Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Jiaxun Yang <jiaxun.yang@flygoat.com>
To:     linux-mips@vger.kernel.org
Cc:     Jiaxun Yang <jiaxun.yang@flygoat.com>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        Huacai Chen <chenhc@lemote.com>,
        Paul Burton <paulburton@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Stephen Kitt <steve@sk2.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Serge Semin <fancer.lancer@gmail.com>,
        Anshuman Khandual <anshuman.khandual@arm.com>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Daniel Silsby <dansilsby@gmail.com>,
        Mike Rapoport <rppt@linux.ibm.com>,
        Paul Cercueil <paul@crapouillou.net>,
        Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Allison Randal <allison@lohutok.net>,
        Tiezhu Yang <yangtiezhu@loongson.cn>,
        John Garry <john.garry@huawei.com>,
        Wei Xu <xuwei5@hisilicon.com>, linux-kernel@vger.kernel.org
Subject: [PATCH 3/4] lib: logic_pio: Introduce MMIO_LOWER_RESERVED
Date:   Sun, 26 Apr 2020 19:47:36 +0800
Message-Id: <20200426114806.1176629-4-jiaxun.yang@flygoat.com>
In-Reply-To: <20200426114806.1176629-1-jiaxun.yang@flygoat.com>
References: <20200426114806.1176629-1-jiaxun.yang@flygoat.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

That would allow platforms reserve some lower address in PIO MMIO range
to deal with legacy drivers with hardcoded I/O ports that can't be
managed by logic_pio.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
---
 lib/logic_pio.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/logic_pio.c b/lib/logic_pio.c
index f511a99bb389..57fff1cb7063 100644
--- a/lib/logic_pio.c
+++ b/lib/logic_pio.c
@@ -20,6 +20,10 @@
 static LIST_HEAD(io_range_list);
 static DEFINE_MUTEX(io_range_mutex);
 
+#ifndef MMIO_LOWER_RESERVED
+#define MMIO_LOWER_RESERVED	0
+#endif
+
 /* Consider a kernel general helper for this */
 #define in_range(b, first, len)        ((b) >= (first) && (b) < (first) + (len))
 
@@ -36,7 +40,7 @@ int logic_pio_register_range(struct logic_pio_hwaddr *new_range)
 	struct logic_pio_hwaddr *range;
 	resource_size_t start;
 	resource_size_t end;
-	resource_size_t mmio_end = 0;
+	resource_size_t mmio_end = MMIO_LOWER_RESERVED;
 	resource_size_t iio_sz = MMIO_UPPER_LIMIT;
 	int ret = 0;
 
-- 
2.26.0.rc2