
 struct cmd_table;
+struct fis_register_h2d;
 class hba;
 enum class sata_signature : uint32_t;
 enum class port_cmd : uint32_t;
@@ -92,8 +93,9 @@ private:
 
 	/// Initialize a command structure
 	/// \arg length  The number of bytes of data needed in the PRDs
+	/// \arg fis     [out] The FIS for this command
 	/// \returns     The index of the command slot, or -1 if none available
-	int make_command(size_t length);
+	int make_command(size_t length, fis_register_h2d **fis);
 
 	/// Send a constructed command to the hardware
 	/// \arg slot   The index of the command slot used