sh: Fix up multi-resource mapping for SH7786 PCIe.

This reworks some of the SH7786 PCIe initialization code to dynamically
setup and size the various resource windows, as opposed to the original
code that simply wired in a couple of them statically.

At the same time, we tidy up the initialization code a bit, kill off some
read-only register twiddling that was gleaned from the bus analyzer, and
also propagate the physical slot/channel mapping.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 74 insertions, 15 deletions

diff --git a/arch/sh/drivers/pci/pcie-sh7786.c b/arch/sh/drivers/pci/pcie-sh7786.c
index 95d095f26d66..ae91a2dd9183 100644
--- a/arch/sh/drivers/pci/pcie-sh7786.c
+++ b/arch/sh/drivers/pci/pcie-sh7786.c
@@ -204,7 +204,9 @@ static int pcie_init(struct sh7786_pcie_port *port)
 {
 	struct pci_channel *chan = port->hose;
 	unsigned int data;
-	int ret;
+	phys_addr_t memphys;
+	size_t memsize;
+	int ret, i;
 
 	/* Begin initialization */
 	pci_write_reg(chan, 0, SH4A_PCIETCTLR);
@@ -227,15 +229,24 @@ static int pcie_init(struct sh7786_pcie_port *port)
 	data |= PCI_CAP_ID_EXP;
 	pci_write_reg(chan, data, SH4A_PCIEEXPCAP0);
 
-	/* Enable x4 link width and extended sync. */
+	/* Enable data link layer active state reporting */
+	pci_write_reg(chan, PCI_EXP_LNKCAP_DLLLARC, SH4A_PCIEEXPCAP3);
+
+	/* Enable extended sync and ASPM L0s support */
 	data = pci_read_reg(chan, SH4A_PCIEEXPCAP4);
-	data &= ~(PCI_EXP_LNKSTA_NLW << 16);
-	data |= (1 << 22) | PCI_EXP_LNKCTL_ES;
+	data &= ~PCI_EXP_LNKCTL_ASPMC;
+	data |= PCI_EXP_LNKCTL_ES | 1;
 	pci_write_reg(chan, data, SH4A_PCIEEXPCAP4);
 
+	/* Write out the physical slot number */
+	data = pci_read_reg(chan, SH4A_PCIEEXPCAP5);
+	data &= ~PCI_EXP_SLTCAP_PSN;
+	data |= (port->index + 1) << 19;
+	pci_write_reg(chan, data, SH4A_PCIEEXPCAP5);
+
 	/* Set the completion timer timeout to the maximum 32ms. */
 	data = pci_read_reg(chan, SH4A_PCIETLCTLR);
-	data &= ~0xffff;
+	data &= ~0x3f00;
 	data |= 0x32 << 8;
 	pci_write_reg(chan, data, SH4A_PCIETLCTLR);
 
@@ -248,6 +259,33 @@ static int pcie_init(struct sh7786_pcie_port *port)
 	data |= (0xff << 16);
 	pci_write_reg(chan, data, SH4A_PCIEMACCTLR);
 
+	memphys = __pa(memory_start);
+	memsize = roundup_pow_of_two(memory_end - memory_start);
+
+	/*
+	 * If there's more than 512MB of memory, we need to roll over to
+	 * LAR1/LAMR1.
+	 */
+	if (memsize > SZ_512M) {
+		__raw_writel(memphys + SZ_512M, chan->reg_base + SH4A_PCIELAR1);
+		__raw_writel(((memsize - SZ_512M) - SZ_256) | 1,
+			     chan->reg_base + SH4A_PCIELAMR1);
+		memsize = SZ_512M;
+	} else {
+		/*
+		 * Otherwise just zero it out and disable it.
+		 */
+		__raw_writel(0, chan->reg_base + SH4A_PCIELAR1);
+		__raw_writel(0, chan->reg_base + SH4A_PCIELAMR1);
+	}
+
+	/*
+	 * LAR0/LAMR0 covers up to the first 512MB, which is enough to
+	 * cover all of lowmem on most platforms.
+	 */
+	__raw_writel(memphys, chan->reg_base + SH4A_PCIELAR0);
+	__raw_writel((memsize - SZ_256) | 1, chan->reg_base + SH4A_PCIELAMR0);
+
 	/* Finish initialization */
 	data = pci_read_reg(chan, SH4A_PCIETCTLR);
 	data |= 0x1;
@@ -267,10 +305,14 @@ static int pcie_init(struct sh7786_pcie_port *port)
 	if (unlikely(ret != 0))
 		return -ENODEV;
 
-	pci_write_reg(chan, 0x00100007, SH4A_PCIEPCICONF1);
+	data = pci_read_reg(chan, SH4A_PCIEPCICONF1);
+	data &= ~(PCI_STATUS_DEVSEL_MASK << 16);
+	data |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
+		(PCI_STATUS_CAP_LIST | PCI_STATUS_DEVSEL_FAST) << 16;
+	pci_write_reg(chan, data, SH4A_PCIEPCICONF1);
+
 	pci_write_reg(chan, 0x80888000, SH4A_PCIETXVC0DCTLR);
 	pci_write_reg(chan, 0x00222000, SH4A_PCIERXVC0DCTLR);
-	pci_write_reg(chan, 0x000050A0, SH4A_PCIEEXPCAP2);
 
 	wmb();
 
@@ -278,15 +320,32 @@ static int pcie_init(struct sh7786_pcie_port *port)
 	printk(KERN_NOTICE "PCI: PCIe#%d link width %d\n",
 	       port->index, (data >> 20) & 0x3f);
 
-	pci_write_reg(chan, 0x007c0000, SH4A_PCIEPAMR0);
-	pci_write_reg(chan, 0x00000000, SH4A_PCIEPARH0);
-	pci_write_reg(chan, 0x00000000, SH4A_PCIEPARL0);
-	pci_write_reg(chan, 0x80000100, SH4A_PCIEPTCTLR0);
 
-	pci_write_reg(chan, 0x03fc0000, SH4A_PCIEPAMR2);
-	pci_write_reg(chan, 0x00000000, SH4A_PCIEPARH2);
-	pci_write_reg(chan, 0x00000000, SH4A_PCIEPARL2);
-	pci_write_reg(chan, 0x80000000, SH4A_PCIEPTCTLR2);
+	for (i = 0; i < chan->nr_resources; i++) {
+		struct resource *res = chan->resources + i;
+		resource_size_t size;
+		u32 enable_mask;
+
+		pci_write_reg(chan, 0x00000000, SH4A_PCIEPTCTLR(i));
+
+		size = resource_size(res);
+
+		/*
+		 * The PAMR mask is calculated in units of 256kB, which
+		 * keeps things pretty simple.
+		 */
+		__raw_writel(((roundup_pow_of_two(size) / SZ_256K) - 1) << 18,
+			     chan->reg_base + SH4A_PCIEPAMR(i));
+
+		pci_write_reg(chan, 0x00000000, SH4A_PCIEPARH(i));
+		pci_write_reg(chan, 0x00000000, SH4A_PCIEPARL(i));
+
+		enable_mask = MASK_PARE;
+		if (res->flags & IORESOURCE_IO)
+			enable_mask |= MASK_SPC;
+
+		pci_write_reg(chan, enable_mask, SH4A_PCIEPTCTLR(i));
+	}
 
 	return 0;
 }