lantiq: nand fixes

Signed-off-by: John Crispin <blogic@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@40372 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 137 insertions, 0 deletions

diff --git a/target/linux/lantiq/patches-3.10/0206-lantiq-nand-lock.patch b/target/linux/lantiq/patches-3.10/0206-lantiq-nand-lock.patch
new file mode 100644
index 0000000000..6e332b4bf9
--- /dev/null
+++ b/target/linux/lantiq/patches-3.10/0206-lantiq-nand-lock.patch
@@ -0,0 +1,137 @@
+From patchwork Wed Apr  2 19:38:52 2014
+Content-Type: text/plain; charset="utf-8"
+MIME-Version: 1.0
+Content-Transfer-Encoding: 7bit
+Subject: [OpenWrt-Devel,
+	4/7] lantiq: BT Home Hub 2B support - nand pci interference
+Date: Wed, 02 Apr 2014 18:38:52 -0000
+From: Ben Mulvihill <ben.mulvihill@gmail.com>
+X-Patchwork-Id: 5113
+Message-Id: <1396467532.31327.42.camel@merveille.lan>
+To: openwrt-devel@lists.openwrt.org
+
+Prevents interference between the xway nand driver and pci.
+
+(Based on work by Simon Hayes first published on www.psidoc.com and
+http://sourceforge.net/projects/hh2b4ever/)
+
+Signed-off-by: Ben Mulvihill <ben.mulvihill@gmail.com>
+
+---
+
+
+--- a/drivers/mtd/nand/xway_nand.c	2014-04-01 21:24:52.798612391 +0200
++++ a/drivers/mtd/nand/xway_nand.c	2014-04-01 21:20:33.924585096 +0200
+@@ -54,8 +54,27 @@
+ #define NAND_CON_CSMUX		(1 << 1)
+ #define NAND_CON_NANDM		1
+ 
++#define DANUBE_PCI_REG32( addr )    (*(volatile u32 *)(addr))
++#define PCI_CR_PR_OFFSET	    (KSEG1+0x1E105400)
++#define PCI_CR_PC_ARB		    (PCI_CR_PR_OFFSET + 0x0080)
++
+ static u32 xway_latchcmd;
+ 
++/*
++ * req_mask provides a mechanism to prevent interference between
++ * nand and pci (probably only relevant for the BT Home Hub 2B).
++ * Setting it causes the corresponding pci req pins to be masked
++ * during nand access, and also moves ebu locking from the read/write
++ * functions to the chip select function to ensure that the whole
++ * operation runs with interrupts disabled.
++ * In addition it switches on some extra waiting in xway_cmd_ctrl().
++ * This seems to be necessary if the ebu_cs1 pin has open-drain disabled,
++ * which in turn seems to be necessary for the nor chip to be recognised
++ * reliably, on a board (Home Hub 2B again) which has both nor and nand.
++ */
++
++static __be32 req_mask = 0;
++
+ static void xway_reset_chip(struct nand_chip *chip)
+ {
+ 	unsigned long nandaddr = (unsigned long) chip->IO_ADDR_W;
+@@ -86,12 +105,24 @@ static void xway_select_chip(struct mtd_
+ 	case -1:
+ 		ltq_ebu_w32_mask(NAND_CON_CE, 0, EBU_NAND_CON);
+ 		ltq_ebu_w32_mask(NAND_CON_NANDM, 0, EBU_NAND_CON);
++
++		if (req_mask) {
++			/* Unmask all external PCI request */
++			DANUBE_PCI_REG32(PCI_CR_PC_ARB) &= ~(req_mask << 16);
++		}
+ 		spin_unlock_irqrestore(&ebu_lock, csflags);
++
+ 		break;
+ 	case 0:
+ 		spin_lock_irqsave(&ebu_lock, csflags);
++		if (req_mask) {
++			/* Mask all external PCI request */
++			DANUBE_PCI_REG32(PCI_CR_PC_ARB) |= (req_mask << 16);
++		}
++
+ 		ltq_ebu_w32_mask(0, NAND_CON_NANDM, EBU_NAND_CON);
+ 		ltq_ebu_w32_mask(0, NAND_CON_CE, EBU_NAND_CON);
++
+ 		break;
+ 	default:
+ 		BUG();
+@@ -103,6 +134,12 @@ static void xway_cmd_ctrl(struct mtd_inf
+ 	struct nand_chip *this = mtd->priv;
+ 	unsigned long nandaddr = (unsigned long) this->IO_ADDR_W;
+ 
++	if (req_mask) {
++		if (cmd != NAND_CMD_STATUS)
++			ltq_ebu_w32(EBU_NAND_WAIT, 0); /* Clear nand ready */
++	}
++
++
+ 	if (ctrl & NAND_CTRL_CHANGE) {
+ 		if (ctrl & NAND_CLE)
+ 			xway_latchcmd = NAND_WRITE_CMD;
+@@ -115,6 +152,24 @@ static void xway_cmd_ctrl(struct mtd_inf
+ 		while ((ltq_ebu_r32(EBU_NAND_WAIT) & NAND_WAIT_WR_C) == 0)
+ 			;
+ 	}
++
++	if (req_mask) {
++	       /*
++		* program and erase have their own busy handlers
++		* status and sequential in needs no delay
++		*/
++		switch (cmd) {
++			case NAND_CMD_ERASE1:
++			case NAND_CMD_SEQIN:
++			case NAND_CMD_STATUS:
++			case NAND_CMD_READID:
++			return;
++		}
++
++		/* wait until command is processed */
++		while ((ltq_ebu_r32(EBU_NAND_WAIT) & NAND_WAIT_RD) == 0)
++			;
++	}
+ }
+ 
+ static int xway_dev_ready(struct mtd_info *mtd)
+@@ -157,6 +212,8 @@ static int xway_nand_probe(struct platfo
+ {
+ 	struct nand_chip *this = platform_get_drvdata(pdev);
+ 	unsigned long nandaddr = (unsigned long) this->IO_ADDR_W;
++	const __be32 *req_mask_ptr = of_get_property(pdev->dev.of_node,
++					"req-mask", NULL);
+ 	const __be32 *cs = of_get_property(pdev->dev.of_node,
+ 					"lantiq,cs", NULL);
+ 	u32 cs_flag = 0;
+@@ -165,6 +222,12 @@ static int xway_nand_probe(struct platfo
+ 	if (cs && (*cs == 1))
+ 		cs_flag = NAND_CON_IN_CS1 | NAND_CON_OUT_CS1;
+ 
++	/*
++	 * Load the PCI req lines to mask from the device tree. If the
++	 * property is not present, setting req_mask to 0 disables masking.
++	 */
++	req_mask = (req_mask_ptr ? *req_mask_ptr : 0);
++
+ 	/* setup the EBU to run in NAND mode on our base addr */
+ 	ltq_ebu_w32(CPHYSADDR(nandaddr)
+ 		| ADDSEL1_MASK(3) | ADDSEL1_REGEN, EBU_ADDSEL1);