From 2fcf414549a860fbab619df0be75c85ad0c8cd95 Mon Sep 17 00:00:00 2001
From: Zbigniew Bodek <zbb@FreeBSD.org>
Date: Tue, 18 Apr 2017 10:39:14 +0000
Subject: [PATCH] Optimize Armada38x low-level MBUS settings

Add early init handler, which comprises various internal
bus optimisations for Armada 38x SoC's. Magic values used
due to undocumented registers.

Submitted by:	Marcin Wojtas <mw@semihalf.com>,
		Arnaud Ysmal <arnaud.ysmal@stormshield.eu>
Obtained from: Semihalf, Stormshield
Sponsored by: Stormshield
Differential revision: https://reviews.freebsd.org/D10219
---
 sys/arm/mv/armada38x/armada38x.c | 45 ++++++++++++++++++++++++++++++++
 sys/arm/mv/mv_machdep.c          |  3 +++
 sys/arm/mv/mvreg.h               |  5 ++++
 3 files changed, 53 insertions(+)

diff --git a/sys/arm/mv/armada38x/armada38x.c b/sys/arm/mv/armada38x/armada38x.c
index ae4d459ec774..ebb9fdc720e5 100644
--- a/sys/arm/mv/armada38x/armada38x.c
+++ b/sys/arm/mv/armada38x/armada38x.c
@@ -41,6 +41,7 @@ __FBSDID("$FreeBSD$");
 int armada38x_open_bootrom_win(void);
 int armada38x_scu_enable(void);
 int armada38x_win_set_iosync_barrier(void);
+int armada38x_mbus_optimization(void);
 
 uint32_t
 get_tclk(void)
@@ -114,6 +115,50 @@ armada38x_open_bootrom_win(void)
 	return (rv);
 }
 
+int
+armada38x_mbus_optimization(void)
+{
+	bus_space_handle_t vaddr_iowind;
+	int rv;
+
+	rv = bus_space_map(fdtbus_bs_tag, (bus_addr_t)MV_MBUS_CTRL_BASE,
+	    MV_MBUS_CTRL_REGS_LEN, 0, &vaddr_iowind);
+	if (rv != 0)
+		return (rv);
+
+	/*
+	 * MBUS Units Priority Control Register - Prioritize XOR,
+	 * PCIe and GbEs (ID=4,6,3,7,8) DRAM access
+	 * GbE is High and others are Medium.
+	 */
+	bus_space_write_4(fdtbus_bs_tag, vaddr_iowind, 0, 0x19180);
+
+	/*
+	 * Fabric Units Priority Control Register -
+	 * Prioritize CPUs requests.
+	 */
+	bus_space_write_4(fdtbus_bs_tag, vaddr_iowind, 0x4, 0x3000A);
+
+	/*
+	 * MBUS Units Prefetch Control Register -
+	 * Pre-fetch enable for all IO masters.
+	 */
+	bus_space_write_4(fdtbus_bs_tag, vaddr_iowind, 0x8, 0xFFFF);
+
+	/*
+	 * Fabric Units Prefetch Control Register -
+	 * Enable the CPUs Instruction and Data prefetch.
+	 */
+	bus_space_write_4(fdtbus_bs_tag, vaddr_iowind, 0xc, 0x303);
+
+	bus_space_barrier(fdtbus_bs_tag, vaddr_iowind, 0, MV_MBUS_CTRL_REGS_LEN,
+	    BUS_SPACE_BARRIER_WRITE);
+
+	bus_space_unmap(fdtbus_bs_tag, vaddr_iowind, MV_MBUS_CTRL_REGS_LEN);
+
+	return (rv);
+}
+
 int
 armada38x_scu_enable(void)
 {
diff --git a/sys/arm/mv/mv_machdep.c b/sys/arm/mv/mv_machdep.c
index f4dc0e105a29..26f1ddfc0675 100644
--- a/sys/arm/mv/mv_machdep.c
+++ b/sys/arm/mv/mv_machdep.c
@@ -77,6 +77,7 @@ void armadaxp_l2_init(void);
 int armada38x_win_set_iosync_barrier(void);
 int armada38x_scu_enable(void);
 int armada38x_open_bootrom_win(void);
+int armada38x_mbus_optimization(void);
 #endif
 
 #define MPP_PIN_MAX		68
@@ -259,6 +260,8 @@ platform_late_init(void)
 	/* Set IO Sync Barrier bit for all Mbus devices */
 	if (armada38x_win_set_iosync_barrier() != 0)
 		printf("WARNING: could not map CPU Subsystem registers\n");
+	if (armada38x_mbus_optimization() != 0)
+		printf("WARNING: could not enable mbus optimization\n");
 	if (armada38x_scu_enable() != 0)
 		printf("WARNING: could not enable SCU\n");
 #ifdef SMP
diff --git a/sys/arm/mv/mvreg.h b/sys/arm/mv/mvreg.h
index 547a0648937d..275ad572133c 100644
--- a/sys/arm/mv/mvreg.h
+++ b/sys/arm/mv/mvreg.h
@@ -447,4 +447,9 @@
 #define	CPU_RESET_ASSERT	0x1
 #endif
 
+#if defined(SOC_MV_ARMADA38X)
+#define	MV_MBUS_CTRL_BASE	(MV_BASE + 0x20420)
+#define	MV_MBUS_CTRL_REGS_LEN	0x10
+#endif
+
 #endif /* _MVREG_H_ */