Shares in chipmaker ARM Holdings have been boosted after Morgan Stanley upgraded the stock to 'overweight' from 'equalweight' and raised its share price target to 1,180p from 980p.The bank said that concerns around a slowdown of the smartphone market have created a buying opportunity for ARM, noting that the stock is barely up year-to-date, at the bottom of its five-year price-to-earnings range.Investec has lifted its rating for Lloyds 'sell' to 'hold,' and upped its price target from 84p to 86p.Analyst Ian Gordon said a recent price correction meant the bank was close to fair value, and he was encouraged by the rapid sell down of the UK government's stake.JP Morgan Cazenove downgraded Rolls-Royce and slashed its target price after the engine maker's profit warning on Monday, foreseeing three or four years of uninspiring sales and low returns.The UK broking arm of the US bank cut its rating to 'underweight' from 'netural' and reduced its price target to 640p from the previous 900p on what it said was the most expensive stock in the aerospace and defence space "by some measure".Land Securities rose to the top of the FTSE 100 after UBS upgraded the stock to 'buy' from 'neutral' and raised the price target to 1,425p from 1,300p.Analysts at the bank noted how the stock has been trading very tightly around net asset value for the past few years, but in recent months has de-rated and currently stands at a 7% discount to spot NAV and 14% discount to UBS' March 2016 forecast of 1,426p.